HESSISCHES LANDESAMT FÜR UMWELT UND GEOLOGIE (HESSIAN STATE OFFICE FOR ENVIRONMENT AND GEOLOGY) - Kassel Office -

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1 Page 1 of 11 Specifications for interlaboratory testing of sites in accordance with 26 BImSchG (Federal Immission Control Act) (fine particles and fine particles-content emission components) Status June General 1.1 Aim of testing and basis The aim of the interlaboratory tests is a quality control of sites that, in accordance with 26 BImSchG, have been designated to investigate fine particles, fine particles content and chemical compounds attached to the fine particles. The basis for the testing specifications is the "Report on the testing and, where necessary, re-setting of precision specifications and the inclusion of chromium in the evaluation for interlaboratory tests with particulate emission components using the Emission Simulation Facility (ESA) for quality assurance of emissions measurements" Organizer The organizer is the HESSISCHE LANDESAMT FÜR UMWELT UND GEOLOGIE (HLUG) (HESSIAN STATE in Kassel, on behalf of state authorities legally responsible for the designation. 2 Testing 2.1 Frequency, place and duration A request to the sites designated for the corresponding areas [A] and [I] is made once every three years or within the designation limit of 5 years. In the case of sites with different locations the request to participate in an interlaboratory test can be issued several times within the 5-year period in order to include the relevant locations in an appropriate way. Place of the interlaboratory test is: HESSISCHE LANDESAMT FÜR UMWELT UND GEOLOGIE (HLUG) Ludwig-Mond-Str Kassel Tel.: 0561/ Fax: 0561/ emission@hlug.de Contact persons: Herr Edgar Vogel: Tel.: -141 The interlaboratory test lasts for two days; details such as the exact sequence will be sent with the request to participate. 1 Source:

2 Page 2 of Request to participate and dates The state authorities legally responsible for the designation can delegate the request to participate in the interlaboratory test to the HLUG. The request to participate is then issued by the HLUG at random on the basis of the current version of the "Recherchesystem Messstellen und Sachverständige" (RESYMESA) (Research system measuring sites and experts). Moreover, sites can be named for the HLUG for a particular reason (e.g. repeat or sites which the state authorities legally responsible for the designation think should be tested). The percentage of participants chosen at random is to be less than 50%. The request to participate is usually issued three months, at the latest two months, before the interlaboratory test date. The participation is to be confirmed by the site on an enclosed reply form within 10 working days. Because participation in the interlaboratory test has a high priority, cancellation is accepted only if the reasons given are in line with the strictest standards. Any cancellation to participate must be accompanied by the written agreement of the state authorities legally responsible for the designation. Failure to reply to a request to participate will be evaluated as an inexcusable failure. 3. Measurements The objects of the interlaboratory tests are the investigation parameters fine particles concentration (total fine particles concentration) and heavy metal concentrations of Cd, Co, Cu, Ni, Pb and Cr. An extension of the contents is possible in principle. Every participant carries out the investigation of the fine particles load by means of isokinetic removal of a particulate partial volume in accordance with guideline VDI 2066, sheet 1, "Measurement of particles,, fine particles measurement in flowing gases, gravimetric determination of the fine particles load" (half-hour median values, HSMW) in the current version. For sample taking procedures that do not correspond to this norm an equivalence proof corresponding to the "Technical Specification CEN TS 14793" is to be produced. All components installed in the plane filter have to conform with the specifications of the VDI guideline The individual measurement lasts for a half hour. Ten individual measurements (3x3 fine particles samplings and an introductory measurement with fine particles dosing) are to be carried out. Before the start of the interlaboratory test the following marginal conditions are to be recorded: standard choice of measuring points Investigation of the velocity profile in section by measuring the dynamic and static pressure on two measurement axes; number of measurement points: 2 per axis air pressure at the height of the measurement level temperature in the measurement channel water vapour content in the measurement channel calculation of the exhaust gas volume

3 Page 3 of 11 The measurement results for the exhaust gas marginal conditions are to be handed in by the participant s ininterlaboratory tests as part of results communication. These data have a purely informal character. The interlaboratory test is carried out simultaneously by all participants. For the non-conforming application of the complete measurement procedure the interlaboratory test participants use exclusively facilities/equipment of their own. The overhaul of the plane filter and analysis of the fine particles content is carried out in the laboratories of the sites. Further details, especially the time sequence of the interlaboratory test, can be found in the "Bulletin for interlaboratory test participants on the course of the interlaboratory test for the Investigation of fine particles and fine particles contents using the Emission Simulation Facility (ESA). 3.1 Fine particles concentration offered Per interlaboratory test three concentration levels should be offered. The concentrations range as follows: level 1 1 to 4 mg/m 3 level 2 4 to 7 mg/m 3 level 3 7 to 12 mg/m Investigation and specification of results Three values are to be examined and handed in per concentration level and components by the interlaboratory test participants. The measurement results have to relate to normal conditions (273 K, 1013 hpa). For fine particles the specification has the dimension mg/m 3 and for heavy metals the dimension µg/m 3. Both results are specified with one decimal place each. The rounding of the results is done in accordance with no of DIN 1333 Bl. 2/1992. The results are sent by internet. Each participant receives a PIN code from the organizer, with which the input screen of the HLUG internet site can be activated. The PIN code is issued to the participants in the final meeting in a sealed envelope. The results have to be communicated to HLUG six weeks at the latest after the conclusion of the interlaboratory test. In addition to the heavy metal concentration in µg/m 3 there should also be a specification in contents data relating to fine particles mass in mg/mg. This specification is not evaluationrelevant, but in the case of defective fine particles sample-taking makes it possible to identify, if necessary, a correct analytical determination of the contents.

4 Page 4 of Evaluation of the interlaboratory test The evaluation is done according to the z-score procedure. Accordingly, a z-score value Z i as in equation (1) is calculated for each measurement and analysis result zi xi X (1) Captions: x i = individual measurement/analysis value of a concentration level X = estimated value for the true result (target value) s = precision specification The estimated value X for the true result of a fine particles concentration is calculated as a fixed specification from the index data of the facility (gravimetrically recorded dosing rate, measured ESA volume flow), taking an experimentally examined measurement uncertainty into account. The estimated values for the true results of the heavy metal concentrations are medians of the analysis data of comparison investigations of several reference laboratories (those of the state institutes and state offices). The precision specification is specified as quality assurance requirement. It amounts, depending on the target value, to: for the determination of the fine particles concentration: = 7 % for the determination of Cd: = 8 % for the determination of Co: = 8 % for the determination of Cu: = 8 % for the determination of Ni: = 8 % for the determination of Pb: = 8 % für die determination of Cr: = 12 % 4.1 Further evaluation For each individual measurement result of an i-ten participant a z-score is calculated as in equation (1) that has one decimal place more than the related result x i. For each concentration level the amounts of the three individual z-score values are combined to produce an arithmetic median value. This also represents the z-score value for the relevant concentration level.

5 Page 5 of Evaluation and designation of results 5.1 Evaluation By standardizing to the precision specification the following evaluation scheme for the z- score values is obtained: 2 result: satisfactory 2 3 result: questionable 3 result: unsatisfactory Basically, all participants who have achieved the z-score amounts > 2 are recommended to test their measuring procedure and/or analysis procedure. For the evaluation of the interlaboratory test each z-score value of a concentration level is assigned a class number: 2 class number class number 2 3 class number 3 For each investigation parameter with 3 concentration levels each: The sum of the class numbers may amount to a max.of 5, otherwise the determination of the investigation parameters is evaluated as "not successful". If only the results for two concentration levels in reasoned individual cases are available for an evaluation, the determination is to be evaluated as successful if the sum of class numbers amounts to 4 and the sum of the z-score values is 5,2. Similar to the amount designated "Investigation of fine particles, fine particles content and chemical compounds attached to fine particles", Investigation area [D], the results for the fine particles content are jointly evaluated. For the joint evaluation the following rule applies: For a successful participation in the area "Determination of fine particles contents" at least 5 of 6 heavy metals (Cd, Co, Cu, Ni, Pb and Cr) must have been successfully determined. (Success rate relating to the parameter number = 83 %) After testing of the interlaboratory test there are two parts of the results: - "Determination of fine particles" - "Determination fine particles contents", which are evaluated independently of each other.

6 Page 6 of 11 Failure to participate in the interlaboratory test without a good reason is evaluated as "unsuccessful participation". Interlaboratory test participants who have not been able to conclude the interlaboratory test "successfully" are invited to a repeat date. If it has not been possible to conclude the investigation of fine particles contents (heavy metals) successfully, the interlaboratory test participants receive relevant reference materials for post-analysis. In this case all the fine particles contents (heavy metals) relating to the interlaboratory test are to be analysed once again. The analysis results are to be communicated to HLUG. An evaluation will be made according to the above-mentioned scheme. 5.2 Communication of the results by HLUG The communication of the results to the interlaboratory test participants is done in the form of a total overview up to six weeks at the latest after the final date by which the participants have to hand in their results. A written copy of the results is also sent to the authorities legally responsible for the designation. The authorities legally responsible for the designation are requested to in form the appropriate accrediting agencies, in the case of accredited sites, about the result or to ensure that the site arranges for communication. The results of the certified standards handed over to the participants by the organizer make it possible for conclusions to be drawn about errors of any sort in the analytical evaluation of the participants. Points arising in this connection will be communicated in the results report. 6. Measures In the case of an "unsuccessful participation" in an interlaboratory test twice, it will be recommended to the authorities legally responsible for the designation to withdraw an appropriate designation ("Investigation of the emissions of fine particles, fine particles content and chemical compounds with adsorbed fine particles") from the relevant site for the areas concerned until a "successful participation" in an interlaboratory test is proved to he investigation parameters involved. The site is given the opportunity within a year. Failure to participate in the interlaboratory test without a good reason will be evaluated as "unsuccessful". 7. Objections and complaints Objections and complaints, if they are connected with the invitation, testing of the interlaboratory test, the communication of the results, are to be made to the aligner control unit of the interlaboratory test, HLUG, Ludwig-Mond-Str. 33, Kassel, Dezernat I 3, and if they relate to measures derived from the results (e.g. a request to repeat, repeal of the designation etc.), to the authorities legally responsible for the designation. The deadlines for objections are regulated in the appropriate notices/communications.

7 Page 7 of Costs The participant fee is levied in accordance with the relevant valid administration costs regulations for the business sector of the Hessisches Ministerium für Umwelt, Ländlichen Raum und Verbraucherschutz (Hessian Ministry of the Environment, Rural Areas and Consumer Protection). The current amount that corresponds to this will be named with the request to participate.

8 Page 8 of 11 Appendix Point 4 "Evaluation of the interlaboratory test": explanatory statement For the specification of the target value for the fine particles concentration from the characteristics of the dosing apparatus two main reason are to be mentioned: - Because of long-term experience with the operation of the facility and its optimization it is quite possible to calculate, from the difference weighting of the fine particles dosing piston and the measurement of the volume flow, the fine particles concentration with a precision of 5 %. The dosing is with a particle brush dosing feeder. The fine particles difference is investigated examined by weighing before and after the dosing. The exhaust column flow is determined by means of an integrated ring chamber orifice in accordance with the difference pressure procedure. The ring chamber orifice has been validated by comparison measurements. It is verified annually. Because of numerous fine particles concentration measurement in comparison with the calculated values from the dosing the calculated concentration has still to be multiplied with a correction factor in order to obtain the target value for the fine particles concentration. - Because of the number of participants who can take part simultaneously in an interlaboratory test is limited to a max. of four, the collective is too small to be able to derive the target value for the fine particles concentration using statistical methods from the participants' results. The same applies to investigating the target values for the fine particles content concentration. The specification of the target values for the heavy metal concentrations is investigated as follows: The fine particles employed for dosing are first homogenized using suitable procedures. The contents of the heavy metals to be analysed are identified before use with the cooperation of the state institutes and offices. Usually more than 10 laboratories take part in these analyses. The median of the results from the reference labs is used, by agreement, as the true value for the relevant heavy metal content. By multiplying the target values for the fine particles concentration with the relevant heavy metal content, the target value for the element concentration is calculated. The bases and data for specifying the target values for the interlaboratory testing are intelligibly documented by HLUG. In establishing the precision specification both for fine particles and heavy metals concentration investigation of the values from the results of participants in an interlaboratory test (max. 4 participants) is problematic if only because the requirement for each participant group depending on their results would change. A unified evaluation of all participants could not be guaranteed in this way. Furthermore, there would also be the problem, as in establishing the target value, of too small a collective for statistical evaluation. The precision requirement was investigated with a particular number of state investigating sites and sites in accordance with 26. The precision specifications were calculated from the relative deviations of the individual participants' results from the target value for the fine particles and the relevant heavy metal concentrations.

9 Page 9 of 11 With a total of 217 interlaboratory test participants providing the basis for the evaluation the max no. of deviations for fine particles and heavy metals per concentration level was 217 x 3 = 651. From this, taking outliers (Grubb's test) into consideration, it is possible to calculate a comparison standard deviation, from which the precision is calculated. For the individual investigation parameters and their concentration levels the following relative comparison standard deviations were obtained. Parameter Gesamtstaub Cadmium Kobalt Kupfer Nickel Blei Chrom * S Konz 1 [%] [Anzahl der Einzelwerte] S Konz 2 [%] [Anzahl der Einzelwerte] S Konz 3 [%] [Anzahl der Einzelwerte] 12, , , , , , , , , , , , , , , , , , , , , The values in the table show that there is no clear dependency of the relative comparison standard deviation from the concentration level (exceptions: Cr, Ni), the relative comparison standard deviations for the determination von Cd, Co, Cu, Ni and Pb are in the same order of size, the relative comparison standard deviation for the determination of Cr is clearly higher. The relative comparison standard deviations are combined via the concentration levels into a median value and considered separately for each component. The following averaged relative comparison standard deviations can be seen in the table: Parameter Gesamtstaub Cadmium Kobalt Kupfer Nickel Blei Chrom relative Vergleichsstandardabweichungen vom Sollwert [%] [Anzahl der Einzelwerte] 11, , , , , , ,

10 Page 10 of 11 A measurement within the limits of the target value comparison standard deviation is to receive the evaluation "satisfactory", which corresponds to z-score 2. The following connections can be derived from this: x X ij s zij ; from z 2 follows: s 2 The precision specifications first identified to evaluate interlaboratory tests with particlebound emissions components and documented in testing specifications of 1997 are summarized in the following list. The precisions calculated in 2007 on the basis of a clearly expanded data collective can be seen in the same list (bracket values). The slight deviations between the precisions investigated in 1997 and 2007 do not justify a change of the existing precisions. for the determination of the fine particles concentration: for the determination of Cd: for the determination of Co: for the determination of Cu: for the determination of Ni: for the determination of Pb: for the determination of Cr: = 7 (6) % of the target value = 8 (7) % of the target value = 8 (7) % of the target value = 8 (7) % of the target value = 8 (8) % of the target value = 8 (7) % of the target value = 12 (11) % of the target value On the basis that, with a precision specification for chromium of 12 %, a significant difference in the success rate compared with the other heavy metals cannot be detected, it seems justified to include chromium in the collective of the heavy metals to be drawn on for the evaluation. The precision specifications will also in future be tested regularly for their existing validity through continual input of the participants' results into a database. Explanation of point 5.1 "Evaluation" For the evaluation of the interlaboratory test a class number is assigned to each (averaged j from three individual z-score amounts) z-score value, which follows the basic evaluation scheme for z-scores: 2 class number 1 (result: satisfactory) 2 3 class number 2 (result: questionable) 3 class number 3 (result: unsatisfactory )

11 Page 11 of 11 In three concentration levels per interlaboratory test components the following are the combination possibilities for the class numbers of the three z-score values: Running no. of the combination Result of class membership Total of the classes Level 1 level 2 Level For the total result the sum of the three classes of each participant is evaluated in such a way that an "unsatisfactory" result (class number 3) can be offset by two "satisfactory" (each class number 1) (total class number 5); however, three "questionable" results (each class number 2, total 6) can no longer be evaluated as a "successful determination". If only the results for two concentration levels (6 measurement values) in justified individual cases are available for evaluation, the total of both z-score amounts of combination 3 in the above table should be ( = 7.8), i.e (7.8 * 2 / 3 = 5.2) The result is as follows: The determination is then to be evaluated as successfully if the sum of the class numbers amounts to 4 and the total of z-score amounts is 5,2 is. The joint evaluation of the fine particles content Cd, Co, Cu, Ni, Pb and Cr as a group is based on the practice employed frequently in other interlaboratory tests, where for a "successful" participation, a "correct" determination of 80 % (here 83 %) of the investigation parameters is presupposed. For the present case this means that 5 of 6 heavy metals have to be determined successfully.