Partners provided maintenance event data for two periods, July 1 through July 31, 2021 and September 19 through October 1, 2021. Except for three long-duration pipeline leaks, the 5031 reported maintenance events represent episodic venting i.e. short-duration, vented, emissions. Events provided to the study team were later aggregated by the operators and included in regulatory reporting. Partners reported events from their internal tracking systems, which varied between partners in both classication of events and which events were recorded. To provide consistent treatment, the study team worked with the partners to classify events into 10 categories, some with sub-categories: Blowdown, Bradenhead, Compression, Hot Oiling Flowline, Pigging, Pipeline Leak, Swab, Tank, Unloading and Well.