The validation of methane detection and measurement technologies by controlled gas release

It is of increasing importance to fully validate the performance of methane detection and measurement technologies that are to be used in Leak Detection and Repair (LDAR) programs and for the traceable accounting of methane emissions. Subjecting technologies to trials involving controlled gas releases can yield key data supporting a particular methods ability to detect and quantify emissions, but only if the evaluation is carried out with an appreciation of the limits of the test method itself to replicate the real measurement scenario, and the uncertainties involved in doing so.

The UK's National Physical Laboratory performs controlled methane gas releases across a wide range of release rate magnitudes and configurations in order to test different technology types. The capabilities and performance of the facilities used in such tests will be discussed, and presented in the context of two case studies: replication of the potential emissions from an onshore shale gas site, and measurements by DIAL as a validation exercise; and the creation and emission to atmosphere of specific test gas mixtures for the testing of optical gas imaging cameras, and how this relates to their use in the real world.