Results of Proficiency Test Gasoline (ASTM specification) March 2016

Transcription

1 Results of Proficiency Test Gasoline (ASTM specification) March 2016 Organised by: Author: Correctors: Report: Spijkenisse, the Netherlands ing. R.J. Starink dr. R.G. Visser & ing. A.S. Noordman-de Neef iis16b01astm May 2015

2 Spijkenisse, May Empty page -- page 2 of 61 Gasoline: iis16b01astm

3 Spijkenisse, May 2016 CONTENTS 1 INTRODUCTION SET UP ACCREDITATION PROTOCOL CONFIDENTIALITY STATEMENT SAMPLES STABILITY OF THE SAMPLES ANALYSES RESULTS STATISTICS GRAPHICS Z-SCORES EVALUATION EVALUATION PER TEST PERFORMANCE EVALUATION FOR THE GROUP OF LABORATORIES COMPARISON OF THE RESULTS OF MARCH 2016 WITH PREVIOUS PTS Appendices: 1. Data, statistical results and graphic results z-scores distillation ASTM D Number of participants per country Abbreviations and literature Gasoline: iis16b01astm page 3 of 61

4 Spijkenisse, May INTRODUCTION Since 1995, the (iis) organizes a proficiency scheme for Gasoline. During the annual proficiency testing program 2015/2016, it was decided to continue the round robin for the analysis of Gasoline in accordance with the most recent version of the specification ASTM D4814. In this interlaboratory study, in total, 115 laboratories in 59 different countries have registered for participation. See appendix 3 for the number of participants per country. In this report, the results of the 2016 proficiency test are presented and discussed. This report is also electronically available through the iis web site 2 SET UP The (iis) in Spijkenisse, the Netherlands, was the organizer of this proficiency test. Sample analyzes for fit-for-use and homogeneity testing were subcontracted to an accredited laboratory. In this proficiency test, the participants received, depending on their registration, 1*1 litre bottle Gasoline euro 95 (labelled #16015) and/or 1*1 litre bottle (± 75% filled) Gasoline euro 95 (labelled #16016) for DVPE only, and/or 1*1 litre bottle Gasoline euro 95 (labelled #16017) for RON/MON only. To get maximum information from this study it was decided to spike the bulk material with approx. 1.2 mg Phosphorus per liter. Participants were requested to report rounded and unrounded test results. The unrounded test results were preferably used for statistical evaluation. 2.1 ACCREDITATION The in Spijkenisse, the Netherlands, is accredited in agreement with ISO/IEC 17043:2010 (R007), since January 2000, by the Dutch Accreditation Council (Raad voor Accreditatie). This PT falls under the accredited scope. This ensures strict adherence to protocols for sample preparation and statistical evaluation and 100% confidentiality of participant s data. Feedback from the participants on the reported data is encouraged and customer s satisfaction is measured on regular basis by sending out questionnaires. 2.2 PROTOCOL The protocol followed in the organization of this proficiency test was the one as described for proficiency testing in the report iis Interlaboratory Studies: Protocol for the Organisation, Statistics and Evaluation of April 2014 (iis-protocol, version 3.3). This protocol is electronically available through the iis web site from the FAQ page. 2.3 CONFIDENTIALITY STATEMENT All data presented in this report must be regarded as confidential and for use by the participating companies only. Disclosure of the information in this report is only allowed by means of the entire report. Use of the contents of this report for third parties is only allowed by written permission of the. Disclosure of the identity of one or more of the participating companies will be done only after receipt of a written agreement of the companies involved. page 4 of 61 Gasoline: iis16b01astm

5 Spijkenisse, May SAMPLES The necessary sample material, Gasoline Euro 95 was obtained from a local petrol station in the Netherlands in September The approximately 380 litres of Gasoline was spiked with 6.07 gram Tricresylphosphate (TCP). After mixing and homogenisation in a 500 liter mixing vessel, 165 amber glass bottles of 1 litre were filled and labelled #16015 for the main round and 77 amber glass bottles of 1 litre were filled and labelled #16017 for the determination of RON/MON. The homogeneity of the subsamples #16015 and #16017 were checked by determination of Density at 15 C in accordance with ASTM D4052 on 10 stratified randomly selected samples. Density at 15 C in kg/m 3 Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Sample #16015/ Table 1: homogeneity test results of subsamples #16015 and #16017 From the remaining material, 134 bottles of 1 litre were filled with approx. 750 ml and labelled #16016 for DVPE only. The homogeneity of the subsamples #16016 was checked by determination of Dry Vapour Pressure Equivalent in accordance with ASTM D5191 on 8 stratified randomly selected samples. DVPE in psi Sample # Sample # Sample # Sample # Sample # Sample # Sample # Sample # Table 2: homogeneity test results of subsamples #16016 From the above test results (table 1 and 2), the repeatabilities were calculated and compared with 0.3 times the corresponding reproducibilities in agreement with the procedure of ISO 13528, Annex B2 in the next table: Gasoline: iis16b01astm page 5 of 61

6 Spijkenisse, May 2016 Density at 15 C in kg/m 3 DVPE in psi r (sample #16015) r (sample #16016) reference test method D4052:15 ASTM D5191: x R (ref. test method) Table 3: repeatabilities of subsamples #16015 (and #16017) and #16016 The calculated repeatabilities of the results of homogeneity tests for Density and DVPE were less than 0.3 times the reproducibilities of the reference test methods. Therefore, the homogeneities of subsamples #16015 (and #16017) and #16016 were assumed. To the participants, depending on their registration, 1*1 litre bottle of sample #16015 and/or 1*1 litre bottle (± 750 ml filled) of sample #16016 and/or 1*1 litre bottle of sample #16017 were sent on February 3, STABILITY OF THE SAMPLES The stability of Gasoline, packed in the brown glass bottles, was checked. The material was found sufficiently stable for the period of the proficiency test. 2.6 ANALYZES The participants were requested to determine API Gravity, Aromatics by FIA, Benzene, Copper Strip Corrosion, Silver corrosion, Density at 15 C, Distillation (automated or manual), Doctor Test, Existent gum (washed), Lead, Olefins by FIA, Oxidation Stability, Oxygenates (Ethanol, MTBE, Other Oxygenates, Total Oxygenates), Total Oxygen, Phosphorus, Sulphur, on sample # On sample #16016, the participants were requested to determine Total Vapour Pressure and Dry Vapour Pressure (acc. ASTM D5191 and EPA) On sample #16017, the participants were requested to determine RON and/or MON. To get comparable test results a detailed report form, on which the units were prescribed as well as the reference test methods and a letter of instructions were prepared and made available on the data entry portal A SDS and a form to confirm receipt of the samples were added to the sample package. 3 RESULTS During five weeks after sample dispatch, the test results of the individual laboratories were gathered via the data entry portal The reported test results are tabulated per determination in appendix 1 of this report. The laboratories are presented by their code numbers. Directly after the deadline, a reminder was sent to those laboratories that had not reported test results at that moment. Shortly after the deadline, the available test results were screened for suspect data. A test result was called suspect in case the Huber Elimination Rule (a robust outlier test) found it to be an outlier. The laboratories that produced these suspect data were asked to check the raw data of reported test results (no reanalyzes). page 6 of 61 Gasoline: iis16b01astm

7 Spijkenisse, May 2016 Additional or corrected test results are used for data analysis and original test results are placed under Remarks the test result tables in appendix 1. Test results that came in after the deadline were not taken into account in this screening for suspect data and thus these participants were not requested for checks. 3.1 STATISTICS Statistical calculations were performed as described in the report iis Interlaboratory Studies: Protocol for the Organisation, Statistics and Evaluation of April 2014 (iis-protocol, version 3.3). For the statistical evaluation the unrounded (when available) test results were used instead of the rounded test results. Test results reported as < or > were not used in the statistical evaluation. First, the normality of the distribution of the various data sets per determination was checked by means of the Lilliefors-test a variant of the Kolmogorov-Smirnov test and by the calculation of skewness and kurtosis. Evaluation of the three normality indicators in combination with the visual evaluation of the graphic Kernel density plot, lead to judgement of the normality being either unknown, OK, suspect or not OK. After removal of outliers, this check was repeated. Not all data sets proved to have a normal distribution, in which cases the statistical evaluation of the test results should be used with due care. In accordance with ISO 5725 the original test results per determination were submitted subsequently to Dixon s, Grubbs and/or Rosner s outlier tests. Outliers are marked by D(0.01) for the Dixon test, by G(0.01) or DG(0.01) for the Grubbs test and by R(0.01) for the Rosner s test. Stragglers are marked by D(0.05) for the Dixon test, by G(0.05) or DG(0.05) for the Grubbs test and by R(0.05) for the Rosner test. Both outliers and stragglers were not included in the calculations of averages and standard deviations. For each assigned value, the uncertainty was determined in accordance with ISO Subsequently the calculated uncertainty was evaluated against the respective requirement based on the target reproducibility in accordance with ISO When the uncertainty passed the evaluation, no remarks are made in the report. However, when the uncertainty failed the evaluation it is mentioned in the report and it will have consequences for the evaluation of the test results. Finally, the reproducibilities were calculated from the standard deviations by multiplying them with a factor of GRAPHICS In order to visualise the data against the reproducibilities from literature, Gauss plots were made, using the sorted data for one determination (see appendix 1). On the Y-axis the reported test results are plotted. The corresponding laboratory numbers are on the X-axis. The straight horizontal line presents the consensus value (a trimmed mean). The four striped lines, parallel to the consensus value line, are the +3s, +2s, -2s and -3s target reproducibility limits of the selected reference test method. Outliers and other data, which were excluded from the calculations, are represented as an x. Accepted data are represented as a triangle. Furthermore, Kernel Density Graphs were made. This is a method for producing a smooth density approximation to a set of data that avoids some problems associated with histograms. Also a normal Gauss curve was projected over the Kernel Density Graph for reference. Gasoline: iis16b01astm page 7 of 61

8 Spijkenisse, May Z-SCORES To evaluate the performance of the participating laboratories the z-scores were calculated. As it was decided to evaluate the performance of the participants in this proficiency test (PT) against the literature requirements, e.g. ASTM reproducibilities, the z-scores were calculated using a target standard deviation. This results in an evaluation independent of the variation of this interlaboratory study. The target standard deviation was calculated from the literature reproducibility by division with 2.8. In case no literature reproducibility was available, other target values were used. In some cases, a reproducibility based on former iis proficiency tests could be used. When a laboratory did use a test method with a reproducibility that is significantly different from the reproducibility of the reference test method used in this report, it is strongly advised to recalculate the z-score, while using the reproducibility of the actual test method used, this in order to evaluate whether the reported test result is fit-for-use. The z-scores were calculated in accordance with: z (target) = (test result - average of PT) / target standard deviation The z (target) scores are listed in the test result tables in appendix 1. Absolute values for z<2 are very common and absolute values for z>3 are very rare. The usual interpretation of z-scores is as follows: z < 1 good 1 < z < 2 satisfactory 2 < z < 3 questionable 3 < z unsatisfactory 4 EVALUATION In this interlaboratory study, problems were encountered with the dispatch of the samples. Participants in Afghanistan, Brazil, India, Kazakhstan, Tanzania and Turkmenistan received the samples late or not at all. For the main round (112 participants), 5 participants did not report any results and 3 participants did report the results after the deadline. For the DVPE only round (87 participants), 8 participants did not report any results and 6 participants did report the results after the deadline. For the RON/MON round (58 participants), 4 participants did not report any results and 2 participants did report the results after the deadline. Finally, 110 laboratories reported 1435 numerical test results. Observed were 25 outlying results, which is 1.7%. In proficiency studies, outlier percentages of 3% - 7.5% are quite normal. page 8 of 61 Gasoline: iis16b01astm

9 Spijkenisse, May EVALUATION PER TEST In this section, the reported test results are discussed per test. The methods, which were used by the various laboratories, are taken into account for explaining the observed differences where possible and applicable. These methods are also in the tables together with the reported test data. The abbreviations, used in these tables, are listed in appendix 4. Not all original data sets proved to have a normal Gaussian distribution. These are referred to as not OK or suspect. The statistical evaluation of these data sets should be used with due care, see also paragraph 3.1. API Gravity: This determination was not problematic. No statistical outliers were observed. The calculated reproducibility is in good agreement with the requirements of ASTM D4052:15. Aromatics by FIA: This determination was problematic. No statistical outliers were observed. However, the calculated reproducibility is not in agreement with the requirements of ASTM D1319:15. Four laboratories reported to have used a GC method. When the FIA test results (ASTM D1319 / EN15553) were evaluated separately, the average and the calculated reproducibility did not change and is again not in agreement with the requirements of ASTM D1319:15. Benzene: This determination was not problematic. Four statistical outliers were observed. However, the calculated reproducibility after rejection of the statistical outliers is in good agreement with the requirements of ASTM D3606:10. Copper strip: No problems have been observed. All participants agreed on classification 1. Silver corrosion: No problems have been observed. All participants, except one, agreed on classification 0. Density at 15 C: This determination was not problematic. Four statistical outliers were observed. However, the calculated reproducibility after rejection of the statistical outliers is in good agreement with the requirements of ASTM D4052:15. Distillation Doctor Test: The distillation was not problematic. In total only two statistical outliers were observed. All calculated reproducibilities, except for Initial Boiling Point, after rejection of the statistical outliers, are in agreement with the requirements of ASTM D86:15 for the automated and manual modes. All the laboratories agreed on the absence of Mercaptans and reported Negative. One laboratory reported sweet Gasoline: iis16b01astm page 9 of 61

10 Spijkenisse, May 2016 Existent Gum: Lead: Olefins by FIA: This determination was not problematic. Three statistical outliers were observed. However, the calculated reproducibility after rejection of the statistical outliers is in good agreement with the requirements of ASTM D381:12. The consensus value of the group was below the application range ( mg/l) of ASTM D3237:12. Therefore, no significant conclusions were drawn. This determination was problematic. No statistical outliers were observed. However, the calculated reproducibility is not in agreement with the requirements of ASTM D1319:15. Three laboratories reported to have used a GC method. When the FIA test results (ASTM D1319 / EN15553) were evaluated separately, the calculated reproducibility is somewhat larger and again not in agreement with the requirements of ASTM D1319:15. Oxidation stability: All laboratories agreed that the Oxidation Stability is >360 (or even >900) minutes. Ethanol: MTBE: This determination was problematic for a number of participants. Three statistical outliers were observed. However, the calculated reproducibility after rejection of the statistical outliers is in agreement with the requirements of ASTM D4815:15b. This determination was problematic. One statistical outlier was observed. However, the calculated reproducibility after rejection of the statistical outlier is not in agreement with the requirements of ASTM D4815:15b. The large spread may (partly) be explained by the variety of test methods used. Other Oxygenates: No other oxygenates were found positive. Therefore, no significant conclusions were drawn. Only lab 1385 reported a false positive test result for other oxygenates. Oxygen content: This determination was not problematic. Three statistical outliers were observed. However, the calculated reproducibility after rejection of the statistical outliers is in full agreement with the requirements of ASTM D4815:15b and D5599:00(2010). Phosphorus: This determination was very problematic. No statistical outliers were observed. However, the calculated reproducibility is not at all in agreement with the requirements of ASTM D3231:13. The average recovery of Phosphorus (theoretical increment of 1.21 mg Phosphorus/L) may be satisfactory, less than 81% (the actual blank of Phosphorus content is unknown). page 10 of 61 Gasoline: iis16b01astm

11 Spijkenisse, May 2016 Sulphur: TVP: DVPE: RON: MON: This determination was not problematic. One statistical outlier was observed. However, the calculated reproducibility after rejection of the statistical outlier is in full agreement with the requirements of ASTM D5453:12. This determination was not problematic. No statistical outliers were observed. The calculated reproducibility is in agreement with the requirements of ASTM D5191:15. The conversions of the measured Total Vapour Pressure to the corresponding Dry Vapour Pressure Equivalent (DVPE) as described in ASTM D5191:15 and to the U.S. EPA guidelines (40 CFR Part 80, App. E, Method 3), show in total one statistical outlier. Both calculated reproducibilities after rejection of the statistical outlier are in agreement with the respective requirements of ASTM D5191:15 and EPA guidelines. No calculations errors were found. This determination was problematic. Only one statistical outlier was observed. However, the calculated reproducibility after rejection of the statistical outlier is not in agreement with the requirements of ASTM D2699:15a. This determination was problematic. Only one statistical outlier was observed. However, the calculated reproducibility after rejection of the statistical outlier is not in agreement with the requirements of ASTM D2700:16. Gasoline: iis16b01astm page 11 of 61

12 Spijkenisse, May PERFORMANCE EVALUATION FOR THE GROUP OF LABORATORIES A comparison has been made between the reproducibility as declared by the relevant standard and the reproducibility as found for the group of participating laboratories. The average results of sample #16015, #16016 and #16017, calculated reproducibilities and reproducibilities, derived from literature standards (in casu ASTM standards) are compared in the next table. Parameter Unit n mean 2.8 * sd R (lit) API Gravity Aromatics by FIA %V/V Benzene % V/V Copper Strip 3 hrs at 50 C n.a. n.a. Silver Corrosion 3 hrs at 50 C n.a. n.a. Density at 15 o C kg/m Distillation Auto Manual - IBP ºC %-evaporated ºC %-evaporated ºC %-evaporated ºC FBP ºC Doctor Test Negative n.a. n.a. Existent gum (washed) mg/100ml Lead as Pb mg/l 43 <2.5 n.a. n.a. Olefins by FIA %V/V Oxidation Stability min. 47 >360 n.a. n.a. -Ethanol %V/V MTBE %V/V Oxygen content %M/M Phosphorus as P mg/l Sulphur mg/kg Table 4: performance evaluation sample #16015 Parameter Unit n mean 2.8 * sd R (lit) TVP psi DVPE acc. to ASTM D5191 psi DVPE acc. EPA psi Table 5: performance evaluation sample #16016 Parameter Unit n mean 2.8 * sd R (lit) RON MON Table 6: performance evaluation sample #16017 Without further statistical calculations, it can be concluded that for many tests there is a (good) compliance of the group of participants with the relevant standards. The problematic tests have been discussed in paragraph 4.1. page 12 of 61 Gasoline: iis16b01astm

13 Spijkenisse, May COMPARISON OF THE PROFICIENCY TEST OF MARCH 2016 WITH PREVIOUS PTS March 2016 February 2015 February 2014 February 2013 Number of rep. Participants Number of results reported Statistical outliers Percentage outliers 1.7% 2.4% 3.8% 3.2% Table 7: comparison with previous proficiency tests In proficiency tests, outlier percentages of 3% - 7.5% are quite normal. The performance of the determinations of the proficiency tests was compared against the requirements of the respective standards. The conclusions are given in the following table: Parameter March 2016 February 2015 February 2014 February 2013 API Gravity Aromatics by FIA Benzene Density at 15 C Distillation Automated Distillation Manual /- Existent gum (washed) Lead as Pb n.e. n.e. n.e. n.e. Olefins by FIA Ethanol + +/- + +/- MTBE Oxygen content +/- +/- + +/- Phosphorus as P n.e. n.e. Sulphur +/- +/- +/- +/- TVP DVPE /- RON - + +/- + MON - +/- +/- +/- Table 8: comparison determinations against the standard The performance of the determinations against the requirements of the respective standards is listed in the above table. ++: group performed much better than the standard + : group performed better than the standard +/-: group performance equals the standard - : group performed worse than the standard -- : group performed much worse than the standard n.e.: not evaluated Gasoline: iis16b01astm page 13 of 61

14 Spijkenisse, May 2016 APPENDIX 1 Determination of API Gravity on sample #16015; lab method value mark z(targ) lab method value mark z(targ) 52 D D D D D D D D D D D D Calculation D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D Conversion D D D D D normality OK n 62 outliers 0 mean (n) st.dev. (n) R(calc.) R(D4052:15) page 14 of 61 Gasoline: iis16b01astm

15 Spijkenisse, May Kernel Density Gasoline: iis16b01astm page 15 of 61

16 Spijkenisse, May 2016 Determination of Aromatics by FIA on sample #16015; results in %V/V lab method value mark z(targ) lab method value mark z(targ) D D D C D D D D D D D D D D D ISO D D D D D D D D D D D D D D C D D EN D D D D ISO D EN D D D D D D D D Only D1319/EN15553 data normality OK OK n outliers 0 0 mean (n) st.dev. (n) R(calc.) R(D1319:15) Lab 323 : first reported 35.5 Lab 922: first reported 35.6 page 16 of 61 Gasoline: iis16b01astm

17 Spijkenisse, May Kernel Density Gasoline: iis16b01astm page 17 of 61

18 Spijkenisse, May 2016 Determination of Benzene on sample #16015; results in %V/V lab method value mark z(targ) lab method value mark z(targ) D D D D D D D D D D R(0.01) D D D D ISO EN EN ISO EN INH-M D D D D ISO D EN D D D EN D D D D R(0.01) EN D EN R(0.01) EN EN R(0.01) ISO EN EN EN EN D D EN D D EN D D D D D normality not OK n 52 outliers 4 mean (n) st.dev. (n) R(calc.) R(D3606:10) Compare R(D5580) = page 18 of 61 Gasoline: iis16b01astm

19 Spijkenisse, May Kernel Density Gasoline: iis16b01astm page 19 of 61

20 Spijkenisse, May 2016 Determination of Copper corrosion 3hrs at 50 C on sample #16015; lab method value mark z(targ) lab method value mark z(targ) 52 D130 1a D130 1a D130 1a D130 1A D130 1A D130 1a D130 1A D130 1a D130 1a D130 1A D130 1a D130 1a D130 1a D130 1A D130 1A D130 1A D130 1a D130 1a D130 1A D130 1a D130 1A D130 1A D130 1a D130 1a ISO2160 1A D130 1a D130 1a D130 1a D130 1A D130 1A D130 1A D130 1a D130 1A D130 1a D130 1A D130 1a D130 1b D130 1a ISO2160 1A D130 1a D130 1A D130 1a D130 1a D130 1a D130 1A D130 1a D130 1A D130 1a D130 1A D130 1a D130 1a D130 1a D130 1A D130 1a D D D130 1a D130 1a D130 1a ISO IP154 1a D130 1a ISO D130 1A D130 1A D130 1a D130 1A D130 1a ISO2160 1a D130 1A D130 1A D130 1a D130 1a ISO D130 1a D ISO2160 1A D130 1b D130 1A D130 1a D130 1a D130 1a D130 1a D130 1a D130 1a ISO2160 1a D130 1a D130 1a normality n.a. n 88 outliers n.a. mean (n) 1 st.dev. (n) n.a. R(calc.) n.a. R(D130:12) n.a. page 20 of 61 Gasoline: iis16b01astm

21 Spijkenisse, May 2016 Determination of Silver corrosion 3hrs at 50 C on sample #16015; lab method value mark z(targ) lab method value mark z(targ) 52 D7667-A D7671-A D7671-A D7671-A D7671-A D7671-A D7671-A D7671-A D7671-A D7667-A D7671-A D7671-A D7671-A D7671-A D7667-A D7671-A D7671-A D7671-A D7671-A D7671-A Zero D7671-A D7667-A D normality n.a. n 23 outliers n.a. mean (n) 0 st.dev. (n) n.a. R(calc.) n.a. R(D7671:10(2015)) n.a. Gasoline: iis16b01astm page 21 of 61

22 Spijkenisse, May 2016 Determination of Density at 15 C on sample #16015; results in kg/m 3 lab method value mark z(targ) lab method value mark z(targ) 52 D D D D D D D R(0.05) D D D D D D D C D D D D D D D ISO D D D D D D D D D D D D D IP D ISO D D D D D D D D D D D D D D D D R(0.05) D D D D D D R(0.01) D D ISO IP D D C D D D D D ISO D D D ISO D D D D D ISO C D D D D D D D ISO D ISO D ISO D D D D D ISO D R(0.01) D D normality OK n 100 outliers 4 mean (n) st.dev. (n) R(calc.) 0.66 R(D4052:15) 2.17 Lab 158: reported kg/m 3 Lab 355: first reported Lab 1810: first reported page 22 of 61 Gasoline: iis16b01astm

23 Spijkenisse, May Kernel Density Gasoline: iis16b01astm page 23 of 61

24 Spijkenisse, May 2016 Determination of Distillation at 760 mm Hg ASTM D86 on sample #16015; results in C lab method mode IBP mark 10% eva mark 50% eva mark 90% eva mark FBP mark 52 D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Manual R(5) D86 Manual D86 Manual D86 Manual D86 Manual D86 Manual D86 Manual D86 Manual D86 Manual D86 Manual D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated 37.1 C D86 Automated D86 Manual D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D D86 Automated D86 Automated D86 Automated D86 Automated D86 Manual D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Manual D86 Automated R(1) ISO3405 Automated IP123 Automated D86 Automated D86 Automated C D86 Automated D86 Automated page 24 of 61 Gasoline: iis16b01astm

25 Spijkenisse, May IP123 Automated D86 Automated D86 Manual D86 Automated D86 Automated D86 Manual D86 Automated D INH-2177 Manual D86 Manual D86 Automated D86 Automated D86 Automated D86 Automated Automated D86 Automated D86 Automated D86 Automated D86 Manual ISO3405 Automated D86 Automated D86 Automated D86 Automated D86 Automated D86 Automated Automated ISO ISO ISO3405 Automated D86 Automated D86 Automated ISO3405 Automated D normality OK suspect suspect not OK OK n outliers mean (n) st.dev. (n) R(calc.) R(D86:15) Automated Compare R(D86:15) Manual Lab 340:; first reported 31.1 Lab 1066: first reported 57.6 Gasoline: iis16b01astm page 25 of 61

26 Spijkenisse, May 2016 page 26 of 61 Gasoline: iis16b01astm Kernel Density Initial Boiling Point Kernel Density 10% evaporated Kernel Density 50% evaporated Kernel Density 90% evaporated Kernel Density Final Boiling Point

27 Spijkenisse, May 2016 Determination of Doctor Test on sample #16015; lab method value mark z(targ) lab method value mark z(targ) 52 D4952 Neg D4952 negative D4952 Negative D4952 Negative IP30 Negative D4952 Negative D4952 Negative D4952 NEG IP30 Negative D4952 Sweet IP30 Negative D4952 neg D4952 Negative D4952 Negative D4952 neg D4952 Negative D4952 Negative D4952 Negative D4952 Negative D4952 negative D4952 negative D4952 Negative D4952 Negative IP30 Negative D4952 Negative D4952 Negative IP30 Negative IP30 Negative D4952 Negative D4952 negative D4952 Negative D4952 Negative D4952 Negative D4952 Negative IP30 negative D4952 Negative D4952 neg D4952 negative D4952 Negative IP30 neg D4952 Negative D4952 NEG IP30 Negative D4952 Negative IP30 Negative D4952 Negative IP30 negative IP30 negative D4952 negative IP30 Negative D4952 Negative IP30 Negative D4952 Negative D4952 Negative D4952 negative normality n.a. n 54 outliers n.a. mean (n) Negative st.dev. (n) n.a. R(calc.) n.a. R(D4952:12) n.a. Gasoline: iis16b01astm page 27 of 61