Report No. 2001/2 Working Group "Firearms" of the European Network of Forensic Science Institutes GSR2001 Proficiency Test Report on the 3 rd European Proficiency Test on Identification of GSR by SEM/EDX Co-financed by the OISIN-Program of the European Union page 1 of 8
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Report No. 2001/2
Working Group "Firearms" of the European Network of Forensic Science Institutes
GSR2001 Proficiency Test
Report on the
3rd European Proficiency Test on Identification of GSR by SEM/EDX
Co-financed by the OISIN-Program
of the European Union
page 1 of 8
Report No. 2001/2
Operation & Administration
Bundeskriminalamt KT23 D-65173 Wiesbaden Phone: +49-611-551-2678 Fax: +49-611-551-3263 Email: [email protected]
Organisation Panel
Dr. Jan Andrasko National Laboratory of Forensic Science, SKL Sweden Reggie Beijer Netherlands Forensic Institute, NFI Netherlands Lawrence Gunaratnam National Bureau of Investigation, NBI Finland Dr. Ludwig Niewöhner Bundeskriminalamt, BKA Germany
Remark on Confidentiality
This report and also all results affecting the GSR2001 proficiency test have to be treated as confidential unless they are presented and discussed in the annual meeting of the ENFSI working group "Firearms" and/or published by the Organisation Panel. This particularly means that any publication or forwarding of data, even in excerpts, concerning the results of the proficiency test have to be authorised by the Organisation Panel.
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Report No. 2001/2
INTRODUCTION Within the framework of the ENFSI Working Group "Firearms" a proficiency test on the detection
and identification of GSR by SEM/EDX was set up and performed. The test material was
designed by the Organisation Panel and manufactured by the company PLANO GmbH in
Wetzlar, Germany. The participating laboratories were requested to determine the total number of
PbSbBa containing particles on the test samples following their own laboratory specific methods
of automated GSR particle search and detection by SEM/EDX. Two almost similar samples were
dispatched to all participating laboratories in order to gain additional information on systematic
errors within the obtained results (split-level study). The two samples (sample SPS-A and sample
SPS-B) differentiate slightly in the number of PbSbBa particles, whereas one sample was
additionally provided with some environmental particles.
This report summarises the result of the study and gives information on the repeatabilities and
reproducibilities.
1. TEST MATERIALS
1.1. Preparation The test items for the GSR2001 proficiency test consisted of a set of specially prepared, identical
samples in accordance with the ISO 5725 for the performance of proficiency tests /1/. For each of
these samples a total number of 43 ‘synthetic GSR particles’ with the composition of PbSbBa
were precipitated onto a silicon substrate (size 8x8 mm²). The total number of PbSbBa particles
on the surface of the silicon substrate may be higher (so-called etch-resist particles), but due to
the production process the number of ’regular’ PbSbBa particles at known locations is fixed to 43.
The total number of deposited PbSbBa particles, their size and their location on the sample were
well defined. Finally the samples were coated with a thin photo resist layer to avoid mechanical
damage. Half of the samples were additionally provided with environmental particles of Pb, Fe
and Cu (contaminated samples; SPS-B). Table 1 summarises the information on the test
materials used for the study.
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Report No. 2001/2
Table 1: Number of regular particles deposited on the different samples used in this study
(the extension -X describes different layouts for sample SPS-A and SPS-B)
number of PbSbBa particles with a diameter of sample description
total number of PbSbBa particles 5 µm 2 µm 1 µm
SPS A521-1 (clean)
43 3 22 18
SPS A521-2 (clean)
43 3 22 18
SPS B521-1 (contaminated)
43 3 15 25
SPS B521-3 (contaminated)
43 3 15 25
1.2. Homogeneity and Stability A test of homogeneity was carried out at the Bundeskriminalamt, Wiesbaden controlling the
number of PbSbBa particles on a random selection of about 70% of the test samples. Most of the
controlled samples were proved to have a total number of 43 PbSbBa particles, whereas 11% of
the samples showed a deficit of one particle. It was decided that the test material was sufficiently
homogeneous for the intended use (43 [-1] particles [-2%]).
The prepared test samples were proved to be stable for a long period of time.
2. INTERLABORATORY STUDY
2.1. Organisation The distribution of the test samples to the participating laboratories and the data evaluation were
carried out by the Bundeskriminalamt. Table 2 shows the time schedule of the study. The
participating laboratories are listed in Appendix 1. A sample set of two samples (SPS-A and
SPS-B) was sent to 48 laboratories together with a sample description and some remarks on the
performance of the analytical investigation, two data report sheets and a questionnaire on the
analytical equipment used in the study (see Appendix 2). The Bundeskriminalamt received
analytical results from 43 laboratories within the pre-set time frame, whereas three laboratories
submitted two independent results from different SEM/EDX systems. Four laboratories had to be
excluded because of delayed data submission, and two laboratories submitted insufficient data.
Altogether 44 data-sets from 41 laboratories were considered in the statistical evaluation of the
study.
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Report No. 2001/2
Table 2: Time schedule of the study for the determination of GSR by SEM/EDX
Date Action May 2001 Announcement of the proficiency test by the ENFSI Working
Group "Firearms"; Call for statement of participation
29.08.2001 Distribution of the samples to the participants 22.09.2001 Deadline for submission of analytical results 03.12.2001 Dispatch of individual results Dec. 2001 Statistical evaluation of results; preparation of final report Jan. 2002 Dispatch of final report
2.2. Analytical Procedures The participants were requested to carry out a particle search according to their standard
parameter settings for automated GSR search by SEM/EDX for each of the two samples. At least
7x7 mm² of the silicon chip area had to be searched for particles, and the XY co-ordinates and
the sizes of the detected PbSbBa particles had to be reported. For the samples SPS-B,
additionally the number of detected Pb, Cu and Fe particles had to be reported (see Appendix 2).
2.3. Data Assessment Before starting the statistical evaluation, multiply counted particles and PbSbBa particles
detected on non-regular locations (etch-resist) had to be subtracted from the submitted raw data.
Only the detected ‘regular’ PbSbBa particles were considered in the evaluation. The data
assessment followed the ISO 5725-2 protocol implemented in the software package ProLab2000
/2/, which is widely used for the evaluation of laboratory proficiency tests. Table 3 shows the
different steps of the assessment. The corrected data of all participants are summarised in
Appendix 3. Furthermore Appendix 3 shows the histogram plots of the achieved values for three
investigated characteristics.
Table 3: Data assessment for the evaluation of the GSR determination study
Step Laboratory Coding of the participating laboratories Lab-ID #001 to #062 Coding of the available sample materials (SPS-A and SPS-B) sample-ID #001 to #120 Correction of the received data Creation of an Excel spread-sheet of all data (raw and corrected) Twofold comparison of the created database with the original data Import of the data into the software package ProLab2000 for statistical evaluation
Evaluation of the data according to ISO 5725-2
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Report No. 2001/2
A test of outliers was neglected because robust statistics was applied for the statistical
assessment of the received data /3, 4/.
The mean value (Xtotal) for the total number of PbSbBa particles was calculated from the test of
homogeneity (ref. chapter 1.2) to 42.9 particles and rounded up to the ‘true value’ of 43. The
standard deviation (σtotal) was empirically determined based on the achieved valid data. Similar
assumptions were made for the values of detected 1µm and 2µm particles. The values for all
sample / characteristic combinations used for the calculation of the z-scores are shown in
Table 4.
Table 4: Mean values and standard deviations for the different characteristics and samples
SPS-A SPS-B meas. characteristics
mean std. dev. mean std. dev. no of det. PbSbBa particles (TOTAL) 43 2.302 43 2.966
no of det. PbSbBa particles (2 µm) 22 0.869 15 0.622
no of det. PbSbBa particles (1 µm) 18 1.173 25 1.824
2.4. Laboratory Evaluation An evaluation of the laboratory’s proficiency to detect GSR particles by SEM/EDX was carried out
using z-scores according to IUPAC and EURACHEM /5, 6, 7/. The z-scores were calculated
using standard deviation and mean as shown in Table 4. The z-scores of all laboratories are
given in Appendix 4. For the final assessment of the received results in the study the z-scores for
both samples had to fulfil the criteria for the different characteristics at once. Regarding the
characteristic total number of detected PbSbBa particles, 27 out of 44 laboratories obtained
satisfactory z-scores (|z| < 2) for both investigated samples, whereas the results of 7 laboratories
are considered as ‘questionable’ (2 ≤ |z| ≤ 3). Ten laboratories were considered to have obtained
unsatisfactory results (|z| > 3). For these 10 laboratories it can be stated with a certainty of at
least 95% that the assessment is correct. The obtained values for all three characteristics are
given in Table 5.
Additionally, the intra-laboratory reproducibility of the participating laboratories was determined by
the graphical presentation of the results of both samples (SPS-A and SPS-B) in a Youden plot /8,
9/ (see Appendix 5). These plots give an impression of the repeatability and reproducibility of a
particular laboratory and allows an estimation of systematic errors as well. A laboratory which can
be found within the red square is supposed to have a satisfying reproducibility, whereas a
laboratory within the blue square shows questionable reproducibility. A laboratory lying outside
the blue square is not performing reproducible results with its system and should optimise its
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Report No. 2001/2
parameter settings. Another aspect is the laboratory’s distance to the 45° line. Laboratories close
to this line are indicative to have a good repeatability within their measurements, no matter if they
can be found within or outside the red/blue square. In contrary to this, the further laboratories are
lying away from this line, the worse their repeatability is. This distance gives conclusions of the
systematic errors within the laboratory.
Similar evaluations were performed for the characteristics number of detected 1µm particles and
number of detected 2µm particles, respectively.
Table 5: Overall proficiency values for the 3 characteristics (both samples considered)
Satisfactory (|z| < 2)
Questionable
(2 ≤ |z| ≤ 3)
Unsatisfactory (z > |3|)
TOTAL 27 (61%) 7 (16%) 10 (23%)
1 µm 24 (55%) 6 (14%) 14 (32%)
2 µm 24 (55%) 8 (18%) 12 (27%)
The results show a good overall performance of the participating laboratories. More than 60% of
the laboratories meet the proficiency criteria for the characteristic total number of detected
PbSbBa particles when using their own laboratory procedure and parameter settings for the
detection and identification of GSR. Individual results can be looked up in Appendix 4.
3. ACKNOWLEDGEMENT The Organisation Panel thanks the European Union and the Bundeskriminalamt for financial
support of the study (EU-Project No. JHA/OISIN/012).
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Report No. 2001/2
References
/1/ ISO 5725-1994 (E), Part. 1 to 6; "Accuracy (Trueness and Precision) of Measurement
Methods and Results".
/2/ ProLab2000; quo data GmbH; Dresden; Germany.
/3/ Huber, P.J.; "Robust statistics"; John Wiley & Sons (1981); New York.
/4/ Rousseeuw, P.J.; "Tutorial to Robust Statistics"; Journal of Chemometrics; 5 (1991);
p.1-20.
/5/ ISO 43-1995 (E); "Part.2: Development and Operation of Proficiency Testing Programs".
/6/ Thomson M., Wood R.; "The International Harmonized Protocol for the Proficiency Testing
of (Chemical) Analytical Laboratories, (Technical Report)"; Pure Appl. Chem.; 65 (1993);
p. 2123-2144.
/7/ EURACHEM Guide on "Selection, Use and Interpretation of Proficiency Testing (PT)
Schemes by Laboratories"; edition 1.0-2000; Internet: www.eurachem.bam.de .
/8/ Tholen, D.W.; "Statistical Treatment of Proficiency Testing Data"; Accred. Qual. Assur.; 3
(1998); p. 362-366.
/9/ Youden, W.J.; "Statistical Techniques for Collaborative Tests"; publ. in: "Statistical Manual
of the AOAC"; AOAC International (1975); Gaithersburg.
Appendices
1. list of all participating laboratories
2. instructions and data sheet for the 3rd ENFSI Proficiency Test on GSR by SEM/EDX
3. list of corrected data and histogram plots
4. z-scores of all participating laboratories for the 3 evaluated characteristics
5. Youden plot of all participating laboratories for the 3 evaluated characteristics
page 8 of 8
Appendix 1 List of all participating laboratories
Laboratory Country 1 Alameda G. Sheriff's Office Crime Lab U.S.A 2 Bayerisches Landeskriminalamt Germany 3 Bundeskriminalamt Germany 4 Bundesministerium für Inneres der Republik Österreich
Kriminaltechnische Zentralstelle Austria
5 Central Forensic Laboratory of the Polish Police Chemistry Department
Poland
6 Centre of Forensic Sciences Canada 7 Centro de Investigación y Criminalística
Direccion General de la Guardia Civil Spain
8 Comisaría General de Policía Científica Laboratorio Químico
Spain
9 Contra Costa Crime Lab U.S.A 10 Danish Technical Institute Danmark 11 ESF Environmental Chemistry, Science & Forestry U.S.A 12 Forensic Institute Bratislava
Dept. of Chemistry Slovakia
13 Forensic Science Laboratory, Garda HQ Ireland 14 Forensic Science Northern Ireland Northern Ireland 15 Forensic Science Service
Birmingham Laboratory England
16 Hamilton County Coroner's Lab Chief of Forensic Sciences
U.S.A
17 Hessisches Landeskriminalamt Germany 18 Honolulu Police Dept.
Scientific Investigation Section U.S.A
19 I.R.C.G.N.; Département Microanalyse France 20 Illinois State Police
Forensic Science Center at Chicago U.S.A
21 Institute of Criminalistics Prague Czech Republic 22 Institute of Forensic Research
Department of Criminalistics Poland
23 Toolmarks and Materials Laboratory Div. of Identification and Forensic Science (DIFS)
Israel
24 Laboratorio de Policia Cientifica Policia Judiciaria
Portugal
25 Landeskriminalamt Baden-Württemberg Germany 26 Landeskriminalamt Brandenburg Germany 27 Landeskriminalamt Hamburg Germany 28 Landeskriminalamt Mecklenburg-Vorpommern Germany 29 Landeskriminalamt Niedersachsen Germany 30 Landeskriminalamt Nordrhein-Westfalen Germany 31 Landeskriminalamt Sachsen Germany 32 Landeskriminalamt Sachsen-Anhalt Germany 33 Landeskriminalamt Schleswig-Holstein Germany 34 Landeskriminalamt Thüringen Germany 35 Ministerio de Justicia
Instituto Nacional de Toxicología Spain
36 Ministry of Interior Forensic Institute Laboratory for SEM
Croatia
37 Ministry of the Interior Republic of Slovenia 38 National Bureau of Investigation (NBI) Finland 39 National Criminal Investigation Service
Laboratory Division Norway
40 National Laboratory of Forensic Science (SKL) Department of Chemistry and Technology
Sweden
41 Netherlands Forensic Science Institute The Netherlands 42 NICC; Chemical Ballistics Unit Belgium 43 Orange County Sheriff's Department
Forensic Science Services U.S.A
44 Orange County Sheriff's Department Forensic Science Services
U.S.A
45 Physikalisch-Technische Untersuchungstelle Berlin Germany 46 Reparto Carabinieri Investigazioni Scientifiche Italien 47 Royal Canadian Mounted Police
Forensic Laboratory Services - Ottawa Canada
48 West Virginia State Police Forensic Laboratory
U.S.A
Appendix 2 B u n d e s k r i m i n a l a m t - K T 2 3 * D - 6 5 1 7 3 W i e s b a d e n Wiesbaden, 28-Sept.-2001
address of participating laboratory
ENFSI Proficiency Test on Identification of GSR by SEM/EDX (GSR2001)
(European Union Project No. JHA/OISIN/012) Dear colleagues, enclosed are your samples for the ENFSI Proficiency Test on GSR (GSR2001). Please examine them, as far as feasible, according to your standard laboratory procedure for GSR analysis. The proceeding of the ENFSI Proficiency Test GSR2001 will be performed in the same way as in the previous tests. Lab-IDs have been assigned to all participating laboratories in order to maintain confidentiality. After the evaluation of the test each laboratory will be informed immediately about its findings in an individual report. The results compiled from this program will be published in a final report and presented for discussion at the next meeting of the ENFSI firearms working group. The ENFSI Proficiency Test GSR2001 consists of a set of synthetic samples which are identical in a specific way. That means there is a certain amount of synthetic GSR particles – this time consisting of Pb, Sb and Ba – on each sample with well-defined size and location. The composition of the particles as well as their location and size are exactly known by the organiser. All participants are requested to search for Lead/Antimony/Barium/(Si) particles (Silicon due to the silicon substrate) on the test samples instead of unique GSR particles.
Appendix 2 Instructions You will find enclosed the sample set of the ENFSI Proficiency Test GSR2001, assigned with a specific sample ID on the plastic container. If somehow possible please examine the samples according to your default SEM/EDX settings. If there is a change of parameter settings necessary to run the samples, please note that in the comments. The samples show the following properties: A Silicon chip of 8x8 mm² is mounted on a standard 1/2-inch stub. On this chip there is an area of 7x7 mm² where an exactly defined number of PbSbBa particles is distributed. (In fact the composition of the "GSR particles" is Pb, Sb, Ba, Si and F. Due to technical reasons there is always a Si-signal in the EDX-spectrum because of the silicon substrate. The F-signal results from the metal fluoride that was used in the sample preparation process.) The PbSbBa particles have to be searched and filed. For protective reasons the chip is finally coated with a thin carbon layer, therefore a carbon coating of the sample is not recommended. On one of the delivered samples, this protective layer is deliberately provided with some small particles of pure Iron, Copper and Lead in order to give them a more realistic impression. The second sample is free of such "contamination" for reasons of a standard for fast validation purposes in a future application. Mount the test sample on your stage in a way that the small 100x100 µm² pad is displayed in the lower left corner of your SEM screen, and examine at least the centre area of 7x7mm² of the chip (see Figure 1).
100 x 100 µm² padPbSbBa
If the BSE threshold adjustment has to be changed compared to your standard settings (because of the Silicon substrate) it is recommended to use the 100x100µm² pad or the 5µm PbSbBa particle, which is located exactly in the centre of the chip (4000;4000), for a suitable BSE adjustment. If a high Si-signal in the obtained spectra is leading to a false classification of the PbSbBa particles, it is suggested to either add Silicon as a matrix element in your criteria list or set the Si-signal to zero. Alternatively you may reduce the accelerating voltage down to 20 kV. Please note any of these necessary changes of the standard settings as a comment in your data report sheets.
Figure 1:BSE image of the lower left corner part of the test sample; EDX spectrum of Pb/Sb/Ba pad
Appendix 2 Data Reporting Record your results together with your lab-ID and the corresponding sample IDs in a data sheet as shown in Appendix A1 and A2. Required are the absolute X and Y co-ordinates (in µm or mm) and the particle size (calculated diameter) of the detected PbSbBa particles. In particular OXFORD ISIS and LINK eXL users are requested to report the XY-stage point co-ordinates and the beam point co-ordinates of the detected PbSbBa particles as well as the width and height of the electrical search fields. Additionally all participants are requested to report the number of detected Pb, Cu and Fe particles, the searched area and the total analysis time . It is demanded to record the data also electronically (as an EXCEL-file or as a *.txt file, tab separated), and send them on disk and/or by e-mail to the organiser. Finally, you are asked to fill in Appendix B to document the instrumental/procedural conditions of your search. Deadline Results that are labelled with your lab-ID and sample-IDs must be received (at least in electronic form) by the organiser before 22nd October 2001 in order to be evaluated and considered in the final report. Furthermore it is referred to the "Statement for subscription and conditions for participation" in the letter of intent from 30th April 2001. Lab-ID
Your lab-ID is: __________
Appendix 2 APPENDIX A1 Lab-ID:___________ (clean sample)
Sample ID:________ analytical data total analysis time: __________ [min] total area of search: __________ [mm²] size of mechanical field: __________ [µm] x __________ [µm] size of electrical field: __________ [µm] x __________ [µm] no. of detected PbSbBa particles: __________ location of the detected PbSbBa particles: Exemplary table for the detected PbSbBa-particles (OXFORD ISIS and LINK eXL users: report also XY-stage point and XY beam point co-ordinates)
no. size [µm] Xabs [µm] or [mm] Yabs [µm] or [mm] 1 5 4000 40002 3 4 5 6
--- --- --- 74 75
Please expand in case of need It is demanded to send the data also on disk and/or by e-mail (as an EXCEL-file or as a *.txt file, tab separated, and labelled with your lab-ID). comments ______________________________________________________________________________________________________________________________________________________________________________________________________________________________
Appendix 2 APPENDIX A2 Lab-ID:___________ (contaminated sample)
Sample ID:________ analytical data total analysis time: __________ [min] total area of search: __________ [mm²] size of mechanical field: __________ [µm] x __________ [µm] size of electrical field: __________ [µm] x __________ [µm] no. of detected PbSbBa particles: __________ no. of detected Pb particles: __________ no. of detected Cu particles: __________ no. of detected Fe particles: __________ location of the detected PbSbBa particles: Exemplary table for the detected PbSbBa-particles (OXFORD ISIS and LINK eXL users: report also XY-stage point and XY beam point co-ordinates)
no. size [µm] Xabs [µm] or [mm] Yabs [µm] or [mm] 1 5 4000 40002 3 4
--- --- 74 75
Please expand in case of need It is demanded to send the data also on disk and/or by e-mail (as an EXCEL-file or as a *.txt file, tab separated, and labelled with your lab-ID). comments ____________________________________________________________________________________________________________________________________________________
Appendix 2 APPENDIX B Lab-ID:_____________ Analytical Equipment SEM -Type :_______________________ Year of Purchase: _______________ EDX -System :_______________________ Year of Purchase: _______________ Analyser :_______________________ Year of Purchase: _______________
BSE-Detector Manual Digital Type & Model: ______________________ Year of Purchase: _______________ Kind of Standard for Calibration: _________________________________________
GSR - Search By Software: Manually Software Name:_______________________ Year of Purchase: _______________ Acquisition-Parameters Accelerating Voltage :__________________________(kV) Probe Current :__________________________(nA) Search Magnification :__________________________(X) Size of electrical field (BSE search) :__________________________(µm x µm) Minimum Size of Particles detected :__________________________(µm) Maximum Size of Particles detected :__________________________(µm) Minimum Total Counts per Particle :__________________________(cps) Normal X-ray Acquisition Time :__________________________(s) Maximum X-ray Acquisition Time :__________________________(s) Particle Relocation After the automatic Search: Manually By Software After the stubs have been removed and returned into the system: Yes No If YES:
By Software using Reference Markers Manually
Appendix 3 sample SPS-A sample SPS-B Lab-ID# TOTAL 2 µm 1 µm TOTAL 2 µm 1 µm [particle] [particle] [particle] [particle] [particle] [particle] 001 43 22 18 40 15 22 002A 42 22 17 43 15 25 002B 43 22 18 43 15 25 003 41 21 18 43 15 25 004 43 22 18 43 15 25 005 no results submitted within deadline no results submitted within deadline 006 43 22 18 43 15 25 007 41 21 18 41 15 23 008 40 20 17 43 15 25 009A 43 22 18 43 15 25 009B 43 22 18 43 15 25 010 39 22 14 39 14 22 011 37 20 14 32 15 14 012A 43 22 18 43 15 25 012B 42 22 17 42 15 24 013 42 21 18 41 15 23 014 43 22 18 43 15 25 020 0 0 0 1 0 0 021 43 22 18 43 15 25 022 32 18 11 26 9 15 023 32 19 10 34 13 18 024 submitted results not evaluable submitted results not evaluable 025 43 22 18 31 13 15 026 36 20 14 35 13 21 027 43 22 18 43 15 25 028 38 21 16 39 13 24 029 22 15 6 20 10 7 030 no results submitted within deadline no results submitted within deadline 031 38 19 16 41 15 24 032 no results submitted within deadline no results submitted within deadline 033 no results submitted within deadline no results submitted within deadline 034 43 22 18 43 15 25 035 32 16 14 35 11 22 036 41 21 17 39 15 21 037 38 19 16 submitted results not evaluable 038 31 16 12 39 14 22 039 42 21 18 42 14 25 040 42 22 17 42 15 24 041 43 22 18 43 15 25 050 22 14 5 30 9 19 051 36 19 15 38 13 22 052 43 22 18 36 12 21 053 42 22 17 43 15 25 054 37 19 15 38 13 22 055 41 20 18 40 14 23 056 no participation no participation 057 39 20 17 36 12 21 058 43 22 18 42 15 24 059 41 22 16 40 13 24 060 43 22 18 43 15 25 061 no results submitted within deadline no results submitted within deadline 062 40 22 15 38 13 22
Appendix 3 Received 'raw data'
Overview: Total Number of Detected PbBaSb-Particles = f(LabID)
0
15
30
45
60
75
90
#001
#002
(SEM
1)#0
02 (S
EM2)
#003
#004
#006
#007
#008
#009
(SEM
1)#0
09 (S
EM2)
#010
#011
#012
(SEM
1)#0
12 (S
EM2)
#013
#014
#020
#021
#022
#023
#025
#026
#027
#028
#029
#031
#034
#035
#036
#037
#038
#039
#040
#041
#050
#051
#052
#053
#054
#055
#057
#058
#059
#060
#062
LabID#
Det
ecte
d Pb
BaSb
Par
ticle
s
Clean Sample
Contaminated Sample
Corrected data ('regular' particles):
Overview: "Corrected" Number of Detected PbBaSb-Particles = f(LabID)
0
5
10
15
20
25
30
35
40
45
50
55
#001
#002
(SEM
1)#0
02 (S
EM2)
#003
#004
#006
#007
#008
#009
(SEM
1)#0
09 (S
EM2)
#010
#011
#012
(SEM
1)#0
12 (S
EM2)
#013
#014
#020
#021
#022
#023
#025
#026
#027
#028
#029
#031
#034
#035
#036
#037
#038
#039
#040
#041
#050
#051
#052
#053
#054
#055
#057
#058
#059
#060
#062
LabID#
Det
ecte
d Pb
BaSb
Par
ticle
s
Clean Sample
Contaminated Sample
43 particles (both samples)
Appendix 3 Histogram plot of detected particles (sample SPS-A):
Overview: "Corrected" Number of Detected PbBaSb-Particles vs. No. of Lab
0
5
10
15
20
25
30
35
40
45
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
No. of Lab
Det
ecte
d Pb
BaS
b Pa
rtic
les
Clean Sample
Histogram plot of detected particles (sample SPS-B):
O verview : "C orrec ted " N um ber o f D e tec ted PbBaSb-Partic les vs. N o . o f Lab
0
5
10
15
20
25
30
35
40
45
50
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
N o. o f Lab
Det
ecte
d Pb
BaS
b Pa
rtic
les
C ontam inated S am ple
Appendix 3 Obtained results versus EDX systems:
EDX Systems
0
5
10
15
20
25
30
35
40
45
50
No. of Lab
Amou
nt o
f Det
ecte
d Pb
SbBa
Par
ticle
s
Clean Sample
Contaminated Sample
EDAX EDITOR exL II ISIS300 PSEM
remark: a PGT, Noran and Kevex system was used only in one laboratory Cluster frequency plot for both samples (width of interval: 5 particles):
Cluster Frequencies of the Lab Results
0
5
10
15
20
25
30
0-5 6-10 11-15 16-20 21-25 26-30 31-35 36-40 41-43
Cluster [Amount of Particles]
Amou
nt o
f Lab
orat
orie
s
Clean SampleContaminated Sample
Appendix 4
z-scores TOTAL 2 µm 1 µm
Lab-ID#
SPS-A SPS-B SPS-A SPS-B SPS-A SPS-B 001 0,0 -1,0 0,0 0,0 0,0 -1,6 002A -0,4 0,0 0,0 0,0 -0,9 0,0 002B 0,0 0,0 0,0 0,0 0,0 0,0 003 -0,9 0,0 -1,2 0,0 0,0 0,0 004 0,0 0,0 0,0 0,0 0,0 0,0 005 -- -- -- -- -- -- 006 0,0 0,0 0,0 0,0 0,0 0,0 007 -0,9 -0,7 -1,2 0,0 0,0 -1,1 008 -1,3 0,0 -2,3 0,0 -0,9 0,0 009A 0,0 0,0 0,0 0,0 0,0 0,0 009B 0,0 0,0 0,0 0,0 0,0 0,0 010 -1,7 -1,3 0,0 -1,6 -3,4 -1,6 011 -2,6 -3,7 -2,3 0,0 -3,4 -6,0 012A 0,0 0,0 0,0 0,0 0,0 0,0 012B -0,4 -0,3 0,0 0,0 -0,9 -0,5 013 -0,4 -0,7 -1,2 0,0 0,0 -1,1 014 0,0 0,0 0,0 0,0 0,0 0,0 020 -18,7 -14,2 -25,3 -24,1 -15,3 -13,7 021 0,0 0,0 0,0 0,0 0,0 0,0 022 -4,8 -5,7 -4,6 -9,6 -6,0 -5,5 023 -4,8 -3,0 -3,5 -3,2 -6,8 -3,8 024 -- -- -- -- -- -- 025 0,0 -4,0 0,0 -3,2 0,0 -5,5 026 -3,0 -2,7 -2,3 -3,2 -3,4 -2,2 027 0,0 0,0 0,0 0,0 0,0 0,0 028 -2,2 -1,3 -1,2 -3,2 -1,7 -0,5 029 -9,1 -7,8 -8,1 -8,0 -10,2 -9,9 030 -- -- -- -- -- -- 031 -2,2 -0,7 -3,5 0,0 -1,7 -0,5 032 -- -- -- -- -- -- 033 -- -- -- -- -- -- 034 0,0 0,0 0,0 0,0 0,0 0,0 035 -4,8 -2,7 -6,9 -6,4 -3,4 -1,6 036 -0,9 -1,3 -1,2 0,0 -0,9 -2,2 037 -- -- -- -- -- -- 038 -5,2 -1,3 -6,9 -1,6 -5,1 -1,6 039 -0,4 -0,3 -1,2 -1,6 0,0 0,0 040 -0,4 -0,3 0,0 0,0 -0,9 -0,5 041 0,0 0,0 0,0 0,0 0,0 0,0 050 -9,1 -4,4 -9,2 -9,6 -11,1 -3,3 051 -3,0 -1,7 -3,5 -3,2 -2,6 -1,6 052 0,0 -2,4 0,0 -4,8 0,0 -2,2 053 -0,4 0,0 0,0 0,0 -0,9 0,0 054 -2,6 -1,7 -3,5 -3,2 -2,6 -1,6 055 -0,9 -1,0 -2,3 -1,6 0,0 -1,1 056 -- -- -- -- -- -- 057 -1,7 -2,4 -2,3 -4,8 -0,9 -2,2 058 0,0 -0,3 0,0 0,0 0,0 -0,5 059 -0,9 -1,0 0,0 -3,2 -1,7 -0,5 060 0,0 0,0 0,0 0,0 0,0 0,0 061 -- -- -- -- -- -- 062 -1,3 -1,7 0,0 -3,2 -2,6 -1,6
Appendix 4
-5
-4
-3
-2
-1
0
1 2A 2B 3 4 6 7 8 9A 9B 10 11 12A
12B 13 14 20 21 22 23 25 26 27 28 29 31 34 35 36 38 39 40 41 50 51 52 53 54 55 57 58 59 60 62
Lab-ID#
z-sc
ores
TOTAL SPS_ATOTAL SPS_B
-5
-4
-3
-2
-1
0
1 2A 2B 3 4 6 7 8 9A 9B 10 11 12A
12B 13 14 20 21 22 23 25 26 27 28 29 31 34 35 36 38 39 40 41 50 51 52 53 54 55 57 58 59 60 62
Lab-ID#
z-sc
ores
2µm SPS_A2µm SPS_B
-5
-4
-3
-2
-1
0
1 2A 2B 3 4 6 7 8 9A 9B 10 11 12A
12B 13 14 20 21 22 23 25 26 27 28 29 31 34 35 36 38 39 40 41 50 51 52 53 54 55 57 58 59 60 62
Lab-ID#
z-sc
ores
1µm SPS_A1µm SPS_B
Appendix 5 Characteristic: Total number of detected PbSbBa particles
-9,0
-8,0
-7,0
-6,0
-5,0
-4,0
-3,0
-2,0
-1,0
0,0
1,0
2,0
-9,0 -8,0 -7,0 -6,0 -5,0 -4,0 -3,0 -2,0 -1,0 0,0 1,0 2,0
Z-Scores SPS-A
Z-Sc
ores
SPS
-B
# 052
# 025# 011
# 057
# 026
# 051 # 054# 038
# 035
# 023
# 022
# 050
# 029
# 020
Youden Plot for the Presentation of inter-laboratory Precision
Total Number of GSR Particles
Characteristic: number of detected 1 µm particles
-9,0
-8,0
-7,0
-6,0
-5,0
-4,0
-3,0
-2,0
-1,0
0,0
1,0
2,0
-9,0 -8,0 -7,0 -6,0 -5,0 -4,0 -3,0 -2,0 -1,0 0,0 1,0 2,0
Z-Scores SPS-A
Z-Sc
ores
SPS
-B
# 052# 036# 057
# 051# 054# 062
# 010# 035
# 026
# 025
# 023
# 038
# 020
# 011
# 022
# 050
# 029
Youden Plot for the Presentation of inter-laboratory Precision
Number of 1µm Particles
Appendix 5 Characteristic: number of detected 2 µm particles
-9,0
-8,0
-7,0
-6,0
-5,0
-4,0
-3,0
-2,0
-1,0
0,0
1,0
2,0
-9,0 -8,0 -7,0 -6,0 -5,0 -4,0 -3,0 -2,0 -1,0 0,0 1,0 2,0
Z-Scores SPS-A
Z-Sc
ores
SPS
-B
# 052# 057
# 023# 051# 054
# 031
# 038
# 035
# 022
# 029
# 050
# 020
Youden Plot for the Presentation of inter-laboratory Precision
Number of 2µm Particles
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