Assessing the Performance of Emerging and Existing Continuous Monitoring Solutions under a Single-blind Controlled Testing Protocol

Continuous Monitoring (CM) solutions have been identified as a method to address methane emissions at oil and gas (O&G) facilities, as these solutions can facilitate faster emission detection and repair compared to traditional survey methods. This study tested 13 CM solutions over 12 weeks using single-blind controlled testing. Controlled release rates ranged from 0.08 to 6.75 kg CH4/hr and lasted 18 minutes to 8 hours. Six solutions demonstrated 90 % method detection limits (DL90s) within the range of controlled releases, from 0.5 [0.3, 0.6] kg CH4/hr to 6.7 [5.9, 8.0] kg CH4/hr. Of the six solutions, four had False Positive (FP) rates between 7.8% and 14.0% (less than 15%), and four had False Negative rates (FN) of 8.0% to 34.1% (less than 50%). Compared with Ilonze et al., these results show retested solutions balancing method sensitivity with FP and FN rates. All scanning/imaging solutions had high localization (≥ 40%) precision and accuracy to the equipment unit. Eleven of the 13 solutions were tested for quantification. Single quantification estimates exhibited high relative quantification errors, outside the -90 % to 1000% range. The mean quantification error ranged from 33 [0.9, 66] %, 95% CI to 1326 [1003, 1648] %, 95 % CI for small emissions, between 0.1 and 1 kg CH4/hr, and from 3 [-20, 26] %, 95% CI to 3578 [-2832, 9988] %, 95% CI for larger emissions, greater than 1 kg CH4/hr. There were 3 and 9 solutions in the small and large emissions categories, respectively, that had less than 100% relative quantification error. Relative to previous studies, errors in quantification estimates decreased, as did FN and FP rates, with improved DL90s for two of the four retested solutions. These findings highlight that continuous, rigorous testing enhances solution performance, with notable improvements observed across multiple testing programs using the same test protocol.