Second, an independent observer from the study team noted compressor states and the time of large episodic emissions, such as blowdowns, compressor starts, etc. While episodic emissions need to be tracked and included in long-duration emissions totals, comparisons performed here exclude episodic events from OEI estimates. TD estimates made during these episodic events were eliminated from resulting comparisons. This simplication has no impact on TD-OEI comparisons; TD methods cannot reliably measure total emissions from episodic events, and the same engineering calculations would be used to estimate these emissions for both the OEI and TD estimates.