Increasing regulatory activity requires that the coatings industry become familiar with regulatory terms from the Clean Air Act. This glossary lists common terms used in the application of air-pollution control to paints and coatings.
Absorption--The unit operation that dissolves one or more soluble components of a gas mixture in a liquid.
Add-on control device--An air pollution control device such as carbon adsorber or incinerator that reduces the pollution in an exhaust gas. The control device does not affect the process being controlled; it is "add-on" technology, as opposed to controlling pollution by altering the basic process.
Adsorption--The taking up of a material by a solid surface; concentration change at an interface. For example: carbon adsorbing VOC from an air stream.
Affected facility--Referring to a stationary source; any apparatus to which a standard is applicable.
Air-dry--A coating that dries or cures at ambient temperature.
Air-spray--Spray coating method that atomizes the coating by forcing it through a small opening at high pressure. The liquid coating is not mixed with air before exiting the nozzle.
ALAPCO--Assn. of Local Air Pollution Control Officials.
Aliphatic compounds--Organic compounds composed of open chains of carbon atoms. These include paraffins and olefins but not aromatic compounds.
Alternative method--Method of sampling and analyzing for an air pollutant that is not a reference or equivalent method but has been demonstrated to EPA's satisfaction to, in specific cases, produce results adequate for determination of compliance.
Anodic electrodeposition--The part being painted is wired to serve as the anode or electron donor. This was the first type of electrodeposition developed, but it has been largely replaced by cathodic electrodeposition, which gives better corrosion protection.
Architectural coatings--Stock type or shelf coatings formulated for service under environmental conditions and for general application on new and existing residential, commercial, institutional, and industrial structures. These are distributed through wholesale-retail channels and purchased by the general public, painters, building contractors, and others. Also referred to as trade sales paint.
Aromatic solvents--Solvents made of compounds that contain an unsaturated ring of carbon atoms, typified by benzene's structure. Xylene and toluene are aromatic solvents used in coatings.
Attainment area--An area considered to have air quality as good as or better than the national ambient air quality standards (NAAQS), as defined by Section 107 of the Clean Air Act. It may be an attainment area for one pollutant and a nonattainment area for others.
Automatic electrostatic spray application--Electrostatic spray applied by a robot or other self-acting mechanism. Automatic electrostatic spray is an efficient way to transfer coatings to the substrate, reducing pollution that otherwise results from paint overspray.
BACM--See best available control measures.
Baking temperatures--Recommended temperatures of the curing oven that ensure a coated part is baked or cured to obtain optimum properties. The amount of volatile material released from the coating is sometimes increased if baking temperature rises.
Banking--A system of recording qualified emission reductions for later use in bubble, offset, or netting transactions.
Basecoat/clearcoat--A two-step finish coat system in which a highly pigmented, often metallic, basecoat is followed by a thicker clearcoat. It results in a finish with high-gloss characteristics.
Bell--An electrostatic spray device that has a paint applicator shaped like a bell. This bell revolves rapidly so that paint, metered to the center of the bell, is thrown by centrifugal force off the edge as a fine mist. High electrostatic voltage maintained on the bell contributes to keeping the paint spray a fine mist, allowing electrostatic forces to draw the paint very efficiently with little overspray. The bell is one of the most efficient pieces of spray equipment with transfer efficiencies commonly over 90%. High-solids coatings are sprayed more easily with high-speed (over 30,000 revolutions per minute) bells than with other spray equipment.
Best available control measures (BACM)--Also known as best available control technology (BACT). An emission limitation based on the maximum degree of emission reduction that (considering energy, environmental, economic impacts, and other costs) is achievable through application of production processes and available methods, systems, and techniques. In no event does BACM permit emissions in excess of those allowed under any applicable NSPS or NESHAP. It is applicable on a case-by-case basis for each new (or modified) emission source located in areas attaining the national ambient air quality standards (NAAQS). It applies to each pollutant regulated under the Clean Air Act, and it is concerned with prevention of significant deterioration (PSD). See Sections 165(a)(4) and 169 of the CAA.
Beverage can--A can used for soft drinks or beer.
Binder--Nonvolatile, liquid portion of a coating. When the paint dries, the binder becomes part of the solid film. It binds the pigment particles together and cements the paint film to the substrate.
Blushing--A film defect appearing as a milky opalescence that sometimes appears as the film or lacquer dries. It is caused as the rapid solvent evaporation cools the surface, and moisture from the air condenses on the wet coating. This condition is commonly encountered in the wood furniture industry.
Bubble--A system whereupon existing sources propose alternative means to comply with a set of emission limitations. Under the bubble concept, sources can control more than required at one emission point where control costs are relatively low in return for a comparable relaxation of controls at a second emission point where costs are high. The bubble policy was first announced in the Federal Register, December 11, 1979 (44 FR 71779), and changes were proposed on April 7, 1982.
CAA--See Clean Air Act.
Capture--The containment or recovery of emissions from a process for direction into a duct that is exhausted through a stack or sent to a control device. The overall abatement of emissions from a process with an add-on control device is a function of the capture efficiency and the control device.
Capture device--A hood, enclosed room, floor sweep, or other means of collecting solvent or pollutants into a duct. The pollutant is then directed to a pollution control device such as an incinerator or carbon adsorber. The term is used loosely to include the control device.
Capture efficiency--The fraction of all organic vapors generated by a process directed to an abatement or recovery device.
Carbon adsorber--An add-on control device that uses activated carbon to adsorb VOCs from a gas stream. The VOCs are later recovered from the carbon, usually by steam stripping.
Cast coating--A film made by depositing a layer of plastic material in a solution, a dispersion, or a molten state onto a (usually) smooth, solid surface. The plastic is solidified and removed as a film having the same surface as the one on which it was formed.
Catalytic incinerator--A control device that oxidizes VOC by using a catalyst to promote the combustion process. The catalyst allows the combustion process to proceed at a lower temperature (usually 600 to 800 [degrees] F) than a conventional thermal incinerator would require (1100 to 1400 [degrees] F), resulting in fuel savings and lower cost incineration.
Cathodic electrodeposition--An electrodeposition paint …