Primary findings and comparison to literature. This study has revealed a number of important considerations for deploying CMS in practice on oil and gas sites. First, care should be taken when interpreting raw CMS concentration data, as these data have different characteristics depending on the sensor type and CMS solution. We find that concentration data from metal oxide sensors have higher variability than data from laser-based sensors and can have large positive bias compared to the expected methane background of 1.9 to 2.1 ppm for the study region. Different background offsets in concentration data between CMS sensors was also found in Yang and Ravikumar and Day et al. , with Yang and Ravikumar noting that the correlation between concentration data from co-located CMS sensors was slightly higher when they were background-corrected.