1. SlopeInterceptR2R2 # points Average difference (pptv) Stdev of difference (pptv) Lab Canister difference max|min DC-8 vs WP-3D Ethane 0.98 ± 0.0252 ± 140.9920352335 1541|416 DC-8 vs BAe-146 Ethane 1.29 ± 0.08-39.2 ± 29.40.9221603567730|266 DC-8 vs WP-3D Propane FID 0.93 ± 0.0221 ± 50.992012113 712 | 55 DC-8 vs WP-3D Propane MSD 0.93 ± 0.0221 ± 40.99201253712 | 55 DC-8 vs BAe-146 Propane 1.1 ± 0.10.1 ± 2.70.881928-1298|LOD DC-8 vs WP-3D n- Butane 1.05 ± 0.042 ± 10.9820436134 | 6 DC-8 vs BAe-146 n- Butane N/A 2 78|LOD DC-8 vs WP-3D Ethyne 0.94 ± 0.117 ± 110.98201123485 | 46 DC-8 vs BAe-146 Ethyne 1.1 ± 0.32.8 ± 5.50.571767050|LOD DC-8 vs WP-3D Benzene 1.14 ± 0.22-2 ± 60.57195-18111 | 7 DC-8 vs BAe-146 Benzene N/A 2 -1126|LOD DC-8 vs WP-3D Toluene 0.91 ± 0.103 ± 40.891144-2780 | 8 DC-8 vs BAe-146 Toluene N/A 6 -4210|LOD Regression based on x vs. y, and lab canister difference = y - x

2. Bias Calculations All measurements were compared to DC-8. Therefore, DC-8 is chosen as a reference measurement and the regression of each instrument versus DC-8, minus DC-8 is the apparent bias. Ex. From DC-8 vs WP-3D Ethane regression: WP-3D = 0.98 DC-8 + 52 Apparent bias = WP-3D – DC-8 = -0.02 DC-8 + 52 The “reference standard” is an average of the DC-8 vs DC-8 and DC-8 vs WP- 3D apparent bias. Ex. DC-8 vs WP-3D Ethane: Standard = (-0.02 + 0)/2 DC-8 + (52 + 0)/2 Standard = -0.01 DC-8 + 26 This standard is then subtracted from each apparent bias to get the best estimate bias. After putting the best estimate bias in terms of the instrument being evaluated it is termed “recommended bias,” which is what is reported in the following slide. Ex. Best estimate bias for WP-3D Ethane Best estimate bias = (-0.02 DC-8 + 52) – (-0.01 DC-8 + 26) = -0.01 DC-8 + 26 In terms of WP-3D: Recommended bias = -0.0102 WP-3D + 26.5

3. DC-8Recommended Bias (pptv) Ethane0.01 DC8 – 26 Propane0.035 DC8 – 10.5 n-Butane0.025 DC8 – 1 Ethyne0.03 DC8 – 3.5 Benzene-0.07 DC8 + 1 Toluene0.045 DC8 – 1.5 WP-3DRecommended Bias (pptv) Ethane-0.0102 WP3D + 26.5 Propane (FID and MSD) -0.0376 WP3D + 11.3 n-Butane0.0238 WP3D + 0.95 Ethyne-0.0319 WP3D + 3.7 Benzene0.0614 WP3D – 0.877 Toluene-0.0495 WP3D + 1.65 BAe-146Recommended Bias (pptv) Ethane0.233 BAe146 – 56.1 Propane0.123 BAe146 – 10.4 n-ButaneN/A Ethyne0.118 BAe146 – 1.03 BenzeneN/A TolueneN/A

4. Comparison # of comparison points % within PI 2σ uncertainties* Ethane DC-8 vs WP-3D 20 100% DC-8 vs BAe-1462195% Propane DC-8 vs WP-3D FID 20 65% DC-8 vs WP-3D MSD 20 85% DC-8 vs BAe-1461995% n-Butane DC-8 vs WP-3D 20 70% DC-8 vs BAe-1462100% Ethyne DC-8 vs WP-3D 20 75% DC-8 vs BAe-14617100% Benzene DC-8 vs WP-3D 19 63% DC-8 vs BAe-1462100% Toluene DC-8 vs WP-3D 11 36% DC-8 vs BAe-1466See residual plot DC-8 2σ uncertainty: 10% WP-3D 2σ uncertainty: 10% BAe-146 2σ uncertainty: Reported by point * Calculated after bias correction BAe-146 median reported 2σ uncertainty Ethane11% Propane61% n-Butane96% Ethyne45% Benzene86% Toluene119%

5. Ethane

8. Propane

11. Outliers not included in average

12. n-Butane

13. Not enough BAe-146 vs DC-8 comparison points to graph.

14. Outlier not included in average

15. Ethyne

17. Outliers not included in average

18. Benzene

19. Not enough BAe-146 vs DC-8 comparison points to graph.

21. Toluene

22. Not enough BAe-146 vs DC-8 comparison points to graph.

24. Time Series Plots

37. Regression Plots