Regression based on x vs. y, and lab canister difference = y - x

SlopeInterceptR2# pointsAverage difference (pptv)Stdev of difference (pptv)Lab Canister differencemax|minDC-8 vs WP-3D Ethane0.98 0.0252 140.99203523351541|416DC-8 vs BAe-146 Ethane1.29 0.08-39.2 29.40.9221603567730|266DC-8 vs WP-3D Propane FID0.93 0.0221 50.992012113712 | 55DC-8 vs WP-3D Propane MSD0.93 0.0221 40.99201253712 | 55DC-8 vs BAe-146 Propane1.1 0.10.1 2.70.881928-1298|LODDC-8 vs WP-3D n-Butane1.05 0.042 10.9820436134 | 6DC-8 vs BAe-146 n-ButaneN/AN/AN/A2N/AN/A78|LODDC-8 vs WP-3D Ethyne0.94 0.117 110.98201123485 | 46DC-8 vs BAe-146 Ethyne1.1 0.32.8 5.50.571767050|LODDC-8 vs WP-3D Benzene1.14 0.22-2 60.5719-15-18111 | 7DC-8 vs BAe-146 BenzeneN/AN/AN/A2N/AN/A-1126|LODDC-8 vs WP-3D Toluene0.91 0.103 40.891144-2780 | 8DC-8 vs BAe-146 TolueneN/AN/AN/A6N/AN/A-4210|LOD

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 + 52Apparent bias = WP-3D DC-8 = -0.02 DC-8 + 52The 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)/2Standard = -0.01 DC-8 + 26This 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 EthaneBest estimate bias = (-0.02 DC-8 + 52) (-0.01 DC-8 + 26) = -0.01 DC-8 + 26In terms of WP-3D:Recommended bias = -0.0102 WP-3D + 26.5

DC-8Recommended Bias (pptv)Ethane0.01 DC8 26Propane0.035 DC8 10.5n-Butane0.025 DC8 1Ethyne0.03 DC8 3.5Benzene-0.07 DC8 + 1Toluene0.045 DC8 1.5

WP-3DRecommended Bias (pptv)Ethane-0.0102 WP3D + 26.5Propane (FID and MSD)-0.0376 WP3D + 11.3n-Butane0.0238 WP3D + 0.95Ethyne-0.0319 WP3D + 3.7Benzene0.0614 WP3D 0.877Toluene-0.0495 WP3D + 1.65

BAe-146Recommended Bias (pptv)Ethane0.233 BAe146 56.1 Propane0.123 BAe146 10.4n-ButaneN/AEthyne0.118 BAe146 1.03BenzeneN/ATolueneN/A

DC-8 2 uncertainty: 10%WP-3D 2 uncertainty: 10%BAe-146 2 uncertainty: Reported by point* Calculated after bias correction

Comparison# of comparison points% within PI 2 uncertainties*EthaneDC-8 vs WP-3D20100%DC-8 vs BAe-1462195%PropaneDC-8 vs WP-3D FID2065%DC-8 vs WP-3D MSD2085%DC-8 vs BAe-1461995%n-ButaneDC-8 vs WP-3D2070%DC-8 vs BAe-1462100%EthyneDC-8 vs WP-3D2075%DC-8 vs BAe-14617100%BenzeneDC-8 vs WP-3D1963%DC-8 vs BAe-1462100%TolueneDC-8 vs WP-3D1136%DC-8 vs BAe-1466See residual plot

BAe-146 median reported 2 uncertaintyEthane11%Propane61%n-Butane96%Ethyne45%Benzene86%Toluene119%

Ethane

Propane

Outliers not included in average

n-Butane

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

Outlier not included in average

Ethyne

Outliers not included in average

Benzene

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

Toluene

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

Time Series Plots

Regression Plots