CSA ANSI Z21.91-2017 Ventless firebox enclosures for gas-fired unvented decorative room heaters.
Injection (Bunsen) burner — a burner employing the energy of a jet of gas to inject air for combustion into the burner and mix it with the gas.
Atmospheric injection burner — a burner in which the air at atmospheric pressure is injected into the burner by a jet of gas.
Luminous or yellow-flame burner — a burner in which secondary air only is depended on for the combustion of the gas.
Power burner — a burner in which either gas or air, or both, are supplied at pressures exceeding, for gas, the line pressure, and for air, atmospheric pressure; this added pressure being applied at the burner. A burner for which air for combustion is supplied by a fan ahead of the appliance is commonly designated as a forced-draft burner.
Premixing burner — a power burner in which all or nearly all of the air for combustion is mixed with the gas as primary air.
Pressure burner — a burner that is supplied with a gas-air mixture under pressure (usually from 0.5 to 14 Inches water column and occasionally higher).
Burner head — the portion of a burner beyond the outlet end of the mixer tube that contains the ports.
Combustible material — as pertaining to materials adjacent to or In contact with heat producing appliances, vent connectors, gas vents, chimneys, steam and hot water pipes, and warm air ducts, means materials made of or surfaced with wood, compressed paper, plant fibers, or other materials that are capable of being ignited and burned. Such materials are to be considered combustible even though flame-proofed, fire-retardant treated, or plastered.
Combustion — the rapid oxidation of fuel gases accompanied by the production of heat, or heat and light.
Combustion chamber — the portion of an appliance within which combustion occurs.
Condensate (condensation) — the liquid that separates from a gas (including flue gases) due to a reduction in temperature.
Controls — devices designed to regulate the gas, air, water, or electrical supplies to a gas appliance. These may be manual, semi-automatic, or automatic.
Cubic foot of gas — the amount of gas that would occupy 1 cubic foot when at a temperature of 60F, if saturated with water vapor and under a pressure equivalent to that of 30 inches of mercury column.
Discharge air opening — any series of openings in the same plane separated by less than 1 inch of unbroken surface between openings through which heated air is discharged. For any opening through which ambient air is drawn in and discharged at a higher temperature through the same opening, the entire opening is to be deemed the discharge air opening.ANSI Z21.91 pdf download.