(1) Afterburner. A catalytic and/or thermal combustion device used to control air contaminant emissions.

(2) Coke burn-off. The coke removed from the surface of the fluid catalytic cracking unit catalyst by combustion in the catalyst regenerator.

(3) Component. Any piece of equipment which has the potential to leak volatile organic compounds when tested in the manner described in section 223.10(c) of this Part. These include, but are not limited to, pump seals, compressor seals, seal oil degassing vents, pipeline valves, flanges and other connections, pressure relief devices, process drains, and open-ended pipes. Excluded from these are valves which are not externally regulated.

(4) Fuel gas. Gas generated at a petroleum refinery or any gas generated by a refinery process unit, which is combusted separately or in any combination with any type of natural gas. Fuel gas does not include gases generated by catalytic cracking unit catalyst regenerators and fluid coking burners.

(5) Fuel gas combustion device. Any equipment, such as process heaters, boilers and flares, used to combust fuel gas, except facilities in which gases are combusted to produce sulfur or sulfuric acid.

(6) Gas service. Any equipment which processes, transfers or contains a volatile organic compound or mixture of volatile organic compounds in the gaseous phase.

(7) Hot well. The collection container for condensed volatile organic compounds.

(8) Light petroleum compound. A petroleum derivative for which the temperature at 10 percent recovery is lower than 205°C when tested in accordance with ASTM D86, Standard Method for Distillation of Petroleum Products.

(9) Liquid service. Any equipment which processes, transfers or contains a volatile organic compound or mixture of volatile organic compounds in the liquid phase.

(10) Noncondensate vapors. Gases removed from process units by a vacuum producing system. As used in this Part, the term applies to the portion of volatile organic compounds which have not become liquid in condensers.

(11) Petroleum. The oil removed from the earth and the oil derived from tar sands, shale and coal.

(12) Petroleum refinery. Any facility engaged in producing gasoline, aromatics, kerosene, distillate fuel oils, residual fuel oils, lubricants, asphalt, or other products through distillation of petroleum or through redistillation, cracking, rearrangement or reforming of unfinished petroleum derivatives.

(13) Process gas. Any gas generated by a petroleum refinery process unit, except fuel gas and process upset gas as defined in this section.

(14) Process unit turnaround. The process of shutdown, inspection, repair and start-up of reactors, fractionators, or other process units.

(15) Process upset gas. Any gas generated by a petroleum refinery process unit as a result of a start-up, shut-down, upset or malfunction.

(16) Refinery process unit. A set of components which are a part of a basic process operation, such as distillation, hydrotreating, cracking or reforming of hydrocarbons.

(17) Vacuum producing systems. Equipment used to produce and maintain a vacuum in petroleum refinery process equipment as steam ejectors which contact condensers or surface condensers and mechanical vacuum pumps.

(18) Valves not externally regulated. Valves that have no external controls, such as in-line check valves.

(19) Wastewater separators. Equipment used to separate oils and water from locations downstream of process drains.