Method 22 is a procedure that uses the human eye to determine the total time a combustion activity causes visible emissions.
NSPS OOOO and OOOOa require affected sites to determine visible emissions from enclosed vapor combustors and flares on a monthly basis. Method 22 is the testing method authorized and required to be completed to determine if visible emissions are present from these stationary sources.
NSPS OOOO / OOOOa requires affected storage tanks to have their air emissions reduced by 95%. If an enclosed vapor combustor or flare is utilized to reduce these emissions, Method 22 testing is required to be conducted as the visible emissions test.