Q767. What are the requirements for determining the volume of gas sent to a flare?

A767. The requirements are set forth at 40 CFR 98.233(n)(1).  If you have a continuous flow measurement device on the flare, you must use the measured flow volumes to calculate the flare gas emissions.  If all of the flare gas is not measured by the existing flow measurement device, then the flow not measured can be estimated using engineering calculations based on best available data or company records.  If you do not have a continuous flow measurement device on the flare, you can install a flow measuring device on the flare or use engineering calculations based on process knowledge, company records, and best available data.