A type of flow sampler developed to monitor methane leaks from industrial sources may inadequately measure the gas, according to the New York Times. A researcher from the University of Texas made the find during a larger effort funded by the Environmental Defense Fund to characterize methane emissions across the United States. His discovery hints at the possibility that methane leaks could be exceeding estimates nationwide.
The sampler in question, the Bacharach Hi Flow Sampler, operates with two sensors: one for low methane emissions and another for higher levels. The researcher, Touche Howard, found that the sampler inadequately switches from using the low-level sensor and, if improperly calibrated, can get stuck in the low-emission measurement mode.
When the sampler malfunctions, Howard says there is no way to determine just how much measurement error is occurring. Only a few industrial methane leaks each year are responsible for most escaped methane, he notes, pointing out that poor measurements of them could skew the U.S. EPA’s methane inventory.
Howard owns a patent for a high-flow-rate sampler, the technology for which is used in the Bacharach device.