1.1 These requirements cover air-heating appliances of the central furnace and unit heater types and boiler assemblies intended for burning waste oil fuels and having fuel inputs rated no more than 20 gallons/hour (75.7 liters/hour) or approximately 3,000,000 Btu/hour (3,160,000 kj/hour).

1.2 These requirements cover automatically-lighted, mechanical-atomizing type burners that typically are used with these appliances. The burner is to be factory-installed on or provided with each appliance.

1.3 The burners covered by these requirements are equipped with an automatic primary safety control to prevent the abnormal discharge of oil at the burner in the event of ignition failure or flame failure.

1.4 Requirements for the installation and use of waste oil-burning appliances are included in the Installation of Oil Burning Equipment, ANSI/NFPA 31. Waste oil-burning appliances are for use only in commercial and industrial applications.

1.5 In addition to being investigated for use with waste oils, the heating appliances covered by these requirements are investigated for use with a numerical grade of fuel oil, graded according to the Specification for Fuel Oils, ANSI/ASTM D396.

1.6 The terms "combustible" and "noncombustible", as used in these requirements, are defined in the Glossary of Terms Relating to Chimneys, Vents, and Heat-Producing Appliances, ANSI/NFPA 97M.