Details test and examination criteria for replacement draft hoods for use on installed appliances using natural, manufactured and mixed gases, liquefied petroleum gases and LP gas-air mixtures, and for use on appliances that have been converted from other fuels to the above gases. They are suitable for use with gas appliances required to be installed with a draft hood as specified in the National Fuel Gas Code, ANSI Z223.1, in the event the appliance designs do not incorporate draft hoods.