FAQ > Rule Subparts > Subpart Y. Petroleum Refineries > Q702. For a startup, shutdown, or malfunction (SSM) event lasting several days, should the flare flow term in Equation Y-3 include the cumulative flow for the entire event or only for the day(s) during which the 500,000 scf per day threshold was exceeded?
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Q702. For a startup, shutdown, or malfunction (SSM) event lasting several days, should the flare flow term in Equation Y-3 include the cumulative flow for the entire event or only for the day(s) during which the 500,000 scf per day threshold was exceeded?


A702.While the threshold is assessed on a per day basis, the flare flow term, (FlareSSM)p, in Equation Y-­3 is defined on a per “event” basis.  If a SSM flaring event exceeds 500,000 scf in any “day” then the cumulative flare gas flow due to the entire SSM event should be included in the flare flow term, (FlareSSM)p.  For example, if a SSM event spanned two separate days and the flow due to the event was 1,000,000 scf on Day 1 and 400,000 scf on Day 2, this event would exceed the reporting threshold because it had at least one consistently designated 24-hour period (“day”) in which the cumulative flow exceeded 500,000 scf.  This would be reported as one event in Equation Y-3 and the entire 1,400,000 scf flow for the event would be used for the (FlareSSM)p term for this event. See the table below for some additional examples.


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