JRC TECHNICAL REPORTS

Evaluation of the
Field Comparison Exercise
for PM10 and PM2.5
Ispra, 18 January to 14 March 2018

European Commission Harmonisation Programme for Air Quality Measurements

This publication is a Technical report by the Joint Research Centre (JRC), the European Commission’s science and knowledge service. It aims to provide evidence-based scientific support to the European policymaking process. The scientific output expressed does not imply a policy position of the European Commission. Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use that might be made of this publication.

Contact information

Name: Friedrich LAGLER

Address: European Commission, Joint Research Centre (JRC), Ispra, Italy

Email: friedrich.lagler@ec.europa.eu

Tel.: +39 0332 789990

EU Science Hub

https://ec.europa.eu/jrc

JRC Mission

As the science and knowledge service of the European Commission, the Joint Research Centre’s mission is to support EU policies with independent evidence throughout the whole policy cycle.

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JRC118170

EUR 29939 EN

PDF

ISBN 978-92-76-10168-0

ISSN 1831-9424

doi:10.2760/32013

EPUB

ISBN 978-92-76-14164-8

ISSN 1831-9424

doi:10.2760/9159

Luxembourg: Publications Office of the European Union, 2019

© European Union, 2019

The reuse policy of the European Commission is implemented by Commission Decision 2011/833/EU of 12 December 2011 on the reuse of Commission documents (OJ L 330, 14.12.2011, p. 39). Reuse is authorised, provided the source of the document is acknowledged and its original meaning or message is not distorted. The European Commission shall not be liable for any consequence stemming from the reuse. For any use or reproduction of photos or other material that is not owned by the EU, permission must be sought directly from the copyright holders.

All content © European Union, 2019, except page 17, figure 1, 2016, Google earth

How to cite this report: Lagler F., Barbiere M., Borowiak A., Putaud J.P. Evaluation of the field comparison exercise for PM10 and PM2.5 Ispra, 18 January to 14 March 2018 - European Commission Harmonisation Programme for Air Quality Measurements, EUR 29939 EN, Publications Office of the European Union, Luxembourg, 2019, ISBN 978-92-76-10168-0, doi:10.2760/32013, JRC118170

Acknowledgements

In collaboration with:

B. Stacey

T. Zang, C. Iwczenko, S. Leinert

S. Bernberg, C. Nordstroem

J. Matos, S. Casimiro, F. Guerreiro

G. Stefess, J. Vonk

V. Dezsi, G. Polay, G. Kovacs

A. Pindel, T. Fraczkowski

I. Beslic, S. Davila

A. Hakansson, T. Ondrej

T. Gaizutis, J. Molis

J. Knezevic, J. Lecic

F. Fusenig, C. Magar

D. Muck, P. Fays

P. Bruyndonckx, I. Naveau, K. Bellekens, M. De Gier

R. Aujay-Plouzeau, C. Ferret

I. Kranjc, P. Pavli, B. Ropotar

K. Pletscher, J.P. Graewingholt

S. Rychlik, J. Silhavy

T. Kernecker, A. Kreiner

J. Walden, M. Vestenius

D. Centioli, F. Cadoni, C. Ravaioli

M. Craciun, R. Franco Peteira

F. Dauge, L. Marsteen

L. Delaney, C. Ruane, K. Delaney, M. O’Dwyer

T. Truuts, A. Viidik, A. Ebber, V. Kotsura

M. Froehlich, A. Wolf

A special thanks to the following JRC colleagues who contributed with substantial logistical and technical efforts to the successful completion of the PM ILC:

E. Battistoni, A. Dell’Acqua, V. Pedroni

List of figures

Figure 1: Measurement platform

Figure 2: Sampler positions (with day of installation in different colours)

Figure 3: Samplers and measurement site

Figure 4: Ambient temperature (1h-avg) at measurement site

Figure 5: Ambient relative humidity (1h-avg) at measurement site

Figure 6: Ambient pressure (1h-avg) at measurement site

Figure 7: Precipitation (accumulation in 1h) at measurement site

Figure 8: Wind-speed (1h-avg) at measurement site

Figure 9: Wind-direction (1h-avg) at measurement site

Figure 10: Assigned Values for PM10 and PM2.5 over the measurement period

Figure 11: Histogram of the Assigned Values for PM10

Figure 12: Histogram of the Assigned Values for PM2.5

Figure 13: Ratio of PM2.5/PM10 Assigned Values

Figure 14: PM10 data of all participants using the gravimetric method

Figure 15: PM2.5 data of all participants using the gravimetric method

Figure 16: z’-scores for PM10 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown. Entries >4.5 (also dark brown) are labelled with their value (e.g. 4.6).

Figure 17: z’-scores for PM2.5 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Figure 18: En-scores for PM10 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Figure 19: En-scores for PM2.5 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Figure 20: Expanded uncertainties of all participants’ PM10 data and the Assigned Value (in solid black), 2*σpt (in dashed black)

Figure 21: Expanded uncertainties of all participants’ PM2.5 data and the Assigned Value (in solid black), 2*σpt (in dashed black)

Figure 22: Expanded uncertainties vs. concentration of all participants’ PM10 data

Figure 23: Expanded uncertainties vs. concentration of all participants’ PM2.5 data

Figure 24: PM10 method reproducibility versus concentration

Figure 25: PM2.5 method reproducibility versus concentration

Figure 26: Chart of z’-score evaluation for PM10 related to Lab. A

Figure 27: Chart of z’-score evaluation for PM10 related to Lab. B

Figure 28: Chart of z’-score evaluation for PM10 related to Lab. C

Figure 29: Chart of z’-score evaluation for PM10 related to Lab. E

Figure 30: Chart of z’-score evaluation for PM10 related to Lab. F

Figure 31: Chart of z’-score evaluation for PM10 related to Lab. G

Figure 32: Chart of z’-score evaluation for PM10 related to Lab. H

Figure 33: Chart of z’-score evaluation for PM10 related to Lab. I

Figure 34: Chart of z’-score evaluation for PM10 related to Lab. J

Figure 35: Chart of z’-score evaluation for PM10 related to Lab. K

Figure 36: Chart of z’-score evaluation for PM10 related to Lab. L

Figure 37: Chart of z’-score evaluation for PM10 related to Lab. M

Figure 38: Chart of z’-score evaluation for PM10 related to Lab. N

Figure 39: Chart of z’-score evaluation for PM10 related to Lab. O

Figure 40: Chart of z’-score evaluation for PM10 related to Lab. P

Figure 41: Chart of z’-score evaluation for PM10 related to Lab. Q

Figure 42: Chart of z’-score evaluation for PM10 related to Lab. R

Figure 43: Chart of z’-score evaluation for PM10 related to Lab. S

Figure 44: Chart of z’-score evaluation for PM10 related to Lab. T

Figure 45: Chart of z’-score evaluation for PM10 related to Lab. U

Figure 46: Chart of z’-score evaluation for PM10 related to Lab. V

Figure 47: Chart of z’-score evaluation for PM10 related to Lab. W

Figure 48: Chart of z’-score evaluation for PM10 related to Lab. X

Figure 49: Chart of z’-score evaluation for PM10 related to Lab. Y

Figure 50: Chart of z’-score evaluation for PM10 related to Lab. Z

Figure 51: Chart of z’-score evaluation for PM10 related to Lab. AB

Figure 52: Chart of z’-score evaluation for PM10 related to Lab. AC

Figure 53: Chart of z’-score evaluation for PM10 related to Lab. AD

Figure 54: Chart of z’-score evaluation for PM2.5 related to Lab. A

Figure 55: Chart of z’-score evaluation for PM2.5 related to Lab. B

Figure 56: Chart of z’-score evaluation for PM2.5 related to Lab. C

Figure 57: Chart of z’-score evaluation for PM2.5 related to Lab. E

Figure 58: Chart of z’-score evaluation for PM2.5 related to Lab. F

Figure 59: Chart of z’-score evaluation for PM2.5 related to Lab. G

Figure 60: Chart of z’-score evaluation for PM2.5 related to Lab. H

Figure 61: Chart of z’-score evaluation for PM2.5 related to Lab. I

Figure 62: Chart of z’-score evaluation for PM2.5 related to Lab. K

Figure 63: Chart of z’-score evaluation for PM2.5 related to Lab. L

Figure 64: Chart of z’-score evaluation for PM2.5 related to Lab. M

Figure 65: Chart of z’-score evaluation for PM2.5 related to Lab. N

Figure 66: Chart of z’-score evaluation for PM2.5 related to Lab. O

Figure 67: Chart of z’-score evaluation for PM2.5 related to Lab. P

Figure 68: Chart of z’-score evaluation for PM2.5 related to Lab. Q

Figure 69: Chart of z’-score evaluation for PM2.5 related to Lab. S

Figure 70: Chart of z’-score evaluation for PM2.5 related to Lab. T

Figure 71: Chart of z’-score evaluation for PM2.5 related to Lab. V

Figure 72: Chart of z’-score evaluation for PM2.5 related to Lab. W

Figure 73: Chart of z’-score evaluation for PM2.5 related to Lab. X

Figure 74: Chart of z’-score evaluation for PM2.5 related to Lab. Y

Figure 75: Chart of z’-score evaluation for PM2.5 related to Lab. Z

Figure 76: Chart of z’-score evaluation for PM2.5 related to Lab. AD

Figure 77: Chart of Bias evaluation for PM10 related to Lab. A

Figure 78: Chart of Bias evaluation for PM10 related to Lab. B

Figure 79: Chart of Bias evaluation for PM10 related to Lab. C

Figure 80: Chart of Bias evaluation for PM10 related to Lab. E

Figure 81: Chart of Bias evaluation for PM10 related to Lab. F

Figure 82: Chart of Bias evaluation for PM10 related to Lab. G

Figure 83: Chart of Bias evaluation for PM10 related to Lab. H

Figure 84: Chart of Bias evaluation for PM10 related to Lab. I

Figure 85: Chart of Bias evaluation for PM10 related to Lab. J

Figure 86: Chart of Bias evaluation for PM10 related to Lab. K

Figure 87: Chart of Bias evaluation for PM10 related to Lab. L

Figure 88: Chart of Bias evaluation for PM10 related to Lab. M

Figure 89: Chart of Bias evaluation for PM10 related to Lab. N

Figure 90: Chart of Bias evaluation for PM10 related to Lab. O

Figure 91: Chart of Bias evaluation for PM10 related to Lab. P

Figure 92: Chart of Bias evaluation for PM10 related to Lab. Q

Figure 93: Chart of Bias evaluation for PM10 related to Lab. R

Figure 94: Chart of Bias evaluation for PM10 related to Lab. S

Figure 95: Chart of Bias evaluation for PM10 related to Lab. T

Figure 96: Chart of Bias evaluation for PM10 related to Lab. U

Figure 97: Chart of Bias evaluation for PM10 related to Lab. V

Figure 98: Chart of Bias evaluation for PM10 related to Lab. W

Figure 99: Chart of Bias evaluation for PM10 related to Lab. X

Figure 100: Chart of Bias evaluation for PM10 related to Lab. Y

Figure 101: Chart of Bias evaluation for PM10 related to Lab. Z

Figure 102: Chart of Bias evaluation for PM10 related to Lab. AB

Figure 103: Chart of Bias evaluation for PM10 related to Lab. AC

Figure 104: Chart of Bias evaluation for PM10 related to Lab. AD

Figure 105: Chart of Bias evaluation for PM2.5 related to Lab. A

Figure 106: Chart of Bias evaluation for PM2.5 related to Lab. B

Figure 107: Chart of Bias evaluation for PM2.5 related to Lab. C

Figure 108: Chart of Bias evaluation for PM2.5 related to Lab. E

Figure 109: Chart of Bias evaluation for PM2.5 related to Lab. F

Figure 110: Chart of Bias evaluation for PM2.5 related to Lab. G

Figure 111: Chart of Bias evaluation for PM2.5 related to Lab. H

Figure 112: Chart of Bias evaluation for PM2.5 related to Lab. I

Figure 113: Chart of Bias evaluation for PM2.5 related to Lab. K

Figure 114: Chart of Bias evaluation for PM2.5 related to Lab. L

Figure 115: Chart of Bias evaluation for PM2.5 related to Lab. M

Figure 116: Chart of Bias evaluation for PM2.5 related to Lab. N

Figure 117: Chart of Bias evaluation for PM2.5 related to Lab. O

Figure 118: Chart of Bias evaluation for PM2.5 related to Lab. P

Figure 119: Chart of Bias evaluation for PM2.5 related to Lab. Q

Figure 120: Chart of Bias evaluation for PM2.5 related to Lab. S

Figure 121: Chart of Bias evaluation for PM2.5 related to Lab. T

Figure 122: Chart of Bias evaluation for PM2.5 related to Lab. V

Figure 123: Chart of Bias evaluation for PM2.5 related to Lab. W

Figure 124: Chart of Bias evaluation for PM2.5 related to Lab. X

Figure 125: Chart of Bias evaluation for PM2.5 related to Lab. Y

Figure 126: Chart of Bias evaluation for PM2.5 related to Lab. Z

Figure 127: Chart of Bias evaluation for PM2.5 related to Lab. AD

List of tables

Table 1: Participating laboratories

Table 2: Equipment used for PM10 measurements

Table 3: Equipment used for PM2.5 measurements

Table 4: Outliers and stragglers for PM10

Table 5: Outliers and stragglers for PM2.5

Table 6: Summary z’-scores for PM10

Table 7: Summary z’-score for PM2.5

Table 8: Summary En-score for PM10

Table 9: Summary En-score for PM2.5

Table 10: Reproducibility for PM10 and PM2.5 of the field comparison exercise

Table 11: Assigned Values for PM10 and PM2.5 from 18 January to 16 February .

Table 12: Assigned Values for PM10 and PM2.5 from 17 February to 14 March

Table 13: Participants’ value PM10 lab code from A to H

Table 14: Participants’ value PM10 lab code from I to P

Table 15: Participants’ value PM10 lab code from Q to X

Table 16: Participants’ value PM10 lab code from Y to AD and σpt

Table 17: Participants’ value PM2.5 lab code from A to H

Table 18: Participants’ value PM2.5 lab code from I to P

Table 19: Participants’ value PM2.5 lab code from Q to X

Table 20: Participants’ value PM2.5 lab code from Y to AD and σpt

Abbreviations

DQO

Data Quality Objective of the European Directive 2008/50/EC

LV

Limit Value of the European Directive 2008/50/EC

AQUILA

Network of National Air Quality Reference Laboratories

WHO-CC

World Health Organisation Collaboration Centre for Air Quality

PM10

Particulate Matter in the size fraction ≤ 10 μm aerodynamic diameter

PM2.5

Particulate Matter in the size fraction ≤ 2.5 μm aerodynamic diameter

PAH

Polycyclic Aromatic Hydrocarbons

ERLAP

European Reference Laboratory for Air Pollution

HVS

High Volume Sampler

LVS

Low Volume Sampler

PTFE

Polytetrafluoroethylene

JRC

Joint Research Centre of the European Commission

EC

European Commission

ISO

International Organisation for Standardisation

Avg

Average

U

Expanded Uncertainty (k=2)

R

Reproducibility

ILC

Inter-laboratory comparison exercise

UTC

Coordinated Universal Time

CEN

European Committee for Standardisation

Abstract

The Joint Research Centre of the European Union (JRC) is conducting proficiency tests for air pollutants regulated by European Directive [1]. For National Reference Laboratories of the EU participation is obligatory with the scope to demonstrate comparability between Member States.

An inter-laboratory comparison exercise (ILC) for the determination of PM mass concentration with the reference gravimetric method (EN 12341:2014) was organised for the first time at European level in 2015 in Ispra, Italy. The second ILC of this kind took place in 2018. Such an ILC comprises the comparison between the samplers used by the various participants and includes the whole implementation of the reference method.

Samplers are therefore co-located for several days so that the number of test samples is large enough for statistical analyses. Thanks to the great interest for this type of ILC and to the commitment from the AQUILA Network members, 26 Laboratories plus the European Reference Laboratory for Air Pollution deployed their instruments at a single place in the premises of the Joint Research Centre in Ispra (Italy) during the same period of time (18 Januar – 14 March 2018). 28 samplers and one automatic analyser for PM10 and 23 samplers and one automatic analyser for PM2.5 collected ambient aerosol samples. Gravimetric analyses of the filters before and after sampling were performed by the participants in their own laboratories following their own conditioning and filter handling procedures.

The assigned daily values for PM10 and PM2.5 were calculated as the robust average of all participants. They ranged from 5.8 to 76.6 μg/m for PM10, and from 4.8 to 69.2 μg/m for PM2.5.

The scope of this inter-laboratory comparison was to assess the robustness of the measurement process and to determine the performance of the participants’ procedures. From the statistical analyses, conclusions on the performance of the method could also be drawn.

The reproducibility of the method was 11% for both PM10 and PM2.5.

After excluding blunders, for PM10, out of 1470 reported daily values, 38 (2.6%) were found to be unsatisfactory with respect to the z’-score criterion (|z’|≥3). For PM2.5, out of 1203 daily averages, only 8 (0.7%) showed an unsatisfactory result. Questionable results (3>|z’|>2) amounted 2.8% and 5.7% of all PM10 and PM2.5 data, respectively.

The En-score, which takes into account also the uncertainties reported by the participants, exceeded the critical threshold (|En|≥1) for 6.3% and 9.3% of the PM10 and PM2.5 reported data, respectively.

The overall results of the ILC show a similar performance as in 2015, which suggests that the measurement procedures have already reached a rather high level of quality.

1.   Introduction

Particulate matter (PM) is considered as the most harmful air pollutant in outdoor air for human health. To protect human health the EU agreed on limit values for PM2.5 and PM10, as well as on an exposure reduction target for PM2.5, which are described in the Air Quality Directive [1]. The correct measurement of the two particulate size fractions PM2.5 and PM10 is not only required by the Directive, but is also essential for a harmonised assessment of concentration levels, to detect the successful implementation of emission reductions and to identify changing emission patterns or sources at local, regional and global level.

The Air Quality Directive sets the legal basis for a harmonised assessment of air pollutants in Europe. The reference measurement methods for PM2.5 and PM10 are described in the European standard EN 12341:2014 [2]. Requirements on the data quality are set as minimum objectives for the uncertainty of the measurement itself, and as minimum data capture.

The accuracy of the PM measurements has to be assured and continuously controlled in line with the Air Quality Directive and requirements of international standards for accreditation. The EC’s Joint Research Centre is the responsible body organising quality assurance at EU level, in collaboration with the AQUILA Network [3]. Each Member States’ National air quality reference laboratory in charge of the quality of air pollution measurements has to participate regularly to the quality assurance programmes organised by the European Commission’s Joint Research Centre in Ispra. While for gaseous air pollutants inter-laboratory tests can be carried out in a special dynamic test gas generation facility [4] or by distribution of gas cylinders, these methods are not possible for aerosols.

Between 2006 and 2009 the JRC carried out a unique quality control programme in 18 Member States, where the JRC employed reference method measured in parallel to national reference sampling instruments and a monitoring station in the Member State. Detailed results of the campaign are described in a EUR report [5].

In 2015 the JRC, in collaboration with the AQUILA Network of National Air Quality Reference Laboratories, organised for the first time an outdoor inter-laboratory comparison exercise (ILC) in Ispra, Italy, for PM10 and PM2.5 measurements. A platform was identified inside the premises of the Joint Research Centre, which offered enough space for a larger number of sampling instruments, without being influenced by near-by local emission sources, which could impact on the homogeneity of the sampling platform. Detailed results are described in a EUR report [6].

In 2018 the JRC, in collaboration with the AQUILA Network of National Air Quality Reference Laboratories, organised a similar campaign as in 2015. In addition to the gravimetric method, automatic samplers could be used. The same campaign served as well as an ILC for PAHs and heavy metals, the results of which will be published in separate documents.

The PM ILC was announced to the AQUILA network and the WHO-CC representatives at the 26th AQUILA meeting (November 2016), and more detailed at the 27th AQUILA meeting in September 2017, where logistical and technical requirements and boundaries were discussed. The platform was presented to the AQUILA community at the occasion of previous AQUILA meetings. Static tests of the platform confirmed its suitability and subsequently electrical lines were installed to allow for proper and stable electricity supply to all instruments.

In order to catch a period with both low and high PM pollution levels, it was decided to start sampling in January 2018. During a period of 8 weeks, up to 56 filters per PM size fraction could be collected by the participants.

2.   Organisation of the field comparison

The comparison took place on the premises of the EC’s Joint Research Centre in Ispra, Italy. Participants were requested to bring their own PM10 and PM2.5 samplers, following the recommendations from the Reference Method for Particulate Matter as described in EN12341:2014, as well as the equipment necessary to check the samplers on site. Automatic analysers were admitted, too.

The installation of the samplers took place in the period 15 – 17 January 2018, with a selected number of laboratories invited each day. Sampling started on 18 January 2018, at 0:00 a.m. UTC and ended after 8 weeks on 14 March 2018, at 12:00 p.m. Participants were requested to pass by every 2 weeks to exchange the loaded filter cartridges with unloaded filter cartridges or to provide unloaded filter cartridges which were exchanged by JRC staff. Within the first week after the end of the campaign, participants passed by to dismantle their equipment.

Data were reported by the participants via a web application. Daily values (0:00 a.m. – 12:00 p.m. UTC) and associated uncertainties were inserted by the participants together with a questionnaire regarding the used equipment and sampling details.

2.1  Participants

23 countries plus the Joint Research Centre of the European Commission were represented during the ILC. 27 laboratories participated in the comparison of PM10 and 23 in the comparison of PM2.5. The European Reference Laboratory for Air Pollution (ERLAP) participated with 2 samplers for PM10 and 2 samplers for PM2.5, ISSeP (BE) participated with an additional PM10 sampler, hence bringing the total number of datasets for PM10 to 29 and for PM2.5 to 24. Most of the participants are accredited according to ISO 17025:2005 [7]. Details of each laboratory are given in Table 1.

Table 1: Participating laboratories

COUNTRY

LABORATORY

ACRONYM

PM10

PM2.5

CODE

GERMANY

Landesamt fűr Natur, Umwelt und Verbraucherschute

LANUV

X

X

A

PORTUGAL

Agência Portuguesa do Ambiente

APA

X

X

B

DENMARK

National Environmental Research Institute

DCE

X

X

C

UNITED KINGDOM

Ricardo Energy and Environment - AEA

RICARDO-AEA

X

X

D

AUSTRIA

Environment Agency Austria

EAA

X

X

E

POLAND

Chief Inspectorate of Environmental Protection

GIOS

X

X

F

EUROPEAN COMMISSION

European Reference Laboratory for Air Pollution

ERLAP

X

X

G

NETHERLANDS

National Institute for Public Health and the Environment

RIVM

X

X

H

HUNGARY

Hungarian Meteorological Service

HMS

X

X

1

ESTONIA

Estonian Environmental Research Centre

EERC

X

J

IRELAND

Environmental Protection Agency

EPA

X

X

K

CROATIA

Institute for Medical Research and Occupational Health

IMI

X

X

L

LITHUANIA

Environmental Protection Agency

AAA

X

X

M

SWEDEN

Department of Environmental Science and Analytical Chemistry

ACES

X

X

N

LUXEMBOURG

Service Surveillance et Controle de la Qualite de Air

AEV

X

X

O

SERBIA

Serbian Environmental Protection Agency

SEPA

X

X

P

BELGIUM

Institut Scientifique de Service Public

ISSeP

X

X

Q

SLOVENIA

Environmental Agency of the Republic of Slovenia

SEA

X

R

BELGIUM

Flemish Environmental Agency

VMM

X

X

S

FRANCE

Institut National de I’Environnement Industriel et des Risques

INERIS

X

X

T

CZECH REPUBLIC

Czech Hydrometeorological Institute

CHMI

X

U

GERMANY

TÜV Rheinland Energy GmbH

TUV

X

X

V

ITALY

Istituto Superiore per la Protezione e Ricerca Ambientale

ISPRA

X

X

w

FINLAND

Finnish Metrological Institute

FMI

X

X

X

SPAIN

Instituto de Salud Carlos III

IS C I 11

X

X

Y

AUSTRIA

Upper Austria Regional Government

OOE

X

X

z

NORWAY

Norwegian Institute for Air Research

NILU

X

AB

BELGIUM

Institut Scientifique de Service Public

ISSeP II

X

AC

EUROPEAN COMMISSION

European Reference Laboratory for Air Pollution

ERLAP II

X

X

AD

2.2  Equipment

Each participant provided information regarding the type of filter material, the type of sampler and if a cooling system for loaded filters was used.

In the PM10 comparison, 5 High Volume Samplers (HVS), 23 Low Volume Samplers (LVS) and 1 automatic analyser were used, whereas in the PM2.5 comparison 2 HVS, 21 LVS and 1 automatic analyser were used.

Regarding the filter material, Quartz filters were used by 17, Glass filters by 5, Emfab by 4 and PTFE by 2 laboratories for PM10 sampling. For PM2.5, Quartz filters were used by 13, Glass filters by 5, Emfab by 4, and PTFE by 1 laboratories.

Cooling systems for loaded filters were used by 14 laboratories for both PM10 and PM2.5, 14 laboratories for PM10 and 9 for PM2.5 worked without. Table 2 and 3, separated into PM10 and PM2.5, list in detail the equipment used by each laboratory.

Table 2: Equipment used for PM10 measurements

PM10

ACRONYM

INSTRUMENT

FLOWRATE

FILTERMATERIAL

COOLING SYSTEM

LANUV

Digitel DHA-80 Touchscreen

30m³/h

Quartz Fibre Filter QF 150 mm, Munktell Ahlstrom

No

APA

Digitel DPA14 gravimetric sampler

2.3 m³/h

Glass fibre

Yes

DCE

Leckel SEQ 47/50-CD

2.3 m³/h

Whatman Grade QM-A Quartz Filter, circle, 47 mm

Yes

RICAROO-AEA

Palas Fidas 200S

4.8 l/min

EAA

Digitel LVS 14

2.3 m³/h

MUNKTELL Micro-glassfibre filter Grade: MG 227/1/60

No

GIOS

Leek el SEQ 47/50

2.3 m³/h

Whatman QMA 47mm 1851-047

Yes

ERLAP

Leek el SEQ 47/50

2.3 m³/h

Quartz fibre filters Pallflex 2500 OAT

No

RIVM

Sven Leckel SEQ 47/50

2.3 m³/h

Whatman QM-A Quartz Microfibre 47 mm

No

HMS

Digitel DHA 80

30 m³/h

Frisenette quart: fibre filter QF15D

No

EERC

Digitel DHA 80

30 m³/h

Quartz Microfibre Filters QMA 150 mm; CAT. No. 1851-150,-Whatman

No

EPA

Leek el SEQ 47/50

2.3 m³/h

Glass Microfibre

No

IMI

Leckel SEQ 47/50-CD

2.3 m³/h

Whatman QMA, quart:

Yes

AAA

Leek el SEQ 47/50

2.3 m³/h

Quartz fibre filters (Type AQFA AC4700)

Yes

ACES

Derenda PNS 18T DM-3.1

2.3 m³/h

Emfab

Yes

AEV

Leek el SEQ 47/50

2.3 m³/h

MK360 Munktell Quarzfaser Filter 47mm

No

SEPA

Leckel SEQ 47/50

2.3 m³/h

Whatman QMA

No

ISSeP

Derenda PNS16-S.1

2.3 m³/h

Pal If lex Emfab

Yes

SEA

Digitel DHA80

30 m³/h

Filters PALL, 2500QAT-UP, 150mm, XQ250ETDS015D, 25/1

No

VMM

Derenda PNS 1ST

2.3 m³/h

Pall Tissuquart: 25DDqat-up

No

INERIS

Leckel SEQ 47/50-CD

2.3 m³/h

Pallflex© Emfab™ Filters : Borosilicate microfibres reinforced with woven glass cloth and bonded with PTFE. Diameter 47 mm

Yes

CHMI

Leckel SEQ 47/50-CD

2.3 m³/h

Whatman, type GF/C, cat.no. 1822-047, glass fibre, 1.2 μm, binder free

Yes

TUV

Leek el SEQ 47/50

2.3 m³/h

Emfab

No

ISPRA

TCR Tecora Skypost HV

2.3 m³/h

Quartz fibre Munktell Ahlstrom MK360 47 mm lot n. 2956437

Yes

FMI

Leckel SEQ 47/50

2.3 m³/h

polytetrafluoroethylene (PTFE) filters, Millipore Fluoropore FSLW047 # 3 μm

Yes

ISCIII

IND DERENDA LVS

2.3 m³/h

QMA 47mm diameter

Yes

OOE

Digitel HVS DHABD

30 m³/h

Munktell Glass-Microfibre Discs 1336/2

No

NILU

Leckel SEQ47/50

2.3 m³/h

Teflon, Pall corp., Zefluor, 2 micron

Yes

ISSeP II

Derenda PNS18T6.1-DM, inlet mesh removed

2.3 m³/h

Quartz filter (47mm): Whatman QM-A

Yes

ERLAP II

Leckel SEQ 47/50

2.3 m³/h

Quartz fibre filters Pallflex 2500 OAT

No

Table 3: Equipment used for PM2.5 measurements

PM2.5

ACRONYM

INSTRUMENT

FLOWRATE

FILTER MATERIAL

COOLING SYSTEM

LANUV

Leckel SEQ47/50

2.3 m³/h

glass fibre filter

No

APA

Digitel DPA14 gravimetric sampler

2.3 m³/h

Glass fibre

Yes

DCE

Leckel SEQ 47/50-CD

2.3 m³/h

Whatman Grade QM-A Quart: Filter, circle, 47 mm

Yes

RICARDO-AEA

Palas Fidas ZOOS

4.8 l/min

EAA

Digitel LVS 14

2.3 m³/h

MUNKTELL Micro-glassfibre filter Grade: MG 227/1/60

No

GIOS

Leckel SEQ 47/50

2.3 m³/h

Whatman QMA 47mm 1851-047

Yes

ERLAP

Leckel SEQ 47/50

2.3 m³/h

Quartz fibre filters Pallflex 2500 QAT

Yes

RIVM

Derenda PNS16T

2.3 m³/h

Whatman QM-A Quartz Microfibre 47 mm

Yes

HMS

Digitel DHA 8O

30 m³/h

Frisenette quart: fibre filter QF150

No

EPA

Leckel SEQ 47/50

2.3 m³/h

Glass Microfibre

No

IMI

Leckel SEQ 47/50-CD

2.3 m³/h

Whatman QMA, quartz

Yes

AAA

Leckel SEQ 47/50

2.3 m³/h

Quartz fibre filters (Type AQFA A04700)

Yes

ACES

Derenda PNS 1ST DM-3.1

2.3 m³/h

Emfab

Yes

AEV

Leckel SEQ 47/50

2.3 m³/h

MK360 Munktell Quarzfaser Filter 47mm

No

SEPA

Leckel SEQ 47/50

2.3 m³/h

Whatman QMA

No

ISSeP

Derenda PNS 16-6.1

2.3 m³/h

Pallflex Emfab

Yes

VMM

Derenda PNS 18T

2.3m³/h

Pall Tissuquartz 2500qat-up

No

INERIS

Leckel SEQ 47/50-CD

2.3 m³/h

Pallflex© Emfab™ Filters : Borosilicate microfibres reinforced with woven glass cloth and bonded with PTFE. Diameter 47 mm

Yes

TUV

Leckel SEQ 47/50

2.3 m³/h

Emfab

No

ISPRA

TCR Tecora Skypost HV

2.3m³/h

Quart: fibre Munktell Ahlstrom MK360 47mm lot n. 2356437

Yes

FMI

Leckel SEQ 47/50

2.3m³/h

polytetrafluoroethylene (PTFE) filters, Millipore Fluoropore FSLW047 # 3 μm

Yes

ISCIII

IND DERENDA LVS

2.3m³/h

QMA47mm diameter

Yes

00E

Digitel DHA 80

30 m³/h

Munktell Glass-Microfibre Discs 1336/2

No

ERLAP II

Leckel SEQ 47/50

2.3m³/h

Quartz fibre filters Pallflex 2500 QAT

Yes

2.3  Measurement site

2.3.1   Location

As measurement site, the roof of a water reservoir (building 35a) on the premises of the Joint Research Centre of the European Commission in Ispra, Italy, has been chosen. The area is fenced with restricted access.

The site is situated in the pre-alpine area in northern Italy. Both high and low concentrations of particulate matter could be expected, as the site is on one hand influenced by the highly polluted Po-valley, on the other hand exposed to situations with strong foehn winds from the Alps transporting clean air.

The roof of building 35a is around 1-2 m above ground and free of obstacles in the surroundings. Roads near the platform are frequented by JRC personnel only, mainly in the morning, lunchtime and at the end of a working day. Figure 1 shows the area around the measurement site.

Figure 1: Measurement platform

2.3.2   Positions of samplers

Power supply and pathways for accessibility were installed by the JRC infrastructure service. All instruments for PM measurements were positioned in the south-eastern area, instruments for the PAH sampling were positioned in the northern area of the platform. The following drawing illustrates the position of each single sampler. Each box represents a sampler, identified by the Lab-code (see legend in Fig. 2), a suffix “a” for PM10, “b” for PM2.5 and “c”- “l” for an additional instrument (which could be for PAH, an automatic analyser or an additional PM sampler).

Figure 2: Sampler positions (with day of installation in different colours)

All instruments were labelled with details of the laboratory and checked daily by JRC staff according to a predefined check list. In case of malfunction, the concerned laboratory was informed and whenever possible, the problem was solved by JRC staff. A total of 17 repair works were registered over the entire sampling period. Figure 3 shows a picture of the measurement site with the samplers installed.

Figure 3: Samplers and measurement site

2.3.3   Homogeneity

The homogeneity of the measurement site was evaluated and successfully demonstrated on a day-by-day basis for the campaign in 2015 [6]. The same approach, a visual check of over- or underestimating the PM concentration with respect to the Assigned Value depending on the sampler-position on the measurement site, was performed on 9 selected days (covering the measurement period and the encountered measurement range) at the end of this campaign. No evidence of inhomogeneity could be found.

Furthermore, the between–sampler uncertainties (ubs), which in fact combine other sources of uncertainies, too, for the PM10 and PM2.5 samplers of ERLAP, positioned opposite each other on the measurement site, were calculated. The ubs of 0.9 μg/m³ for PM10 and 0.8 μg/m³ for PM2.5, calculated over the whole measurement period, underpin the homogenous distribution of PM across the measurement site.

Homeogeneity contributes to the standard uncertainty of the Assigned Value as described later in Chapter 3.2.

2.3.4   Meteorological conditions

Meteorological conditions were measured at the EMEP site on the premises of the JRC and are reported as hourly averages in Figures 4 to 9.

Temperature ranged from -9.9 °C (28 February) to 16.5 °C (14 March), ambient pressure from 967 mbar (6 March) to 1010 mbar (28 January).

Lowest PM concentrations were measured during periods characterised by low relative humidity and higher wind speed (max. 6.6 m/s on 21 January), which are characteristic for foehn events.

Days with notable precipitation were 25 – 27 January and 10 – 11 March.

Figure 4: Ambient temperature (1h-avg) at measurement site

Figure 5: Ambient relative humidity (1h-avg) at measurement site

Figure 6: Ambient pressure (1h-avg) at measurement site

Figure 7: Precipitation (accumulation in 1h) at measurement site

Figure 8: Wind-speed (1h-avg) at measurement site

Figure 9: Wind-direction (1h-avg) at measurement site

3.   The Assigned Value

3.1  Selection and calculation of the Assigned Value

As Assigned Value xpt, the Robust Average x* (Consensus Value from all participant results) was taken according to ISO 13528:2015 [8].

The Robust Average x* and the Robust Standard Deviation s* were calculated according to ISO 13528:2015 (part C.3.1) as follows:

Calculation of initial values for x* and s*:

p items of data sorted into increasing order by: x{1}, x{2},…, x{p}

Note: p = Number of participants

x*=median of xi(i=1,2,…,p)s*=1.483 median of |xi-x*| with (i=1,2,…,p)

Update the values of x* and s* as follows:

Equation 1

δ=1.5s*

For each xi (i=1,2,…,p), calculate:

Equation 2

xi*=x*-δwhenxi<x*-δ x*+δwhenxi<x*+δxiotherwise

Calculate the new values of x*and s* from:

Equation 3

x*=∑i=1pxi*/p

Equation 4

s*=1.134∑i=1p(xi*-x*)2/(p-1)

The robust estimates x* and s* were derived by iterative calculations, updating the values of x* and s* several times using the modified data in equations 1 to 4, until the process converged. Convergence was assumed when there was no change from one iteration to the next in the third significant figure of the Robust Mean and the Robust Standard Deviation.

3.2  Calculation of the uncertainty of the Assigned Value

When the Assigned Value is derived as a robust average, ISO 13528:2015 recommends to estimate the standard uncertainty of the Assigned Value u’(xpt) according to equation 5:

Equation 5

u′(xpt)=1.25*s*p

It further proposes to include in the uncertainty budget of the Assigned Value the contribution due to homogeneity. As an estimate for homogeneity, the maximum allowable between- sampler uncertainty of 2 μg/m³ as given in EN12341(2014) is used. To confirm its validity, the between-sampler uncertainties of the ERLAP PM10 and PM2.5 samplers (see pt. 2.3.3) need to be lower.

Its contribution to the standard uncertainty of the Assigned Value is calculated according to equation 6:

Equation 6

ubs=23

Hence, the combined standard uncertainty of the Assigned Value u(xpt) is calculated according to equation 7:

Equation 7

u(xpt)u′(xpt)2+ubs2

The Expanded Uncertainty of the Assigned Value U(xpt) is calculated according to equation 8:

Equation 8

u(xpt)=2u(xpt)

4.   Concentration range of the Assigned Value

The concentration range of the Assigned Value varied from 5.8 to 76.6 μg/m³ for PM10 and from 4.8 to 69.2 μg/m³ for PM2.5. Assigned Values and uncertainties are listed in Annex A. Figure 10 shows the daily Assigned Value for PM10 and PM2.5 over the measurement period.

Figure 10: Assigned Values for PM10 and PM2.5 over the measurement period

More than 50% of the Assigned Values for PM10 and PM2.5 are in a range <40 μg/m³. Figures 11 and 12 show histograms with bins of 10 μg/m³. PM10’s frequency distribution presents one mode between 20 and 30 μg/m³, while most of PM2.5’s data fall in the range from 10 to 40 μg/m³.

Figure 11: Histogram of the Assigned Values for PM10

Figure 12: Histogram of the Assigned Values for PM2.5

The percentage of PM2.5 on PM10 from the Assigned Values is almost 92%, as estimated from the slope of the regression in Figure 13.

Figure 13: Ratio of PM2.5/PM10 Assigned Values

5.  Evaluation of the field comparison exercise

Data capture for PM10 was 93.9%, for PM2.5 similar with 93.4%.

Apart from the gravimetric method the NRLs was offered the possibility to participate in the PM ILC with automatic instruments, too. After the first announcement three NRLs declared their intention, but in the end only one NRL reported data to the ILC with an automatic instrument, based on an optical measurement technique. The results of this automatic analyser were not taken into consideration in the evaluation of the PM ILC, as the main objective of the PM ILC is to compare the reference method according to EN 12341 (2014) for PM measurement.

To evaluate the participants’ measurement proficiency, the methodology described in ISO 13528:2015 was applied. As described in chapter 3, the Robust Average x* was taken as Assigned Value xpt with its associated uncertainty u(xpt), details are listed in Annex A.

As standard deviation for proficiency assessment σpt the combined uncertainty of the method was taken, detailed values for σpt are listed in Annex B.

Note: Both σpt and u(xpt) are calculated differently from those used in the 2015 report ‘Evaluation of the Field Comparison Exercise for PM10 and PM2.5, Ispra, February 13th – April 9th, 2015’, therefore when comparing results of z’- and En-score needs to take this into account.¹

The proficiency evaluation focuses on data reflecting as much as possible every day’s work of the participating laboratories. For that reason, beforehand blunder removal (Chapter 5.1) and Grubb’s outlier tests (Chapter 5.2) were performed with the scope to remove (blunders) and detect (Grubb’s outliers) exceptional errors.

The proficiency of the participants was assessed by calculation of two performance indicators, which both test if the difference between a participants’ measured value and the Assigned Value remains within the limits of specific criteria. They were calculated individually for each participant and each sample.

The first performance indicator (z’-score) compares the difference between the participants’ measured value and the Assigned Value with the quadratic sum of the standard deviation for proficiency assessment and the standard uncertainty of the Assigned Value (Chapter 5.3).

The second performance indicator (En-score) compares the difference between a participants’ measured value and the Assigned Value with quadratic sum of the expanded uncertainties of the participants’ measurement result and the Assigned Value (Chapter 5.4).

Uncertainties of the participants’ results were compared to each other and to the one of the Assigned Value (Chapter 5.5).

To emphasize the overall uncertainty of both PM2.5 and PM10 measurements, the reproducibility of all participants was calculated both for all data and at the limit values of the European Directive 2008/50/EC, and confronted with the corresponding concentration level (Chapter 5.6).

5.1  Blunder removal

ISO 13528:2015 recommends to remove obvious blunders before any statistical data treatment.

After a visual inspection of all PM10 (see Figure 14) and PM2.5 (see Figure 15) data the following blunders were identified and removed:

Participant B: sampling days 11, 15 and 33 for PM10

The laboratories producing obvious blunders were first requested to investigate the cause of such discrepancies. They were allowed to correct their results in case of identification of exceptional errors. Subsequently, data were considered as definitive and removed before continuing with “Grubb’s outlier test”. Blunders are not included in the overall evaluation of z’- and En-scores. However, they are considered in the individual evaluations in Annex C and D.

Participant D (automatic analyser, different measurement principle than the reference method) was not considered in any evaluation, but reported data are listed in Annex B.

Figure 14: PM10 data of all participants using the gravimetric method

Figure 15: PM2.5 data of all participants using the gravimetric method

5.2  Grubb’s outlier test

The evaluation focuses on data, which are as much as possible reflecting participants performance levels and thus represents the comparability of their standard operating procedures for applying the standard EN12341:2014. For that reason a procedure for the detection of exceptional errors (error during typing, malfunction of instrumentation, etc.) was applied and a “Grubb’s test for one outlying observation” was performed according to ISO 5725, Part 2 [9].

The laboratories producing outliers were first requested to investigate the cause of such discrepancies. They were allowed to correct their results in case of identification of exceptional errors. Subsequently, data were considered as definitive and “Grubb’s test for one outlying observation” was repeated.

At this stage, data leading to the exceedance of the 1% critical value were considered outliers not due to exceptional errors. Data leading to the exceedance of the 5% critical value and not of the 1% critical value, were considered as stragglers. Outliers and stragglers were not removed in the evaluation of the z’- scores, En–scores and reproducibility. 26 outliers (1.8%) were detected for PM10 and 1 outlier (0.1%) for PM2.5.

5.2.1   PM10 Grubb’s outlier test

In Table 4 below are reported the outliers and stragglers identified during the field comparison exercise for PM10. The comments “min” or “max” indicate the side on which a critical value was exceeded.

Table 4: Outliers and stragglers for PM10

DAY

LAB

OUTLIER

STRAGGLER

2

B

max

3

B, Y

max

6

B

min

8

B

min

10

B

max

11

Y

max

13

B

min

16

B

max

21

B

max

22

B

min

24

B

min

25-31

B

min

32

B

min

34-41

B

min

45

B

max

48

B

max

50

Z

max

52

B

min

56

B

max

5.2.2   PM2.5 Grubb’s outlier test

In Table 5 below are reported the outliers and stragglers identified during the field comparison exercise for PM2.5. The comments “min” or “max” indicate the side on which a critical value was exceeded.

Table 5: Outliers and stragglers for PM2.5

DAY

LAB

OUTLIER

STRAGGLER

1

O

min

7

B

min

10

M

max

32

B

min

39

B

min

5.3  z’-scores

The z’-score statistic calculates according to ISO 13528:2015 as:

Equation 9

Zi′=xixptσpt2+u2(xpt)

Where xi is a participants value, xpt is the Assigned Value, σpt is the standard deviation for proficiency assessment and u(xpt) is the standard uncertainty of the Assigned Value.

As σpt of the ILC, the measurement uncertainty of the method (based on individual sources of uncertainty) as given in EN 12341:2014 was taken. This allows having a criterion independent from the participants’ performance and facilitates comparison to future ILCs using the same calculation given in equation 10:

Equation 10

σpt2=um2(ml-mu)2+uf2+ubs2L2

Where:

um = mass uncertainty (63 μg)

(ml-mu) = mass loaded – mass unloaded, calculated at the level of L

uf = flow uncertainty (1.7%)

ubs = between sampler variation (23)

L = actual PM concentration (daily average)

For each concentration level σpt was calculated, detailed values for each measurement day are listed in Tab. 16 and Tab. 20.

The assessment of results in the z’-score evaluation is according to the following criteria:

• |z’| ≤ 2 are considered satisfactory

• 2 < |z’| < 3 are considered questionable

• |z’| ≥ 3 are considered unsatisfactory

The overall results of z’-score are presented in tables of exceedances and surface plots hereafter and in laboratory-specific bar plots in Annex C.

5.3.1   PM10 z’-scores

Figure 16 shows the z’-scores for PM10 measurements for each participant (vertical axis) and each day (horizontal axis) in colour scale from -5 (dark blue) to +5 (dark red). Entries for which no data were available have been assigned the value “9” in this figure. PM10 data from Participant B led to numerous high (>2) and low (<-2) z’-scores. Participants C, M and P reported PM10 data generally biased high, while Participants I and O reported PM10 data generally biased low.

Figure 16: z’-scores for PM10 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown. Entries >4.5 (also dark brown) are labelled with their value (e.g. 4.6).

Table 6 summarises the z’-scores for all PM10 results. 2.8% of the daily values were considered as “questionable” and 2.6 % as “unsatisfactory”.

Table 6: Summary z’-scores for PM10

Total daily averages with z’-score

1470

Daily averages in the range: 2 < |z’| < 3

41

2.8 %

Daily averages in the range: |z’| ≥ 3

38

2.6 %

5.3.2   PM2.5 z’-scores

Figure 17 shows the z’-scores for PM2.5 measurements similarly to Figure 16 above. Participants C, M and P reported PM2.5 data generally biased high, while participants I, and O reported PM2.5 data generally biased low.

Figure 17: z’-scores for PM2.5 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Table 7 summarises the z’-score for all PM2.5 results. 5.7 % of the daily averages were considered as “questionable” and 0.7 % as “unsatisfactory”.

Table 7: Summary z’-score for PM2.5

Total daily averages with z’-score

1203

Daily averages in the range: 2 < |z’| < 3

68

5.7 %

Daily averages in the range: |z’| ≥ 3

8

0.7 %

5.4  En-scores

The En-scores are calculated according to ISO 13528:2015 as:

Equation 11

(En)i=xi-xptU2(xi)+U2(xpt)

where xi is a participants’ value, xpt is the Assigned Value, U(xi) is the participants’ value expanded uncertainty and U(xpt) is the expanded uncertainty of the Assigned Value. Participants’ uncertainties were taken “as reported” (see Chapter 5.5).

Successful performance is indicated by |En| < 1, scores of |En| ≥ 1 indicate either a need to review the uncertainty estimates or an erroneous measurement result.

The results of the En-scores are presented in figures and tables of exceedances hereafter. Further Annex D, in bar plots for each laboratory, presents the bias of each participant (xi-xpt) with error bars showing the denominator of the equation 11 (U2(xi)+U2(xpt)). These plots represent also the En-scores where, considering the En criterion (|En|<1), all results with error bars crossing the x-axis are satisfactory.

5.4.1   PM10 En-scores

Figure 18 shows the En-scores for PM10 measurements for each participant (vertical axis) and each day (horizontal axis) in a colour scale ranging from-3 (dark blue) to +3 (dark red), similarly to Figure 16. Participants B reported a large amount of data leading to both En-scores ≤-1 and En-scores ≥+1. Participants C, L, P and Y reported a significant (>18%) fraction of PM10 values leading to En-scores ≥+1, while Participants I, and O reported a significant (>16%) fraction of values leading to En-scores ≤-1.

Figure 18: En-scores for PM10 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Table 8 summarises the En-score for all PM10 results. 6.3 % of the daily averages exceeded the |En| - criterion.

Table 8: Summary En-score for PM10

Total daily averages with En-scores

1470

Daily averages with |En| ≥ 1

93

6.3 %

5.4.2   PM2.5 En-scores

Figure 19 shows the En-scores for PM2.5 measurements for each participant (vertical axis) and each day (horizontal axis) similarly to Figure 16. Participants B, I, and O reported a significant (>39%) fraction of values leading to En-scores ≤-1, while Participants C, L, M, P and Y reported a significant (>10%) fraction of values leading to En-scores ≥+1. These results are very similar to those observed for PM10 En-scores.

Figure 19: En-scores for PM2.5 measurements in colour scale (left hand side) as a function of days (horizontal axis) and participant code (vertical axis). Missing values are shown as dark brown.

Table 9 summarises the En-score for all PM2.5 results. 9.3 % of the daily averages exceeded the |En| - criterion.

Table 9: Summary En-score for PM2.5

Total daily averages with En-scores

1203

Daily averages with |En| ≥ 1

112

9.3 %

5.5  Uncertainties of participants results

To better understand the results of the En-scores, a closer look was given to the participants’ reported uncertainties and the uncertainty calculated for the Assigned Value. Most of the participants calculated their uncertainties with respect to the measured concentration, but some gave a constant (or more or less constant) figure for the whole measurement period. Especially on days with higher concentrations, major ‘dynamics’ in the expressed uncertainties can be observed. This led to considerable differences between the participants, worst on the day with the highest measured PM concentration (measurement day 31, 17 February 2018), where expanded uncertainties between 0.06 and 8.5 μg/m³ were reported. This report does not apply an upper limit for uncertainties. Hence, applying expanded uncertainties well above 2*σpt might facilitate reaching a successful En-score. Figure 20 and 21 present the reported expanded uncertainties for PM10 and PM2.5; for better interpretation the expanded uncertainty of the Assigned Value is shown in a ‘solid black line’ and the 2* σpt in a ‘dashed black line’, too.

An attentional review of the calculation of uncertainties in line with EN 12341:2014 is strongly recommended to the participants, as this has a direct influence on the En-score (see Equation 11).

Figure 20: Expanded uncertainties of all participants’ PM10 data and the Assigned Value (in solid black), 2*σpt (in dashed black)

Figure 21: Expanded uncertainties of all participants’ PM2.5 data and the Assigned Value (in solid black), 2*σpt (in dashed black)

Further, to better visualise the dependency of uncertainty on concentration, Figure 22 (PM10) and Figure 23 (PM2.5) present the ratio of expanded uncertainty vs. PM concentration:

Figure 22: Expanded uncertainties vs. concentration of all participants’ PM10 data

Figure 23: Expanded uncertainties vs. concentration of all participants’ PM2.5 data

5.6  Reproducibility

The reproducibility of the method s(R) [9] was calculated (excluding blunders but including outliers and stragglers) firstly from all daily values and secondly of daily values when the Assigned Value exceeded 75% of the daily limit value (50 μg/m³) or the annual limit value (25 μg/m³) for PM10 and PM2.5, respectively. Table 10 lists the reproducibility of PM10 and PM2.5 measurements for the entire field comparison exercise.

Table 10: Reproducibility for PM10 and PM2.5 of the field comparison exercise

PM10

s(R) in %

participants

days

all data

11

28

56

data ≥ 37.5 μg/m³

7

28

18

data ≥ 18.75 μg/m³

PM2.5

s(R) in %

participants

days

11

23

56

8

23

42

Multiplying these figures with a coverage factor of 2 (95% probability) gives an indication of the overall uncertainty of PM10 and PM2.5 measurements. Hence, both the expanded uncertainty at the limit value of PM10 (13.5%) and PM2.5 (16%) would comply with the DQO of the European Directive 2008/50/EC (25%).

In a second stage, the reproducibility was calculated for each single day and confronted with the corresponding concentration (Figures 24 and 25). As expected, the reproducibility depends on the measured concentration with a tendency to worsen at low concentration levels. Apart from a few cases, where outliers strongly affect the results (e.g. for PM10 at a concentration level of 24 μg/m³), the reproducibility is quite homogenous at the various concentration levels.

Figure 24: PM10 method reproducibility versus concentration

Figure 25: PM2.5 method reproducibility versus concentration

Conclusion

For the present inter-laboratory comparison exercise, assigned daily values for PM10 and PM2.5 were computed as the robust average of all participants using the standard gravimetric method (EN12341:2014). From statistical evaluations of the results some major conclusions have been drawn.

After blunder removal, the performance of the participants was evaluated by Grubb’s test, z’- scores and En-scores:

• Three values for PM10 of one laboratory were removed as obvious blunders.

• Through Grubb’s test 26 values of PM10 (1.8% of the total results submitted) and 1 of PM2.5 (0.1% of the total results submitted) were found to be outliers. Most of the outliers can be attributed to one laboratory only.

• For z’-scores, 2.6% of the results for PM10 and only 0.7% for PM2.5 were found not satisfactory (|z’|≥3). Apart from two, all of the unsatisfactory entries for PM10 were produced by one single participant.

• For En-scores, 6.3% of the values of PM10 and 9.3% of the values of PM2.5 exceeded the test threshold (|En|≥1). This suggests that the expanded uncertainty of the measurements provided by some participants was underestimated, hence it is warmly recommended to calculate the uncertainty according to EN 12341:2014 [2].

The robustness of the measurement method was assessed by computing its reproducibility:

• The overall reproducibility of the method was 11% for both PM10 and PM2.5, when including the whole measurement range. At a level around the limit values and above the method reproducibility was found to be 7% and 8% for PM10 and PM2.5, respectively.

References

[1] Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe, L 152, 11.06.2008, with amendments of Commission Directive (EU) 2015/1480 of 28 August 2015

[2] EN 12341:2014, Ambient air - Standard gravimetric measurement method for the determination of the PM10 or PM2.5 mass concentration of suspended particulate matter

[3] http//ies.jrc.ec.europa.eu/aquila-project/aquila-homepage.html

[4] E. de Saeger, M. Gerboles, H. Rau, M. Payrissat. European comparison of Nitrogen Dioxide calibration methods quality assurance programme n 1, QAP/1 of the European Directive for Nitrogen Dioxide. EUR 17661.

[5] F. Lagler, C. Belis, A. Borowiak. A quality Assurance and Control Programme for PM 2.5 and PM10 measurements in European Air Quality Monitoring Networks. EUR 24851. 2011

[6] Lagler F. et al. Evaluation of the Field Comparison Exercise for PM10 and PM2.5, Ispra, February 13th – April 9th, 2015. EUR 28107. 2016

[7] ISO 17025:2005, General Requirements for the Competence of Testing and Calibration Laboratories

[8] ISO 13528:2015, Statistical methods for use in proficiency testing by interlaboratory comparisons

[9] ISO 5725-2:1994, Accuracy (trueness and precision) of measurement methods and results – Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method

Annex A: Assigned Values and associated expanded uncertainties (k=2)

Table 11: Assigned Values for PM10 and PM2.5 from 18 January to 16 February

PM10

PM2.5

day

x(pt)

U(xpt)

x(pt)

U(xpt)

18-Jan-18

13.84

2.45

9.80

2.38

19-Jan-18

18.94

2.46

15.40

2.40

20-Jan-18

11.42

2.45

8.66

2.40

21-Jan-18

5.79

2.40

4.80

2.34

22-Jan-18

23.66

2.45

19.37

2.53

23-Jan-18

55.36

2.85

47.79

2.76

24-Jan-18

64.17

2.91

55.28

2.88

25-Jan-18

43.55

2.63

38.94

2.83

26-Jan-18

39.28

2.66

37.39

2.61

27-Jan-18

12.31

2.39

11.12

2.39

28-Jan-18

23.40

2.45

20.84

2.54

29-Jan-18

29.74

2.44

27.24

2.48

30-Jan-18

38.05

2.56

33.22

2.62

31-Jan-18

63.74

2.71

57.53

2.91

1-Feb-18

33.54

2.53

27.65

2.87

2-Feb-18

19.80

2.44

15.93

2.37

3-Feb-18

27.02

2.45

23.35

2.43

4-Feb-18

27.22

2.54

23.90

2.48

5-Feb-18

22.30

2.50

20.23

2.58

6-Feb-18

25.39

2.43

23.49

2.50

7-Feb-18

23.87

2.47

20.65

2.48

8-Feb-18

28.19

2.41

23.98

2.59

9-Feb-18

26.06

2.45

22.75

2.45

10-Feb-18

20.55

2.51

17.06

2.47

11-Feb-18

40.69

2.60

36.80

2.66

12-Feb-18

36.91

2.56

32.85

2.62

13-Feb-18

11.54

2.40

9.28

2.38

14-Feb-18

24.45

2.48

20.44

2.55

15-Feb-18

44.80

2.69

38.98

2.78

16-Feb-18

61.73

2.70

54.73

2.86

Table 12: Assigned Values for PM10 and PM2.5 from 17 February to 14 March

PM10

PM2.5

day

x(pt)

U(xpt)

x(pt)

U(xpt)

17-Feb-18

76.63

2.73

69.22

2.83

18-Feb-18

57.64

2.78

48.00

2.87

19-Feb-18

23.82

2.37

19.86

2.45

20-Feb-18

43.58

2.63

39.11

2.53

21-Feb-18

34.08

2.42

30.52

2.48

22-Feb-18

38.07

2.48

33.98

2.57

23-Feb-18

22.50

2.38

21.54

2.48

24-Feb-18

31.74

2.47

29.33

2.52

25-Feb-18

22.46

2.38

19.17

2.48

26-Feb-18

27.86

2.43

20.60

2.53

27-Feb-18

25.27

2.40

21.63

2.47

28-Feb-18

44.46

2.55

39.10

2.45

1-Mar-18

59.72

2.51

56.82

2.60

2-Mar-18

56.77

2.54

54.53

2.74

3-Mar-18

25.11

2.36

24.29

2.48

4-Mar-18

33.50

2.51

30.86

2.69

5-Mar-18

41.75

2.47

38.51

2.67

6-Mar-18

31.90

2.44

29.18

2.45

7-Mar-18

44.81

2.51

39.09

2.62

8-Mar-18

17.04

2.46

14.77

2.43

9-Mar-18

25.08

2.44

17.91

2.48

10-Mar-18

27.70

2.40

23.44

2.54

11-Mar-18

9.81

2.38

8.72

2.43

12-Mar-18

14.07

2.34

12.07

2.44

13-Mar-18

15.96

2.42

13.22

2.49

14-Mar-18

9.19

2.38

5.69

2.44

Annex B: Participants’ data

Table 13: Participants’ value PM10 lab code from A to H

PM10

A

B

C

D

E

F

G

H

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

13.40

4.50

18.50

3.40

14.94

2.58

1.96

1.12

14.80

3.70

12.43

3.36

13.84

3.33

12.19

2.86

19-Jan-18

18.50

4.50

26.10

3.40

20.64

2.62

3.29

1.12

20.08

3.82

18.39

3.40

20.04

3.36

18.07

2.95

20-Jan-18

11.50

4.50

20.80

3.40

13.55

2.57

4.31

1.12

12.03

3.66

11.43

3.36

12.77

3.32

9.68

2.83

21-Jan-18

5.70

4.50

9.20

3.40

7.67

2.54

1.09

1.12

8.30

3.62

5.90

3.34

6.17

3.30

4.84

2.79

22-Jan-18

24.70

4.50

28.60

3.40

26.09

2.68

2.14

1.12

24.58

3.92

22.98

3.42

24.47

3.40

22.92

3.04

23-Jan-18

56.80

4.50

43.30

3.60

59.11

3.23

8.51

1.12

52.63

5.00

53.60

3.82

57.78

3.85

53.90

4.03

24-Jan-18

64.00

4.50

54.00

3.80

70.02

3.47

14.91

1.13

62.29

5.46

63.00

3.98

67.86

4.04

62.86

4.39

25-Jan-18

44.00

4.50

36.00

3.60

46.74

2.98

9.68

1.12

42.54

4.56

42.02

3.64

45.10

3.64

42.77

3.61

26-Jan-18

40.10

4.50

31.40

3.60

42.70

2.91

9.69

1.12

36.54

4.32

38.40

3.58

40.79

3.58

37.79

3.45

27-Jan-18

12.10

4.50

20.10

3.40

14.65

2.58

1.29

1.12

12.15

3.36

12.70

3.32

11.29

2.85

28-Jan-18

23.90

4.50

95.40

4.60

25.06

2.67

5.95

1.12

25.56

3.96

22.71

3.42

24.26

3.40

22.32

3.03

29-Jan-18

30.60

4.50

28.60

3.40

32.47

2.76

1.34

1.12

31.37

4.14

29.52

3.48

30.67

3.46

28.78

3.19

30-Jan-18

39.70

4.50

30.50

3.60

41.77

2.90

4.32

1.12

37.10

4.34

37.63

3.58

39.25

3.56

37.20

3.43

31-Jan-18

66.60

4.50

54.90

3.80

68.56

3.43

21.59

1.64

61.68

5.42

61.84

3.96

63.04

3.95

63.64

4.42

01-Feb-18

34.40

4.50

130.00

5.60

37.40

2.83

26.71

2.03

31.15

4.12

32.77

3.52

33.76

3.49

33.51

3.32

02-Feb-18

19.90

4.50

26.10

3.40

22.74

2.64

4.64

1.12

20.68

3.82

19.95

3.40

20.11

3.36

19.60

2.98

03-Feb-18

27.50

4.50

25.40

3.40

29.95

2.72

5.88

1.12

27.44

4.00

26.50

3.46

27.36

3.42

26.87

3.14

04-Feb-18

27.90

4.50

32.80

3.60

30.45

2.73

7.20

1.12

25.46

3.94

25.62

3.44

27.85

3.43

26.93

3.14

05-Feb-18

22.20

4.50

21.60

3.40

24.71

2.66

5.69

1.12

20.56

3.82

21.87

3.42

23.10

3.39

21.58

3.02

06-Feb-18

26.20

4.50

26.30

3.40

28.96

2.71

2.81

1.12

24.55

3.92

24.58

3.44

25.93

3.41

25.31

3.10

07-Feb-18

23.80

4.50

39.40

3.60

27.15

2.69

4.09

1.12

23.89

3.90

23.79

3.44

24.71

3.40

23.27

3.05

08-Feb-18

28.40

4.50

17.20

3.40

32.29

2.75

5.15

1.12

27.53

4.02

27.33

3.46

28.81

3.44

28.22

3.17

09-Feb-18

27.20

4.50

22.80

3.40

29.82

2.72

7.38

1.12

25.12

3.94

25.59

3.44

27.05

3.42

25.90

3.11

10-Feb-18

21.50

4.50

13.00

3.40

22.64

2.64

5.28

1.12

22.36

3.86

20.13

3.40

25.15

3.40

20.13

2.99

11-Feb-18

42.60

4.50

22.10

3.40

45.45

2.96

2.14

1.12

40.86

4.48

40.05

3.62

39.55

3.56

40.55

3.54

12-Feb-18

40.30

4.50

15.90

3.40

39.67

2.86

18.15

1.38

38.68

4.40

36.23

3.56

36.96

3.53

36.71

3.42

13-Feb-18

12.30

4.50

1.30

3.40

13.33

2.57

0.58

1.12

12.56

3.66

11.11

3.36

12.42

3.32

11.41

2.85

14-Feb-18

26.40

4.50

13.20

3.40

27.69

2.70

3.99

1.12

24.50

3.92

24.10

3.44

25.04

3.40

24.38

3.08

15-Feb-18

44.70

4.50

31.70

3.60

48.81

3.02

9.11

1.12

46.60

4.72

41.65

3.64

45.05

3.64

44.81

3.69

16-Feb-18

61.80

4.50

48.40

3.80

67.17

3.40

12.49

1.12

65.91

5.64

59.76

3.64

62.32

3.94

60.96

4.31

17-Feb-18

78.10

4.50

64.00

4.00

81.67

3.75

22.11

1.68

79.82

6.38

74.42

4.22

76.16

4.22

75.99

4.96

18-Feb-18

58.20

4.50

45.80

3.60

62.49

3.30

20.04

1.52

60.00

5.34

55.87

3.86

57.01

3.84

57.51

4.17

19-Feb-18

24.00

4.50

0.50

3.40

25.93

2.68

2.93

1.12

23.13

3.88

22.95

3.42

25.00

3.40

23.08

3.05

20-Feb-18

44.20

4.50

33.20

3.60

47.44

3.00

8.35

1.12

46.67

4.72

41.45

3.62

41.56

3.59

43.28

3.63

21-Feb-18

35.20

4.50

26.90

3.40

37.17

2.82

7.66

1.12

36.70

4.32

34.42

3.54

33.76

3.49

33.75

3.33

22-Feb-18

39.00

4.50

19.00

3.40

42.14

2.90

9.63

1.12

39.54

4.44

37.21

3.58

38.04

3.55

38.02

3.46

23-Feb-18

22.60

4.50

8.30

3.40

26.09

2.68

6.32

1.12

22.53

3.88

22.50

3.42

22.12

3.03

24-Feb-18

31.30

4.50

19.90

3.40

34.98

2.79

3.07

1.12

32.56

4.18

31.36

3.50

31.48

3.47

31.50

3.26

25-Feb-18

24.10

4.50

10.30

3.40

24.39

2.66

6.20

1.12

21.65

3.84

22.84

3.42

22.14

3.38

22.62

3.04

26-Feb-18

29.60

4.50

16.10

3.40

29.98

2.72

9.49

1.12

26.84

3.96

27.74

3.46

27.32

3.42

28.18

3.17

27-Feb-18

26.70

4.50

9.80

3.40

28.05

2.70

8.06

1.12

24.32

3.92

25.39

3.44

26.11

3.41

25.15

3.10

28-Feb-18

45.60

4.50

38.40

3.60

48.09

3.01

9.83

1.12

44.31

4.62

46.21

3.70

43.62

3.62

43.23

3.63

01-Mar-18

61.20

4.50

58.50

4.00

64.43

3.34

10.15

1.12

63.23

5.50

58.91

3.90

60.49

3.90

58.12

4.19

02-Mar-18

58.40

4.50

56.10

3.80

61.88

3.28

14.23

1.12

59.56

5.32

55.49

3.84

56.92

3.84

54.74

4.06

03-Mar-18

24.70

4.50

35.10

3.60

27.76

2.70

3.92

1.12

23.21

3.88

25.16

3.44

26.56

3.42

24.48

3.08

04-Mar-18

33.00

4.50

35.90

3.60

37.75

2.83

2.73

1.12

33.28

4.20

32.97

3.52

34.75

3.50

32.21

3.28

05-Mar-18

41.80

4.50

46.29

2.98

21.12

1.61

42.56

4.56

41.08

3.62

43.04

3.61

40.10

3.52

06-Mar-18

32.10

4.50

39.30

3.60

35.67

2.80

8.23

1.12

31.75

4.14

31.80

3.52

32.88

3.48

31.32

3.26

07-Mar-18

45.00

4.50

42.40

3.60

48.90

3.02

7.10

1.12

45.82

4.68

43.35

3.66

45.34

3.65

43.53

3.64

08-Mar-18

18.40

4.50

13.60

3.40

18.81

2.61

5.90

1.12

17.56

3.76

17.49

3.38

16.97

3.34

15.90

2.91

09-Mar-18

26.20

4.50

26.80

3.40

26.74

2.68

4.77

1.12

24.56

3.92

24.10

3.44

25.94

3.41

24.92

3.09

10-Mar-18

28.20

4.50

17.00

3.40

30.61

2.73

7.20

1.12

25.82

3.96

25.00

3.44

28.93

3.44

27.31

3.15

11-Mar-18

9.60

4.50

14.70

3.40

12.25

2.56

5.59

1.12

12.66

3.66

9.84

3.36

9.49

3.31

8.40

2.82

12-Mar-18

13.80

4.50

13.40

3.40

16.83

2.59

0.89

1.12

15.14

3.38

14.00

3.33

13.71

2.88

13-Mar-18

17.90

4.50

20.70

3.40

17.79

2.60

7.78

1.12

17.56

3.76

16.49

3.38

14.06

3.33

15.14

2.90

14-Mar-18

10.60

4.50

16.00

3.40

10.38

2.55

2.02

1.12

9.81

3.62

9.20

3.34

8.45

2.82

Table 14: Participants’ value PM10 lab code from I to P

PM10

I

J

K

L

M

N

O

P

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

12.06

0.72

15.84

3.76

15.23

0.43

15.35

2.05

16.34

2.35

12.50

2.40

9.14

2.73

14.14

1.09

19-Jan-18

16.70

0.98

21.02

3.87

20.68

0.62

21.38

2.16

20.96

2.45

18.00

2.50

14.26

2.75

19.77

1.52

20-Jan-18

9.41

0.57

13.60

3.69

11.79

0.33

12.83

2.04

13.54

2.23

10.20

2.40

7.04

2.72

12.15

0.94

21-Jan-18

5.10

0.35

9.00

3.62

6.08

0.18

7.34

2.17

8.54

2.15

5.20

2.30

2.00

2.70

22-Jan-18

20.70

1.21

25.94

4.01

22.67

0.66

26.24

2.13

25.71

2.52

22.90

2.60

19.40

2.79

25.58

1.97

23-Jan-18

51.39

2.97

57.67

5.38

54.24

1.52

59.78

2.30

56.36

3.70

55.70

3.90

51.23

3.28

59.49

4.58

24-Jan-18

59.85

3.46

67.88

5.93

62.76

1.82

67.28

2.20

63.82

4.04

64.90

4.40

60.10

3.48

68.37

5.26

25-Jan-18

41.11

2.38

45.57

4.79

42.45

1.19

47.67

2.17

44.38

3.19

44.20

3.40

40.52

3.08

47.15

3.63

26-Jan-18

36.83

2.13

41.73

4.62

38.54

1.12

44.70

2.09

44.51

3.19

39.20

3.20

36.76

3.02

42.62

3.28

27-Jan-18

10.66

0.64

15.42

3.76

12.43

0.36

14.39

2.06

11.60

2.40

8.94

2.72

14.15

1.09

28-Jan-18

20.91

1.22

23.71

4.00

22.58

0.66

25.51

2.03

22.50

2.60

20.06

2.80

24.67

1.90

29-Jan-18

29.15

1.69

30.76

4.20

29.75

0.83

32.45

2.30

28.00

2.80

27.40

2.88

31.56

2.43

30-Jan-18

35.51

2.06

39.28

4.53

36.28

1.05

41.69

2.07

41.24

3.06

37.10

3.10

35.24

2.99

40.44

3.11

31-Jan-18

60.68

3.51

64.04

5.71

63.03

1.64

67.21

2.28

65.44

4.11

62.00

4.20

62.22

3.53

67.13

5.17

1-Feb-18

29.13

1.69

36.27

4.37

32.38

0.94

36.56

2.08

33.72

2.78

33.10

3.00

28.56

2.90

35.19

2.71

2-Feb-18

17.11

1.01

21.45

3.87

18.77

0.54

21.56

2.09

22.03

2.42

19.00

2.50

16.78

2.77

3-Feb-18

23.85

1.39

29.20

4.11

27.12

0.79

29.66

2.04

27.46

2.57

26.20

2.70

24.64

2.85

28.29

2.18

4-Feb-18

23.44

1.37

28.78

4.11

26.57

0.77

30.58

2.15

28.56

2.61

26.50

2.80

24.15

2.84

28.66

2.21

5-Feb-18

18.33

1.08

25.05

4.01

21.13

0.61

25.13

2.09

22.22

2.42

23.20

2.70

26.66

2.05

6-Feb-18

21.89

1.28

26.97

4.06

23.04

0.65

24.67

2.08

25.87

2.53

25.60

2.70

21.97

2.82

27.93

2.15

7-Feb-18

20.00

1.17

25.33

3.98

22.31

0.63

26.85

2.08

25.35

2.51

24.10

2.70

20.22

2.80

26.12

2.01

8-Feb-18

24.30

1.42

30.05

4.14

27.75

0.78

32.30

2.17

29.88

2.65

28.20

2.80

25.41

2.86

30.83

2.37

9-Feb-18

22.07

1.29

27.90

4.08

25.30

0.73

28.85

2.12

27.25

2.57

26.50

2.80

22.71

2.83

29.02

2.24

10-Feb-18

16.98

1.00

22.64

3.91

20.77

0.60

23.15

2.10

22.18

2.42

20.00

2.60

17.41

2.78

22.31

1.72

11-Feb-18

38.04

2.20

43.66

4.69

39.36

1.18

45.67

2.15

40.59

3.04

41.10

3.30

37.31

3.03

43.35

3.34

12-Feb-18

33.09

1.92

41.20

4.58

34.83

1.01

40.68

2.19

38.36

2.95

37.70

3.20

33.56

2.97

13-Feb-18

9.75

0.59

13.76

3.72

11.61

0.34

12.94

2.05

13.32

2.22

10.50

2.40

7.92

2.72

12.51

0.96

14-Feb-18

21.57

1.26

26.26

4.03

24.03

0.63

27.07

2.20

26.40

2.54

23.40

2.70

21.30

2.81

25.58

1.97

15-Feb-18

43.36

2.51

45.50

4.80

46.98

1.32

48.36

2.14

46.60

3.28

44.40

3.40

40.83

3.09

47.52

3.66

16-Feb-18

58.47

3.38

61.32

5.57

64.76

1.88

66.24

2.31

64.27

4.06

61.50

4.20

58.09

3.43

65.29

5.03

17-Feb-18

72.28

4.18

76.99

6.43

78.26

2.27

78.93

2.23

78.06

4.71

76.70

5.00

72.50

3.78

80.54

6.20

18-Feb-18

52.44

3.03

58.23

5.41

60.21

1.81

60.79

2.24

60.54

3.89

58.20

4.10

53.61

3.33

61.84

4.76

19-Feb-18

21.31

1.24

24.12

3.97

23.13

0.67

25.98

2.07

26.99

2.56

23.90

2.70

20.07

2.80

27.39

2.11

20-Feb-18

41.26

2.39

43.76

4.69

46.70

1.40

46.89

2.15

46.07

3.26

44.10

3.40

39.92

3.07

47.16

3.63

21-Feb-18

31.60

1.83

34.44

4.31

35.37

0.99

33.06

2.07

36.29

1.88

34.20

3.00

31.65

2.94

36.82

2.84

22-Feb-18

34.58

2.01

37.59

4.43

38.64

1.12

38.94

2.08

41.08

3.06

38.60

3.20

33.79

2.97

45.16

3.48

23-Feb-18

19.63

1.15

23.03

3.93

21.76

0.61

25.20

2.04

24.49

2.49

21.70

2.60

19.47

2.79

23.58

1.82

24-Feb-18

29.48

1.71

32.23

4.22

30.20

0.88

35.41

2.06

35.00

2.83

32.90

3.00

28.08

2.89

34.10

2.63

25-Feb-18

20.50

1.20

22.25

3.94

20.22

0.59

24.28

2.05

25.69

2.52

22.80

2.60

20.97

2.81

21.76

1.67

26-Feb-18

25.40

1.48

26.84

4.07

25.21

0.76

29.33

2.06

31.23

2.70

28.20

2.80

26.27

2.87

28.11

2.16

27-Feb-18

22.73

1.33

26.17

4.06

23.85

0.69

26.63

2.03

29.01

2.62

25.40

2.70

23.53

2.84

25.75

1.98

28-Feb-18

42.57

2.47

44.33

4.76

42.72

1.32

47.15

2.10

48.47

3.37

44.60

3.40

40.73

3.08

44.80

3.46

1-Mar-18

56.96

3.29

59.93

5.51

59.59

1.85

61.54

2.19

61.48

3.93

59.90

4.10

56.86

3.41

60.75

4.69

2-Mar-18

53.79

3.11

59.68

5.48

56.87

1.65

58.02

2.15

58.13

3.78

57.60

4.00

52.89

3.32

58.75

4.53

3-Mar-18

24.47

1.43

26.60

4.04

26.47

2.10

28.40

2.60

24.90

2.70

23.07

2.83

28.84

2.21

4-Mar-18

33.79

1.96

35.36

4.34

34.42

2.10

37.31

2.91

33.70

3.00

30.15

2.92

38.64

2.98

5-Mar-18

41.29

2.39

43.49

4.67

43.33

2.16

46.00

3.26

41.40

3.30

39.08

3.06

45.88

3.54

6-Mar-18

28.91

1.68

32.64

4.21

33.41

2.11

34.95

2.83

31.20

2.90

29.65

2.91

36.82

2.84

7-Mar-18

42.19

2.44

46.72

4.82

46.48

2.16

47.44

3.32

44.70

3.40

41.50

3.10

49.69

3.82

8-Mar-18

16.00

0.94

16.79

3.76

18.64

2.05

20.20

2.37

15.20

2.50

13.52

2.75

19.41

1.50

9-Mar-18

23.59

1.37

24.28

3.94

27.54

2.08

29.52

2.64

23.70

2.70

22.47

2.82

30.11

2.31

10-Mar-18

25.99

1.51

27.88

4.06

28.69

2.08

31.03

2.69

27.80

2.80

24.53

2.85

31.20

2.40

11-Mar-18

7.93

0.49

10.01

3.65

10.98

2.06

13.64

2.46

8.70

2.30

6.49

2.71

12.69

0.98

12-Mar-18

12.13

0.72

14.59

3.70

15.80

2.06

16.76

2.54

13.00

2.40

11.07

2.73

17.95

1.38

13-Mar-18

14.52

0.86

16.63

3.74

17.99

2.05

19.19

2.61

14.00

2.40

12.51

2.74

19.22

1.48

14-Mar-18

8.45

0.52

10.85

3.63

9.77

2.06

13.73

2.46

7.50

2.30

4.95

2.71

Table 15: Participants’ value PM10 lab code from Q to X

PM10

Q

R

S

T

U

V

W

X

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

13.38

1.98

13.00

1.00

13.62

3.37

14.00

2.90

13.85

1.21

11.60

3.00

13.11

1.95

19-Jan-18

18.25

1.01

18.00

1.40

15.95

3.29

19.10

3.40

18.70

2.90

19.30

1.21

16.50

3.00

18.26

2.02

20-Jan-18

10.55

1.56

11.00

0.90

9.73

3.26

11.10

3.35

10.70

2.80

11.31

1.21

10.30

3.00

10.44

1.91

21-Jan-18

5.48

0.81

5.00

0.40

3.52

3.25

5.32

3.34

5.70

2.40

5.59

1.21

4.20

3.00

4.67

1.87

22-Jan-18

22.76

1.26

23.00

1.80

21.67

3.33

24.66

3.44

23.40

3.00

23.92

1.21

22.50

3.10

23.19

2.12

23-Jan-18

55.86

3.10

52.00

4.20

53.31

3.72

58.23

3.92

56.40

5.90

53.00

3.50

24-Jan-18

64.97

3.60

58.00

4.60

62.12

3.87

66.40

4.08

67.50

7.00

63.00

3.70

25-Jan-18

43.63

2.42

41.00

3.30

42.15

3.55

45.78

3.70

43.50

4.60

41.00

3.30

26-Jan-18

39.59

2.19

38.00

3.00

38.76

3.50

38.60

4.10

39.00

3.30

27-Jan-18

11.92

1.77

11.00

0.90

10.94

3.27

12.77

3.36

13.00

2.90

12.94

1.21

11.00

3.00

11.97

1.93

28-Jan-18

24.05

1.33

22.00

1.80

22.30

3.33

24.14

3.44

23.40

3.00

22.20

3.10

29-Jan-18

29.15

1.62

29.00

2.30

27.67

3.38

30.81

3.51

29.20

3.30

28.50

3.10

30-Jan-18

37.82

2.10

37.00

3.00

36.76

3.48

39.81

3.62

37.80

4.00

36.30

3.20

31-Jan-18

64.32

3.56

58.00

4.60

64.52

3.92

65.10

6.70

63.90

3.70

01-Feb-18

33.81

1.87

33.76

3.44

32.60

3.60

31.60

1.34

33.40

3.20

02-Feb-18

19.23

1.07

18.29

3.31

20.03

3.41

18.70

2.90

19.10

3.00

19.43

2.04

03-Feb-18

26.97

1.49

25.20

3.36

27.77

3.47

25.90

3.10

26.50

3.10

26.56

2.19

04-Feb-18

27.25

1.51

25.75

3.36

28.04

3.48

26.10

3.10

26.10

2.18

05-Feb-18

22.88

1.27

21.53

3.33

23.89

3.44

20.00

2.90

21.40

2.08

06-Feb-18

25.48

1.41

25.16

3.36

26.81

3.46

23.80

3.00

25.33

2.23

07-Feb-18

23.77

1.32

23.00

1.80

22.61

3.34

24.88

3.45

22.40

3.00

22.90

3.10

23.08

2.12

08-Feb-18

28.71

1.59

28.00

2.20

27.46

3.38

29.81

3.49

27.30

3.20

27.31

1.21

27.60

3.10

27.43

2.21

09-Feb-18

26.37

1.46

26.00

2.10

25.62

3.36

27.27

3.47

25.10

3.10

25.05

1.21

25.40

3.10

25.40

2.17

10-Feb-18

19.50

1.08

19.00

1.50

18.83

3.31

21.42

3.42

20.40

2.90

24.24

1.21

18.50

3.00

19.85

2.05

11-Feb-18

42.81

2.37

40.00

3.20

39.51

3.51

42.98

3.66

40.70

4.30

39.93

1.34

39.30

3.30

38.63

2.59

12-Feb-18

37.48

2.08

36.00

2.90

35.90

3.47

38.50

3.60

37.10

4.00

34.58

1.34

36.60

3.20

36.24

2.44

13-Feb-18

10.72

1.59

12.00

1.00

11.46

3.27

11.73

3.36

11.60

2.90

10.45

1.21

10.60

3.00

11.07

1.92

14-Feb-18

26.33

1.46

25.00

2.00

23.85

3.35

24.89

3.45

25.40

3.10

23.16

1.21

22.20

3.10

23.73

2.13

15-Feb-18

44.00

3.50

43.82

3.57

48.10

5.00

43.40

3.30

45.27

2.72

16-Feb-18

60.00

4.80

60.75

3.85

61.84

3.99

65.50

6.80

60.30

3.60

17-Feb-18

76.54

4.24

73.00

5.80

76.22

4.15

77.53

4.31

81.80

8.50

76.20

4.00

18-Feb-18

56.52

3.13

55.00

4.40

56.32

3.77

63.57

4.13

61.90

6.40

56.08

1.34

56.40

3.50

19-Feb-18

23.15

1.28

23.00

1.80

23.88

3.35

24.36

3.44

24.30

3.10

23.94

1.21

23.80

3.10

23.73

2.13

20-Feb-18

44.27

2.45

42.00

3.40

43.02

3.56

44.77

3.69

46.70

4.90

42.00

1.34

43.10

3.30

43.58

2.66

21-Feb-18

34.24

1.90

33.00

2.60

33.06

3.44

35.05

3.55

34.60

3.70

33.20

1.34

34.20

3.20

34.16

2.39

22-Feb-18

38.79

2.15

36.00

2.90

37.33

3.49

39.12

3.61

41.20

4.30

36.76

1.34

38.50

3.20

37.42

2.48

23-Feb-18

23.19

1.29

22.00

1.80

22.01

3.33

23.42

3.43

23.60

3.00

21.88

1.21

22.10

3.10

22.41

2.10

24-Feb-18

31.99

1.77

30.00

2.40

31.12

3.42

33.05

3.53

33.60

3.70

30.96

1.34

32.10

3.20

31.68

2.32

25-Feb-18

22.85

1.27

22.00

1.80

23.01

3.34

23.62

3.44

23.50

3.00

22.06

1.21

22.20

3.10

23.17

2.12

26-Feb-18

28.61

1.59

27.00

2.20

28.91

3.39

29.31

3.49

27.20

3.20

28.56

1.21

28.70

3.10

28.75

2.24

27-Feb-18

27.03

1.50

25.00

2.00

25.45

3.36

26.42

3.46

25.20

3.10

25.20

1.21

21.70

3.10

25.77

2.17

28-Feb-18

43.00

3.40

46.31

3.61

44.81

3.69

47.10

4.90

43.70

3.30

44.78

2.83

01-Mar-18

59.00

3.27

58.00

4.60

60.74

3.85

65.20

6.80

57.48

1.34

60.00

3.60

59.87

3.21

02-Mar-18

56.13

3.11

54.00

4.30

56.24

3.77

57.96

3.91

61.60

6.40

54.61

1.34

56.80

3.60

03-Mar-18

24.84

1.38

25.00

2.00

24.71

3.35

26.30

3.46

26.20

3.20

23.43

1.21

25.00

3.10

24.58

2.15

04-Mar-18

34.00

1.88

32.00

2.60

32.45

3.43

34.90

3.55

36.70

3.90

31.30

1.34

33.60

3.20

32.07

2.33

05-Mar-18

41.15

2.28

40.00

3.20

40.98

3.53

42.63

3.66

43.60

4.60

39.10

1.34

40.50

3.30

42.24

2.89

06-Mar-18

30.85

1.71

31.00

2.50

31.75

3.42

32.54

3.53

33.00

3.60

29.32

1.21

31.50

3.20

30.41

2.29

07-Mar-18

43.60

2.42

44.00

3.50

43.52

3.57

45.84

3.71

47.20

4.90

44.50

3.30

46.70

3.20

08-Mar-18

19.05

1.06

19.00

1.50

15.88

3.29

16.88

3.39

18.20

2.90

15.02

1.21

15.70

3.00

16.78

2.00

09-Mar-18

24.56

1.36

26.00

2.10

23.96

3.35

25.93

3.46

25.70

3.10

23.64

1.21

23.40

3.10

24.35

2.14

10-Mar-18

27.65

1.53

28.00

2.20

28.23

3.39

28.94

3.49

27.90

3.30

26.26

1.21

27.10

3.10

27.09

2.20

11-Mar-18

9.48

1.41

10.00

0.80

10.00

3.26

9.91

3.35

9.10

2.80

8.77

1.21

9.50

3.00

9.85

1.91

12-Mar-18

14.16

2.10

14.00

1.10

14.05

3.28

14.78

3.37

14.20

2.90

13.69

1.21

13.90

3.00

14.24

1.96

13-Mar-18

15.61

0.87

16.00

1.30

15.31

3.29

16.02

3.38

17.00

2.90

14.30

1.21

15.00

3.00

15.65

1.98

14-Mar-18

8.68

1.29

10.00

0.80

9.19

3.26

8.59

3.35

9.10

2.80

7.13

1.21

9.10

3.00

8.41

1.89

Table 16: Participants’ value PM10 lab code from Y to AD and σpt

PM10

Y

Z

AB

AC

AD

All

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

σpt

18-Jan-18

16.00

0.22

12.12

3.62

12.45

0.86

14.61

2.78

15.13

3.33

1.64

19-Jan-18

20.00

0.18

17.50

3.73

17.33

1.20

18.93

1.25

20.11

3.36

1.66

20-Jan-18

20.00

0.18

9.63

3.58

9.44

0.65

11.42

2.17

12.77

3.32

1.64

21-Jan-18

7.00

0.51

4.78

3.54

4.49

0.31

5.79

1.10

6.32

3.30

1.63

22-Jan-18

24.00

0.15

20.93

3.82

21.54

1.49

23.82

1.57

24.11

3.40

1.67

23-Jan-18

59.00

0.07

50.81

5.02

56.85

3.75

58.20

3.86

1.89

24-Jan-18

67.00

0.06

60.04

5.50

65.33

4.31

65.96

4.01

1.97

25-Jan-18

46.00

0.08

40.28

4.52

44.52

2.93

44.98

3.64

1.79

26-Jan-18

42.00

0.09

37.14

4.39

29.64

2.05

40.48

2.67

39.75

3.57

1.76

27-Jan-18

13.00

0.27

11.62

3.61

11.85

0.82

12.88

2.45

12.03

3.32

1.64

28-Jan-18

48.00

0.08

22.05

3.85

23.28

1.53

24.22

3.40

1.67

29-Jan-18

31.00

0.12

28.10

4.04

30.14

1.99

29.94

3.45

1.70

30-Jan-18

40.00

0.09

35.53

4.32

38.52

2.54

38.95

3.56

1.75

31-Jan-18

67.00

0.06

60.58

5.53

65.83

4.34

62.85

3.95

1.96

01-Feb-18

35.00

0.11

31.15

4.15

35.57

2.34

33.65

3.49

1.72

02-Feb-18

21.00

0.17

18.06

3.74

18.30

1.26

20.27

1.34

20.27

3.36

1.66

03-Feb-18

29.00

0.13

25.06

3.94

25.03

1.73

27.68

1.82

30.77

3.46

1.69

04-Feb-18

29.00

0.13

24.65

3.92

25.15

1.74

28.39

1.87

27.84

3.43

1.69

05-Feb-18

24.00

0.15

20.27

3.80

20.09

1.39

23.41

1.54

21.45

3.37

1.67

06-Feb-18

27.00

0.14

23.75

3.90

24.15

1.67

27.05

1.78

25.37

3.41

1.68

07-Feb-18

25.00

0.15

22.21

3.85

21.30

1.47

24.78

1.63

24.12

3.40

1.68

08-Feb-18

31.00

0.12

26.48

3.98

26.59

1.84

30.02

1.98

28.35

3.43

1.70

09-Feb-18

28.00

0.13

24.61

3.92

24.27

1.67

27.69

1.83

25.27

3.41

1.69

10-Feb-18

21.00

0.17

19.68

3.78

18.48

1.28

20.38

1.34

20.93

3.37

1.66

11-Feb-18

44.00

0.09

38.59

4.45

37.20

2.57

42.50

2.80

40.30

3.57

1.77

12-Feb-18

39.00

0.10

35.80

4.33

35.12

2.42

37.84

2.49

36.12

3.52

1.74

13-Feb-18

13.00

0.27

10.66

3.60

9.90

0.68

12.42

2.36

11.07

3.31

1.64

14-Feb-18

27.00

0.14

22.64

3.86

22.14

1.53

24.72

1.63

23.99

3.39

1.68

15-Feb-18

48.00

0.08

41.84

4.59

41.24

2.85

44.61

2.94

43.81

3.62

1.80

16-Feb-18

63.00

0.07

58.54

5.42

60.55

3.99

60.38

3.90

1.94

17-Feb-18

80.00

0.06

73.09

6.24

75.26

4.96

75.33

4.20

2.10

18-Feb-18

59.00

0.07

54.64

5.22

56.20

3.70

55.58

3.81

1.91

19-Feb-18

24.00

0.15

22.93

3.87

21.77

1.50

24.44

1.61

23.57

3.39

1.68

20-Feb-18

45.00

0.09

39.75

4.50

40.94

2.83

43.16

2.84

42.15

3.60

1.79

21-Feb-18

35.00

0.11

32.71

4.21

32.35

2.23

33.17

2.19

34.05

3.50

1.73

22-Feb-18

40.00

0.09

36.55

4.36

35.53

2.45

38.30

2.52

36.37

3.52

1.75

23-Feb-18

24.00

0.15

22.04

3.85

20.72

1.43

22.88

1.51

1.67

24-Feb-18

33.00

0.11

29.79

4.10

30.09

2.08

31.63

2.08

31.16

3.46

1.71

25-Feb-18

24.00

0.15

21.78

3.84

21.10

1.46

22.55

1.49

21.78

3.38

1.67

26-Feb-18

30.00

0.12

26.44

3.98

26.32

1.82

28.49

1.88

26.55

3.42

1.69

27-Feb-18

24.81

3.93

24.01

1.66

25.35

1.67

24.43

3.40

1.68

28-Feb-18

46.00

0.08

42.20

4.61

44.15

2.91

42.52

3.61

1.80

01-Mar-18

61.00

0.07

56.86

5.33

55.43

3.83

60.01

3.96

59.59

3.88

1.93

02-Mar-18

57.00

0.07

53.71

5.17

55.94

3.69

55.96

3.82

1.90

03-Mar-18

25.00

0.15

24.52

3.92

23.26

1.61

25.24

1.66

24.54

3.40

1.68

04-Mar-18

30.00

0.12

31.94

4.18

30.75

2.12

33.28

2.19

33.28

3.49

1.72

05-Mar-18

42.00

0.09

39.50

4.49

41.15

2.71

41.17

3.59

1.78

06-Mar-18

31.00

0.12

30.55

4.13

31.81

2.10

33.14

3.49

1.72

07-Mar-18

44.00

0.09

41.00

4.55

44.52

2.93

44.71

3.64

1.80

08-Mar-18

16.00

0.22

26.59

3.99

16.04

1.11

16.46

1.08

16.66

3.34

1.65

09-Mar-18

31.00

0.12

23.07

3.88

23.53

1.62

25.57

1.69

24.70

3.40

1.68

10-Mar-18

28.00

0.13

25.74

3.96

28.44

1.87

28.12

3.43

1.69

11-Mar-18

9.00

0.39

10.04

3.59

9.41

0.65

10.00

1.90

9.05

3.31

1.63

12-Mar-18

14.00

0.26

13.77

3.65

13.77

0.95

14.77

2.81

12.36

3.32

1.64

13-Mar-18

16.00

0.22

14.87

3.67

14.87

1.03

15.56

1.03

15.78

3.34

1.65

14-Mar-18

9.00

0.39

8.65

3.57

8.26

0.57

10.27

1.95

1.63

Table 17: Participants’ value PM2.5 lab code from A to H

PM2.5

A

B

C

D

E

F

G

H

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

10.00

1.60

13.20

3.40

11.90

2.56

1.23

0.97

11.93

3.66

9.05

3.34

10.25

3.31

9.34

2.82

19-Jan-18

15.40

1.60

15.60

3.40

18.39

2.60

2.03

0.97

18.97

3.78

14.62

3.38

16.51

3.34

14.64

2.89

20-Jan-18

8.20

1.60

8.20

3.40

10.65

2.55

2.14

0.97

9.33

3.62

7.77

3.34

9.14

3.31

8.08

2.81

21-Jan-18

4.70

1.60

6.65

2.54

0.63

0.97

8.61

3.62

4.77

3.34

5.05

3.30

4.04

2.78

22-Jan-18

17.70

1.60

20.60

3.40

22.96

2.64

1.26

0.97

19.67

3.80

17.91

3.40

18.98

3.36

18.91

2.96

23-Jan-18

47.10

1.60

54.46

3.13

5.47

0.97

44.79

4.64

43.91

3.66

49.82

3.72

46.27

3.73

24-Jan-18

56.50

1.60

42.20

3.60

63.50

3.32

8.87

0.97

53.91

3.06

51.66

3.78

57.54

3.85

53.51

4.01

25-Jan-18

37.80

1.60

45.16

2.96

6.47

0.97

36.23

4.30

36.47

3.56

39.15

3.56

38.90

3.48

26-Jan-18

36.80

1.60

41.64

2.90

8.33

0.97

36.68

3.56

37.74

3.54

37.27

3.43

27-Jan-18

11.70

1.60

9.31

2.55

0.82

0.97

12.14

3.66

10.17

3.36

10.93

3.31

10.23

2.83

28-Jan-18

21.00

1.60

24.20

2.66

4.19

0.97

21.71

3.84

19.81

3.40

19.67

3.36

20.40

2.99

29-Jan-18

26.70

1.60

31.16

2.74

1.20

0.97

28.43

4.04

25.93

3.46

27.94

3.43

26.60

3.13

30-Jan-18

32.80

1.60

37.98

2.84

3.56

0.97

32.83

4.18

32.33

3.52

33.95

3.49

33.05

3.30

31-Jan-18

56.30

1.60

60.73

3.26

16.40

1.56

55.00

3.10

53.84

3.82

58.55

3.87

57.40

4.16

01-Feb-18

25.90

1.60

20.00

3.40

31.74

2.75

21.76

2.07

26.61

3.98

27.75

3.46

28.56

3.44

02-Feb-18

15.60

1.60

20.00

3.40

18.29

2.60

1.98

0.97

16.34

3.74

15.92

3.38

16.68

3.34

15.29

2.90

03-Feb-18

23.10

1.60

18.60

3.40

27.18

2.69

3.59

0.97

22.84

3.88

23.12

3.42

23.60

3.39

22.81

3.04

04-Feb-18

22.80

1.60

19.40

3.40

27.38

2.69

4.80

0.97

23.09

3.88

23.29

3.44

24.73

3.40

23.68

3.06

05-Feb-18

19.80

1.60

23.82

2.65

3.79

0.97

19.05

3.78

19.61

3.40

17.16

3.34

19.68

2.97

06-Feb-18

22.40

1.60

20.70

3.40

26.54

2.68

1.89

0.97

23.38

3.90

22.21

3.42

24.47

3.40

23.12

3.04

07-Feb-18

20.00

1.60

15.60

3.40

24.07

2.66

2.24

0.97

20.47

3.82

19.93

3.40

19.97

3.36

20.73

2.99

08-Feb-18

23.70

1.60

27.54

2.69

2.03

0.97

23.69

3.90

22.64

3.42

21.04

3.37

24.59

3.08

09-Feb-18

21.60

1.60

22.50

3.40

25.86

2.68

4.86

0.97

21.85

3.86

21.75

3.42

22.94

3.39

23.30

3.05

10-Feb-18

17.40

1.60

20.43

2.62

3.23

0.97

20.82

3.82

17.07

3.38

14.48

3.33

16.05

2.91

11-Feb-18

35.50

1.60

40.39

2.87

1.57

0.97

36.94

4.34

35.99

3.56

36.31

3.52

37.26

3.43

12-Feb-18

32.90

1.60

35.52

2.80

15.40

1.46

34.27

4.24

31.86

3.52

31.04

3.46

31.69

3.26

13-Feb-18

8.40

1.60

10.51

2.55

0.40

0.97

10.18

3.64

9.76

3.36

8.78

3.30

8.73

2.82

14-Feb-18

18.80

1.60

24.00

2.66

2.36

0.97

20.39

3.82

20.80

3.42

19.37

3.36

20.35

2.99

15-Feb-18

35.90

1.60

44.57

2.95

4.98

0.97

39.39

4.42

37.91

3.58

39.04

3.56

38.94

3.48

16-Feb-18

53.20

1.60

60.39

3.25

7.71

0.97

57.25

3.22

51.61

3.78

54.30

3.79

53.48

4.01

17-Feb-18

69.70

1.60

75.68

3.60

14.55

1.38

67.27

5.72

67.39

4.06

68.61

4.06

68.45

4.62

18-Feb-18

50.40

1.60

36.30

3.60

54.88

3.14

17.19

1.63

48.86

4.82

49.68

3.76

47.28

3.68

48.30

3.81

19-Feb-18

17.70

1.60

22.49

2.64

1.73

0.97

19.59

3.80

19.75

3.40

20.49

3.37

19.93

2.98

20-Feb-18

37.80

1.60

43.24

2.92

5.02

0.97

41.60

4.52

38.86

3.60

38.03

3.54

38.92

3.48

21-Feb-18

30.40

1.60

25.30

3.40

33.33

2.77

5.35

0.97

32.39

4.16

31.10

3.50

30.19

3.45

29.67

3.21

22-Feb-18

33.20

1.60

38.34

2.84

5.60

0.97

36.10

4.30

32.90

3.52

33.40

3.49

34.60

3.35

23-Feb-18

20.30

1.60

25.22

2.67

4.81

0.97

21.73

3.86

19.70

3.40

21.76

3.38

20.96

3.00

24-Feb-18

28.60

1.60

34.14

2.78

2.47

0.97

29.78

4.08

27.62

3.46

29.12

3.44

29.42

3.20

25-Feb-18

17.40

1.60

8.50

3.40

21.84

2.63

3.81

0.97

18.98

3.78

20.14

3.40

19.65

3.36

18.98

2.96

26-Feb-18

20.10

1.60

14.90

3.40

22.86

2.64

3.77

0.97

19.12

3.78

23.20

3.42

20.38

3.37

21.23

3.00

27-Feb-18

20.40

1.60

23.68

2.65

3.16

0.97

22.31

3.86

22.33

3.42

23.02

3.39

21.67

3.01

28-Feb-18

38.90

1.60

42.69

2.91

5.58

0.97

39.48

4.42

40.04

3.62

38.68

3.55

38.43

3.47

01-Mar-18

59.00

1.60

55.80

3.80

61.95

3.29

5.55

0.97

60.69

5.38

56.22

3.86

56.78

3.83

55.15

4.07

02-Mar-18

57.40

1.60

50.80

3.80

61.10

3.27

11.40

1.08

57.42

5.22

54.22

3.82

54.58

3.80

53.19

3.99

03-Mar-18

28.90

1.60

22.50

3.40

28.02

2.70

3.39

0.97

22.78

3.88

24.48

3.44

24.65

3.40

23.85

3.06

04-Mar-18

33.90

1.60

28.30

3.40

36.12

2.81

2.29

0.97

30.81

4.12

31.82

3.52

31.41

3.47

29.02

3.19

05-Mar-18

41.30

1.60

42.16

2.90

19.23

1.83

39.81

4.44

39.11

3.60

38.55

3.55

37.05

3.42

06-Mar-18

33.00

1.60

29.70

3.40

32.94

2.76

6.23

0.97

28.63

4.04

29.68

3.48

29.92

3.45

28.49

3.17

07-Mar-18

42.90

1.60

39.10

3.60

43.61

2.93

5.43

0.97

40.39

4.46

39.10

3.60

37.81

3.54

39.27

3.49

08-Mar-18

17.10

1.60

18.17

2.60

4.60

0.97

16.66

3.74

15.17

3.60

13.87

3.33

13.82

2.88

09-Mar-18

18.00

1.60

21.49

2.63

2.12

0.97

19.33

3.80

19.01

3.40

17.25

3.34

17.25

2.93

10-Mar-18

24.90

1.60

27.73

2.70

3.07

0.97

21.84

3.86

23.91

3.44

24.12

3.40

23.43

3.05

11-Mar-18

10.20

1.60

10.74

2.55

3.99

0.97

9.30

3.62

9.77

3.36

8.32

3.30

7.75

2.81

12-Mar-18

12.10

1.60

16.22

2.59

0.59

0.97

13.66

3.68

13.54

3.36

11.74

3.32

11.03

2.84

13-Mar-18

16.30

1.60

16.27

2.59

4.14

0.97

15.36

3.72

14.27

3.38

13.34

3.32

12.44

2.86

14-Mar-18

5.70

1.60

8.13

2.54

0.71

0.97

7.55

3.60

6.80

3.34

5.61

3.30

4.99

2.79

Table 18: Participants’ value PM2.5 lab code from I to P. (Laboratory J did not install instruments for PM2.5 measurements)

PM.5

I

J

K

L

M

N

O

P

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

9.14

0.79

7.70

0.22

10.87

2.04

13.52

2.23

9.20

2.40

4.40

2.20

10.69

1.24

19-Jan-18

13.57

1.16

14.42

0.40

16.97

2.02

19.67

2.36

14.80

2.60

10.54

2.23

16.87

1.96

20-Jan-18

6.92

0.61

8.98

0.26

10.11

2.02

13.59

2.23

8.20

2.40

3.94

2.20

9.80

1.14

21-Jan-18

4.56

0.43

4.99

0.16

6.44

2.01

8.66

2.16

4.60

2.30

2.00

2.19

22-Jan-18

16.73

1.42

20.13

0.56

22.19

2.03

22.76

2.44

19.20

2.80

14.88

2.26

21.22

2.47

23-Jan-18

42.04

3.55

49.52

1.49

49.98

2.09

50.25

3.43

48.10

4.70

43.55

2.71

50.42

5.86

24-Jan-18

49.14

4.15

56.87

1.59

58.27

2.15

58.07

3.78

55.30

5.20

50.48

2.87

58.59

6.78

25-Jan-18

35.56

3.01

38.63

1.08

41.89

2.07

42.38

3.11

39.50

4.00

32.35

2.49

40.09

4.64

26-Jan-18

31.05

2.63

37.36

1.08

39.72

2.06

39.59

3.00

37.10

3.90

33.64

2.51

39.36

4.55

27-Jan-18

8.54

0.75

11.61

0.34

12.71

2.03

15.89

2.27

10.80

2.50

7.67

2.21

12.52

1.45

28-Jan-18

17.39

1.48

21.04

0.59

22.65

2.03

24.82

2.49

20.20

2.90

17.11

2.28

22.49

2.61

29-Jan-18

23.84

2.02

26.84

0.78

28.64

2.04

30.13

2.66

26.20

3.20

24.38

2.37

28.84

3.36

30-Jan-18

27.68

2.34

33.65

0.98

37.08

2.10

35.30

2.84

32.00

3.50

29.74

2.45

35.56

4.14

31-Jan-18

50.54

4.27

56.59

1.59

60.12

2.13

59.24

3.83

56.00

5.30

55.34

2.98

60.40

6.98

01-Feb-18

20.58

1.75

28.39

0.82

30.29

2.13

30.75

2.68

23.26

2.35

30.48

3.55

02-Feb-18

14.25

1.22

15.60

0.47

16.00

2.05

19.15

2.34

15.50

2.60

13.23

2.25

03-Feb-18

21.16

1.80

22.95

0.67

25.66

2.05

25.92

2.53

23.30

3.00

21.88

2.33

26.48

3.07

04-Feb-18

21.10

1.79

24.03

0.70

27.56

2.08

26.73

2.55

23.50

3.00

21.60

2.33

27.39

3.17

05-Feb-18

15.41

1.31

20.04

0.58

20.05

2.10

22.79

2.47

21.30

2.90

23.40

2.72

06-Feb-18

19.58

1.66

22.67

0.64

23.88

2.06

25.25

2.51

23.50

3.00

20.39

2.32

27.57

3.21

07-Feb-18

17.80

1.51

19.32

0.56

23.42

2.08

23.25

2.45

20.90

2.90

17.05

2.28

25.03

2.91

08-Feb-18

20.76

1.76

23.94

0.69

25.27

2.04

26.02

2.53

24.30

3.10

20.83

2.32

28.84

3.35

09-Feb-18

17.92

1.52

21.58

0.60

25.62

2.05

24.59

2.49

23.20

3.00

19.31

2.30

26.85

3.13

10-Feb-18

14.64

1.25

16.60

0.48

19.87

2.06

19.69

2.36

16.60

2.70

14.09

2.25

21.59

2.51

11-Feb-18

33.08

2.80

37.54

1.16

39.98

2.12

39.11

2.98

36.70

3.90

33.32

2.51

41.36

4.81

12-Feb-18

28.05

2.38

33.38

0.97

36.38

2.09

35.31

2.84

32.90

3.60

29.72

2.45

13-Feb-18

4.70

0.44

8.52

0.25

10.94

2.06

11.30

2.19

8.60

2.40

5.46

2.20

10.88

1.27

14-Feb-18

18.01

1.53

22.22

0.62

23.18

2.12

22.87

2.44

19.10

2.80

17.23

2.28

21.95

2.55

15-Feb-18

35.34

2.99

40.62

1.18

41.93

2.07

41.76

3.08

38.50

4.00

34.54

2.53

42.63

4.96

16-Feb-18

49.71

4.20

56.23

1.69

58.99

2.14

57.32

3.74

53.10

5.00

50.39

2.86

56.96

6.62

17-Feb-18

60.20

5.09

70.56

2.05

75.15

2.20

71.63

4.40

68.50

6.20

66.09

3.26

72.91

8.50

18-Feb-18

40.51

3.43

50.05

1.55

52.08

2.14

51.04

3.47

46.50

4.50

45.42

2.75

52.98

6.14

19-Feb-18

16.99

1.45

19.13

0.56

22.81

2.03

22.56

2.43

20.00

2.80

17.39

2.28

21.05

2.43

20-Feb-18

35.67

3.02

40.18

1.25

39.88

2.08

40.79

3.05

39.30

4.00

35.82

2.55

40.45

4.70

21-Feb-18

27.90

2.36

32.20

0.97

30.33

2.05

32.99

2.76

30.50

3.40

28.04

2.42

31.38

3.63

22-Feb-18

29.46

2.49

35.91

1.11

37.10

2.07

35.71

2.85

33.80

3.70

30.50

2.46

35.73

4.14

23-Feb-18

17.10

1.46

20.68

0.60

24.37

2.04

24.03

2.47

22.80

3.00

18.98

2.30

22.86

2.66

24-Feb-18

24.45

2.07

28.75

0.83

32.73

2.05

30.70

2.68

30.60

3.50

26.73

2.40

33.01

3.85

25-Feb-18

17.24

1.47

17.50

0.51

21.00

2.04

21.64

2.41

19.20

2.80

17.03

2.28

20.31

2.35

26-Feb-18

19.09

1.62

19.32

0.56

23.66

2.06

23.34

2.45

20.40

2.90

18.35

2.29

21.22

2.45

27-Feb-18

19.12

1.63

19.50

0.57

23.34

2.06

23.64

2.46

20.50

2.90

19.14

2.30

23.22

2.69

28-Feb-18

35.54

3.01

38.72

1.12

41.36

2.11

40.21

3.02

40.00

4.10

34.65

2.53

38.46

4.47

01-Mar-18

53.51

4.52

58.12

1.69

58.99

2.20

58.70

3.80

56.90

5.30

54.14

2.95

58.23

6.76

02-Mar-18

49.26

4.16

55.05

1.60

56.98

2.18

56.35

3.70

54.70

5.20

51.28

2.89

58.24

6.74

03-Mar-18

22.65

1.92

25.80

2.15

26.61

2.55

24.10

3.10

21.03

2.32

26.66

3.10

04-Mar-18

29.33

2.48

32.50

2.08

35.85

2.86

30.50

3.40

28.16

2.42

35.01

4.06

05-Mar-18

35.47

3.00

41.18

2.11

43.01

3.13

38.00

3.90

36.22

2.56

40.27

4.68

06-Mar-18

27.48

2.33

30.63

2.09

32.88

2.75

28.30

3.30

26.05

2.39

31.20

3.63

07-Mar-18

38.26

3.24

41.24

2.18

42.88

3.13

38.20

4.00

33.98

2.52

41.73

4.85

08-Mar-18

14.92

1.27

15.56

2.02

18.93

2.34

13.30

2.60

10.69

2.23

15.24

1.78

09-Mar-18

15.59

1.33

20.65

2.06

20.35

2.37

17.00

2.70

14.79

2.26

18.32

2.12

10-Mar-18

20.99

1.78

25.60

2.06

26.02

2.53

23.10

3.00

19.23

2.30

26.84

3.10

11-Mar-18

7.26

0.64

8.69

2.10

12.28

2.42

7.80

2.40

4.96

2.20

10.70

1.24

12-Mar-18

10.43

0.90

13.24

2.06

16.63

2.52

11.20

2.50

7.91

2.21

13.43

1.56

13-Mar-18

11.70

1.01

12.13

2.24

16.00

2.51

8.00

2.40

7.95

2.21

13.24

1.54

14-Mar-18

4.52

0.42

6.44

2.06

8.80

2.33

2.00

2.19

Table 19: Participants’ value PM2.5 lab code from Q to X (Laboratory R and U did not install instruments for PM2.5 measurements)

PM2.5

Q

R

S

T

U

V

W

X

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

18-Jan-18

9.77

2.12

9.35

3.26

9.96

3.35

9.04

1.14

7.90

2.90

9.46

1.92

19-Jan-18

15.33

1.22

14.72

3.29

16.14

3.38

14.85

1.14

13.50

2.90

14.80

2.00

20-Jan-18

8.53

1.85

8.55

3.26

8.80

3.35

8.41

1.14

6.60

2.90

7.90

1.90

21-Jan-18

4.88

1.06

5.16

3.25

4.73

3.34

4.41

1.14

2.80

2.90

4.25

1.87

22-Jan-18

19.22

1.52

18.08

3.30

20.62

3.41

19.47

1.25

17.50

2.90

18.88

2.08

23-Jan-18

48.57

3.85

44.32

3.58

49.75

3.77

44.70

3.30

48.88

3.53

24-Jan-18

56.93

4.52

52.33

3.70

57.73

3.91

52.20

3.40

25-Jan-18

40.15

3.18

37.00

3.48

41.63

3.64

37.80

3.20

26-Jan-18

37.81

3.00

35.66

3.47

39.48

3.61

36.00

3.10

27-Jan-18

11.38

0.90

10.78

3.27

11.72

3.36

11.59

1.14

10.10

2.90

10.91

1.94

28-Jan-18

19.95

1.58

18.57

3.31

22.14

3.42

21.47

1.25

19.10

3.00

21.10

2.13

29-Jan-18

26.26

2.08

26.21

3.37

28.60

3.48

25.90

3.00

27.92

2.65

30-Jan-18

32.42

2.57

31.61

3.42

35.27

3.56

32.00

3.10

33.09

2.68

31-Jan-18

57.74

4.58

60.16

3.95

58.10

3.50

01-Feb-18

28.04

2.22

26.52

1.25

27.60

3.00

28.06

2.32

02-Feb-18

15.88

1.26

15.86

3.29

17.11

3.39

14.63

1.14

14.30

2.90

15.98

2.02

03-Feb-18

23.99

1.90

18.82

3.31

25.07

3.45

22.43

1.25

22.90

3.00

23.56

2.20

04-Feb-18

24.73

1.96

23.77

3.35

25.59

3.45

22.80

1.25

22.30

3.00

23.71

2.20

05-Feb-18

21.74

1.72

20.17

3.32

23.01

3.43

19.36

1.25

19.30

3.00

20.17

2.11

06-Feb-18

24.32

1.93

23.86

3.35

25.77

3.45

22.33

1.25

22.40

3.00

23.57

2.20

07-Feb-18

21.63

1.72

20.42

3.32

22.65

3.43

19.73

1.25

19.50

3.00

20.61

2.12

08-Feb-18

25.42

2.02

23.38

3.34

26.56

3.46

22.79

1.25

21.10

3.00

23.70

2.20

09-Feb-18

23.83

1.89

22.81

3.34

24.65

3.44

21.55

1.25

21.30

3.00

22.39

2.17

10-Feb-18

17.39

1.38

16.03

3.29

18.58

3.40

15.82

1.14

16.00

2.90

16.95

2.04

11-Feb-18

38.42

3.05

35.37

3.46

39.24

3.61

34.39

1.25

35.60

3.10

35.37

2.47

12-Feb-18

34.49

2.74

32.26

3.43

35.15

3.56

30.25

1.25

32.90

3.10

32.79

2.47

13-Feb-18

8.85

1.92

9.63

3.26

9.71

3.35

8.48

1.14

8.90

2.90

8.91

1.91

14-Feb-18

20.88

1.66

20.05

3.32

21.45

3.42

20.52

1.25

17.60

2.90

18.88

2.08

15-Feb-18

40.11

3.18

38.37

3.50

36.89

1.25

38.51

2.67

16-Feb-18

55.07

4.37

55.06

3.75

55.94

3.87

17-Feb-18

70.60

5.60

68.14

3.99

70.96

4.17

68.50

3.70

18-Feb-18

47.36

3.76

43.68

3.57

50.63

3.78

47.07

1.25

48.00

3.30

47.46

3.01

19-Feb-18

20.86

1.65

20.49

3.32

20.62

3.41

19.59

1.25

18.60

3.00

19.26

2.09

20-Feb-18

40.70

3.23

38.33

3.50

40.33

3.62

38.19

1.25

37.90

3.20

21-Feb-18

32.37

2.57

30.61

3.41

31.66

3.51

30.20

1.25

29.30

3.10

29.87

2.38

22-Feb-18

36.15

2.87

33.08

3.44

34.98

3.55

32.93

1.25

32.30

3.10

32.63

2.47

23-Feb-18

23.10

1.83

21.81

3.33

22.47

3.42

20.86

1.25

21.30

3.00

20.52

2.12

24-Feb-18

30.45

2.42

28.88

3.39

31.06

3.51

29.01

1.25

28.70

3.00

28.65

2.34

25-Feb-18

19.70

1.56

20.89

3.32

20.09

3.41

18.60

1.25

17.90

2.90

18.78

2.08

26-Feb-18

21.73

3.33

22.11

3.42

20.51

1.25

19.70

3.00

19.89

2.11

27-Feb-18

22.11

1.75

22.71

3.34

22.57

3.43

21.05

1.25

20.40

3.00

20.56

2.12

28-Feb-18

39.43

3.51

39.20

3.20

37.55

2.70

01-Mar-18

57.18

4.54

56.33

3.77

53.70

1.25

56.40

3.50

55.43

3.32

02-Mar-18

55.29

4.39

51.71

3.69

56.48

3.88

51.80

1.25

55.10

3.50

53.15

3.23

03-Mar-18

24.37

1.93

23.97

3.35

24.98

3.45

22.77

1.25

23.60

3.00

23.53

2.20

04-Mar-18

31.70

2.51

28.77

3.39

33.13

3.53

29.30

1.25

30.30

3.10

30.26

2.39

05-Mar-18

38.48

3.05

35.93

3.47

40.23

3.62

36.80

1.25

37.00

3.20

37.34

2.63

06-Mar-18

28.82

2.29

27.51

3.38

30.02

3.50

27.48

1.25

28.90

3.00

28.32

2.33

07-Mar-18

38.85

3.08

37.43

3.49

41.41

3.64

37.28

1.25

37.70

3.20

38.25

2.66

08-Mar-18

16.32

1.29

14.88

3.29

14.67

3.37

13.59

1.14

13.70

2.90

13.78

1.98

09-Mar-18

18.10

1.44

18.97

3.31

18.86

3.40

17.67

1.14

16.10

2.90

15.94

2.02

10-Mar-18

23.28

1.85

22.49

3.34

24.32

3.44

22.13

1.25

23.20

3.00

22.10

2.16

11-Mar-18

8.27

1.79

9.24

3.26

9.12

3.35

7.59

1.14

8.70

2.90

8.41

1.90

12-Mar-18

12.19

0.97

12.73

3.28

12.61

3.36

10.96

1.14

10.70

2.90

11.26

1.94

13-Mar-18

13.19

1.05

14.49

3.28

13.46

3.37

11.95

1.14

12.40

2.90

12.01

1.95

14-Mar-18

5.50

1.19

7.37

3.26

5.42

3.34

4.18

1.14

5.30

2.90

4.61

1.87

Table 20: Participants’ value PM2.5 lab code from Y to AD and σpt (Laboratory AB and AC did not install instruments for PM2.5 measurements)

PM2.5

Y

Z

AB

AC

AD

All

day

Avg

U

Avg

U

Avg

U

Avg

U

Avg

U

σpt

18-Jan-18

10.00

0.36

9.12

3.57

10.33

3.31

1.63

19-Jan-18

16.00

0.22

14.92

3.66

15.73

3.34

1.65

20-Jan-18

12.00

0.30

7.68

3.56

10.25

3.31

1.63

21-Jan-18

4.47

3.53

5.20

3.30

1.63

22-Jan-18

17.86

3.71

20.41

3.37

1.66

23-Jan-18

50.00

0.08

44.53

4.60

49.31

3.71

1.82

24-Jan-18

57.00

0.07

51.06

4.88

56.84

3.83

1.88

25-Jan-18

42.00

0.09

35.18

4.22

40.61

3.58

1.76

26-Jan-18

38.00

0.10

32.08

4.11

38.37

3.55

1.75

27-Jan-18

12.00

0.30

10.58

3.59

11.39

3.31

1.63

28-Jan-18

24.00

0.15

18.93

3.74

20.83

3.37

1.66

29-Jan-18

27.13

3.95

28.32

3.43

1.69

30-Jan-18

35.00

0.11

28.76

4.00

34.63

3.50

1.72

31-Jan-18

60.00

0.07

50.63

4.87

61.81

3.93

1.90

01-Feb-18

30.00

0.12

23.00

3.84

29.93

3.45

1.69

02-Feb-18

17.00

0.21

15.42

3.67

16.27

3.34

1.65

03-Feb-18

25.00

0.15

22.73

3.83

24.09

3.39

1.67

04-Feb-18

26.00

0.14

22.69

3.83

24.48

3.40

1.68

05-Feb-18

23.00

0.16

18.71

3.73

17.03

3.34

1.66

06-Feb-18

26.00

0.14

21.70

3.80

24.40

3.40

1.67

07-Feb-18

23.00

0.16

19.44

3.75

21.40

3.37

1.66

08-Feb-18

27.00

0.14

23.20

3.84

24.22

3.40

1.68

09-Feb-18

26.00

0.14

21.77

3.80

22.51

3.38

1.67

10-Feb-18

18.00

0.20

16.57

3.69

16.82

3.34

1.65

11-Feb-18

40.00

0.09

34.05

4.18

35.79

3.52

1.74

12-Feb-18

35.00

0.11

30.47

4.06

32.29

3.48

1.72

13-Feb-18

11.00

0.32

8.63

3.57

9.83

3.31

1.63

14-Feb-18

23.00

0.16

19.54

3.75

19.93

3.36

1.66

15-Feb-18

42.00

0.09

36.40

4.27

37.68

3.54

1.76

16-Feb-18

56.00

0.07

52.12

4.93

52.71

3.76

1.88

17-Feb-18

72.00

0.06

64.64

5.55

67.35

4.03

2.02

18-Feb-18

48.00

0.08

43.37

4.46

46.77

3.67

1.82

19-Feb-18

21.00

0.17

18.53

3.73

18.86

3.35

1.66

20-Feb-18

41.00

0.09

37.14

4.30

37.66

3.54

1.76

21-Feb-18

32.00

0.12

29.71

4.03

28.44

3.43

1.71

22-Feb-18

35.00

0.11

31.54

4.09

32.65

3.48

1.73

23-Feb-18

22.00

0.16

19.89

3.76

21.17

3.37

1.67

24-Feb-18

30.00

0.12

26.85

3.95

27.84

3.43

1.70

25-Feb-18

21.00

0.17

17.67

3.71

18.95

3.35

1.66

26-Feb-18

22.00

0.16

19.00

3.74

18.53

3.35

1.66

27-Feb-18

22.00

0.16

20.01

3.76

22.23

3.38

1.67

28-Feb-18

41.00

0.09

35.72

4.24

39.13

3.56

1.76

01-Mar-18

58.00

0.07

53.14

4.98

57.49

3.85

1.90

02-Mar-18

56.00

0.07

50.78

4.87

54.18

3.79

1.88

03-Mar-18

25.00

0.15

22.33

3.82

24.68

3.40

1.68

04-Mar-18

28.00

0.13

27.19

3.96

31.01

3.46

1.71

05-Mar-18

39.00

0.10

32.81

4.14

37.74

3.54

1.76

06-Mar-18

30.00

0.12

26.39

3.93

29.41

3.44

1.70

07-Mar-18

39.00

0.10

34.02

4.18

36.97

3.53

1.76

08-Mar-18

14.00

0.26

14.20

3.64

13.89

3.33

1.64

09-Mar-18

18.00

0.20

16.39

3.68

17.71

3.35

1.65

10-Mar-18

25.00

0.15

19.88

3.76

22.86

3.38

1.67

11-Mar-18

9.00

0.40

7.43

3.55

7.43

3.30

1.63

12-Mar-18

12.00

0.30

11.42

3.60

10.84

3.31

1.64

13-Mar-18

13.00

0.27

12.93

3.62

13.31

3.32

1.64

14-Mar-18

5.00

0.71

4.64

3.53

5.99

3.30

1.63

Annex C: Participants’ z’-scores

PM10

Figure 26 to 53 show for each laboratory the calculated z’-score daily value for PM10.

Figure 26: Chart of z’-score evaluation for PM10 related to Lab. A

Figure 27: Chart of z’-score evaluation for PM10 related to Lab. B

Figure 28: Chart of z’-score evaluation for PM10 related to Lab. C

Figure 29: Chart of z’-score evaluation for PM10 related to Lab. E

Figure 30: Chart of z’-score evaluation for PM10 related to Lab. F

Figure 31: Chart of z’-score evaluation for PM10 related to Lab. G

Figure 32: Chart of z’-score evaluation for PM10 related to Lab. H

Figure 33: Chart of z’-score evaluation for PM10 related to Lab. I

Figure 34: Chart of z’-score evaluation for PM10 related to Lab. J

Figure 35: Chart of z’-score evaluation for PM10 related to Lab. K

Figure 36: Chart of z’-score evaluation for PM10 related to Lab. L

Figure 37: Chart of z’-score evaluation for PM10 related to Lab. M

Figure 38: Chart of z’-score evaluation for PM10 related to Lab. N

Figure 39: Chart of z’-score evaluation for PM10 related to Lab. O

Figure 40: Chart of z’-score evaluation for PM10 related to Lab. P

Figure 41: Chart of z’-score evaluation for PM10 related to Lab. Q

Figure 42: Chart of z’-score evaluation for PM10 related to Lab. R

Figure 43: Chart of z’-score evaluation for PM10 related to Lab. S

Figure 44: Chart of z’-score evaluation for PM10 related to Lab. T

Figure 45: Chart of z’-score evaluation for PM10 related to Lab. U

Figure 46: Chart of z’-score evaluation for PM10 related to Lab. V

Figure 47: Chart of z’-score evaluation for PM10 related to Lab. W

Figure 48: Chart of z’-score evaluation for PM10 related to Lab. X

Figure 49: Chart of z’-score evaluation for PM10 related to Lab. Y

Figure 50:Chart of z’-score evaluation for PM10 related to Lab. Z

Figure 51: Chart of z’-score evaluation for PM10 related to Lab. AB

Figure 52: Chart of z’-score evaluation for PM10 related to Lab. AC

Figure 53: Chart of z’-score evaluation for PM10 related to Lab. AD

PM2.5

Figure 54 to 76 show for each laboratory the calculated z’-score daily value for PM2.5.

Figure 54: Chart of z’-score evaluation for PM2.5 related to Lab. A

Figure 55: Chart of z’-score evaluation for PM2.5 related to Lab. B

Figure 56: Chart of z’-score evaluation for PM2.5 related to Lab. C

Figure 57: Chart of z’-score evaluation for PM2.5 related to Lab. E

Figure 58: Chart of z’-score evaluation for PM2.5 related to Lab. F

Figure 59: Chart of z’-score evaluation for PM2.5 related to Lab. G

Figure 60: Chart of z’-score evaluation for PM2.5 related to Lab. H

Figure 61: Chart of z’-score evaluation for PM2.5 related to Lab. I

Figure 62: Chart of z’-score evaluation for PM2.5 related to Lab. K

Figure 63: Chart of z’-score evaluation for PM2.5 related to Lab. L

Figure 64: Chart of z’-score evaluation for PM2.5 related to Lab. M

Figure 65: Chart of z’-score evaluation for PM2.5 related to Lab. N

Figure 66: Chart of z’-score evaluation for PM2.5 related to Lab. O

Figure 67: Chart of z’-score evaluation for PM2.5 related to Lab. P

Figure 68: Chart of z’-score evaluation for PM2.5 related to Lab. Q

Figure 69: Chart of z’-score evaluation for PM2.5 related to Lab. S

Figure 70: Chart of z’-score evaluation for PM2.5 related to Lab. T

Figure 71: Chart of z’-score evaluation for PM2.5 related to Lab. V

Figure 72: Chart of z’-score evaluation for PM2.5 related to Lab. W

Figure 73: Chart of z’-score evaluation for PM2.5 related to Lab. X

Figure 74: Chart of z’-score evaluation for PM2.5 related to Lab. Y

Figure 75: Chart of z’-score evaluation for PM2.5 related to Lab. Z

Figure 76: Chart of z’-score evaluation for PM2.5 related to Lab. AD

Annex D: Participants’ En-scores

PM10

Figure 77 to 104 show for each laboratory the calculated En-score daily value for PM10.

Figure 77: Chart of Bias evaluation for PM10 related to Lab. A

Figure 78: Chart of Bias evaluation for PM10 related to Lab. B

Figure 79: Chart of Bias evaluation for PM10 related to Lab. C

Figure 80: Chart of Bias evaluation for PM10 related to Lab. E

Figure 81: Chart of Bias evaluation for PM10 related to Lab. F

Figure 82: Chart of Bias evaluation for PM10 related to Lab. G

Figure 83: Chart of Bias evaluation for PM10 related to Lab. H

Figure 84: Chart of Bias evaluation for PM10 related to Lab. I

Figure 85: Chart of Bias evaluation for PM10 related to Lab. J

Figure 86: Chart of Bias evaluation for PM10 related to Lab. K

Figure 87: Chart of Bias evaluation for PM10 related to Lab. L

Figure 88: Chart of Bias evaluation for PM10 related to Lab. M

Figure 89: Chart of Bias evaluation for PM10 related to Lab. N

Figure 90: Chart of Bias evaluation for PM10 related to Lab. O

Figure 91: Chart of Bias evaluation for PM10 related to Lab. P

Figure 92: Chart of Bias evaluation for PM10 related to Lab. Q

Figure 93: Chart of Bias evaluation for PM10 related to Lab. R

Figure 94: Chart of Bias evaluation for PM10 related to Lab. S

Figure 95: Chart of Bias evaluation for PM10 related to Lab. T

Figure 96: Chart of Bias evaluation for PM10 related to Lab. U

Figure 97: Chart of Bias evaluation for PM10 related to Lab. V

Figure 98: Chart of Bias evaluation for PM10 related to Lab. W

Figure 99: Chart of Bias evaluation for PM10 related to Lab. X

Figure 100: Chart of Bias evaluation for PM10 related to Lab. Y

Figure 101: Chart of Bias evaluation for PM10 related to Lab. Z

Figure 102: Chart of Bias evaluation for PM10 related to Lab. AB

Figure 103: Chart of Bias evaluation for PM10 related to Lab. AC

Figure 104: Chart of Bias evaluation for PM10 related to Lab. AD

PM2.5

Figure 105 to 127 show for each laboratory the calculated En-score daily value for PM2.5.

Figure 105: Chart of Bias evaluation for PM2.5 related to Lab. A

Figure 106: Chart of Bias evaluation for PM2.5 related to Lab. B

Figure 107: Chart of Bias evaluation for PM2.5 related to Lab. C

Figure 108: Chart of Bias evaluation for PM2.5 related to Lab. E

Figure 109: Chart of Bias evaluation for PM2.5 related to Lab. F

Figure 110: Chart of Bias evaluation for PM2.5 related to Lab. G

Figure 111: Chart of Bias evaluation for PM2.5 related to Lab. H

Figure 112: Chart of Bias evaluation for PM2.5 related to Lab. I

Figure 113: Chart of Bias evaluation for PM2.5 related to Lab. K

Figure 114: Chart of Bias evaluation for PM2.5 related to Lab. L

Figure 115: Chart of Bias evaluation for PM2.5 related to Lab. M

Figure 116: Chart of Bias evaluation for PM2.5 related to Lab. N

Figure 117: Chart of Bias evaluation for PM2.5 related to Lab. O

Figure 118: Chart of Bias evaluation for PM2.5 related to Lab. P

Figure 119: Chart of Bias evaluation for PM2.5 related to Lab. Q

Figure 120: Chart of Bias evaluation for PM2.5 related to Lab. S

Figure 121: Chart of Bias evaluation for PM2.5 related to Lab. T

Figure 122: Chart of Bias evaluation for PM2.5 related to Lab. V

Figure 123: Chart of Bias evaluation for PM2.5 related to Lab. W

Figure 124: Chart of Bias evaluation for PM2.5 related to Lab. X

Figure 125: Chart of Bias evaluation for PM2.5 related to Lab. Y

Figure 126: Chart of Bias evaluation for PM2.5 related to Lab. Z

Figure 127: Chart of Bias evaluation for PM2.5 related to Lab. AD

¹ In the 2015 report ‘Evaluation of the Field Comparison Exercise for PM10 and PM2.5, Ispra, February 13th – April 9th, 2015’, as σpt the standard deviation of participants results was taken and u(xpt) was calculated without homogeneity – contribution.