(a) All terms used in this subpart not defined below are given the meaning in the Act and in subpart A of this part.

Bake oven means a device which uses heat to dry or cure coatings.

Dip coating means a method of applying coatings in which the part is submerged in a tank filled with the coatings.

Electrodeposition (EDP) means a method of applying coatings in which the part is submerged in a tank filled with the coatings and in which an electrical potential is used to enhance deposition of the coatings on the part.

Electrostatic spray application means a spray application method that uses an electrical potential to increase the transfer efficiency of the coatings.

Flash-off area means the portion of a surface coating operation between the coating application area and bake oven.

Flow coating means a method of applying coatings in which the part is carried through a chamber containing numerous nozzles which direct unatomized streams of coatings from many different angles onto the surface of the part.

Organic coating means any coating used in a surface coating operation, including dilution solvents, from which volatile organic compound emissions occur during the application or the curing process. For the purpose of this regulation, powder coatings are not included in this definition.

Powder coating means any surface coating which is applied as a dry powder and is fused into a continuous coating film through the use of heat.

Spray application means a method of applying coatings by atomizing and directing the atomized spray toward the part to be coated.

Surface coating operation means the system on a metal furniture surface coating line used to apply and dry or cure an organic coating on the surface of the metal furniture part or product. The surface coating operation may be a prime coat or a top coat operation and includes the coating application station(s), flash-off area, and curing oven.

Transfer efficiency means the ratio of the amount of coating solids deposited onto the surface of a part or product to the total amount of coating solids used.

VOC content means the proportion of a coating that is volatile organic compounds (VOC's), expressed as kilograms of VOC's per liter of coating solids.

VOC emissions means the mass of volatile organic compounds (VOC's), expressed as kilograms of VOC's per liter of applied coating solids, emitted from a metal furniture surface coating operation.

(b) All symbols used in this subpart not defined below are given the meaning in the Act and in subpart A of this part.

Ca = the VOC concentration in each gas stream leaving the control device and entering the atmosphere (parts per million by volume, as carbon) Cb = the VOC concentration in each gas stream entering the control device (parts per million by volume, as carbon) Cf = the VOC concentration in each gas stream emitted directly to the atmosphere (parts per million by volume, as carbon) Dc = density of each coating, as received (kilograms per liter) Dd = density of each diluent VOC-solvent (kilograms per liter) Dr = density of VOC-solvent recovered by an emission control device (kilograms per liter) E = VOC destruction efficiency of the control device (fraction) F = the proportion of total VOC's emitted by an affected facility that enters the control device (fraction) G = the volume-weighted average mass of VOC's in coatings consumed in a calendar month per unit volume of coating solids applied (kilograms per liter) Lc = the volume of each coating consumed, as received (liters) Ld = the volume of each diluent VOC-solvent added to coatings (liters) Lr = the volume of VOC-solvent recovered by an emission control device (liters) Ls = the volume of coating solids consumed (liters) Md = the mass of diluent VOC-solvent consumed (kilograms) Mo = the mass of VOC's in coatings consumed, as received (kilograms) Mr = the mass of VOC's recovered by an emission control device (kilograms) N = the volume weighted average mass of VOC emissions to the atmosphere per unit volume of coating solids applied (kilograms per liter) Qa = the volumetric flow rate of each gas stream leaving the control device and entering the atmosphere (dry standard cubic meters per hour) Qb = the volumetric flow rate of each gas stream entering the control device (dry standard cubic meters per hour) Qf = the volumetric flow rate of each gas stream emitted directly to the atmosphere (dry standard cubic meters per hour) R = the overall VOC emission reduction achieved for an affected facility (fraction) T = the transfer efficiency (fraction) Vs = the proportion of solids in each coating (or input stream), as received (fraction by volume) Wo = the proportion of VOC's in each coating (or input stream), as received (fraction by weight)