Terms used in this subpart are defined in the Clean Air Act, in §63.2, or in this section as follows:

Aerospace and air filtration products means bonded wool fiberglass insulation manufactured for the thermal and acoustical insulation of aircraft and/or the air filtration markets. For the purposes of this subpart, a production line that manufactures these types of products for 75 percent or more of the line's annual operating hours is considered to be an aerospace and air filtration products line.

Bag leak detection system means systems that include, but are not limited to, devices using triboelectric, light scattering, and other effects to monitor relative or absolute particulate matter (PM) emissions.

Bonded means wool fiberglass to which a phenol-formaldehyde binder has been applied.

Building insulation means bonded wool fiberglass insulation, having a loss on ignition of less than 8 percent and a density of less than 32 kilograms per cubic meter (kg/m3) (2 pounds per cubic foot [lb/ft3]).

Cold top electric furnace means an all-electric glass-melting furnace that operates with a temperature of 120 °C (250 °F) or less as measured at a location 46 to 61 centimeters (18 to 24 inches) above the molten glass surface.

Flame attenuation means a process used to produce wool fiberglass where molten glass flows by gravity from melting furnaces, or pots, to form filaments that are drawn down and attenuated by passing in front of a high-velocity gas burner flame.

Gas-fired glass-melting furnace means a unit comprising a refractory vessel in which raw materials are charged, melted at high temperature using natural gas and other fuels, refined, and conditioned to produce molten glass. The unit includes foundations, superstructure and retaining walls, raw material charger systems, heat exchangers, exhaust system, refractory brick work, fuel supply and electrical boosting equipment, integral control systems and instrumentation, and appendages for conditioning and distributing molten glass to forming processes. The forming apparatus, including flow channels, is not considered part of the gas-fired glass-melting furnace. Cold-top electric furnaces as defined in this subpart are not gas-fired glass-melting furnaces.

Glass-melting furnace means a unit comprising a refractory vessel in which raw materials are charged, melted at high temperature, refined, and conditioned to produce molten glass. The unit includes foundations, superstructure and retaining walls, raw material charger systems, heat exchangers, melter cooling system, exhaust system, refractory brick work, fuel supply and electrical boosting equipment, integral control systems and instrumentation, and appendages for conditioning and distributing molten glass to forming processes. The forming apparatus, including flow channels, is not considered part of the glass-melting furnace.

Glass pull rate means the mass of molten glass that is produced by a single glass-melting furnace or that is used in the manufacture of wool fiberglass at a single manufacturing line in a specified time period.

Hazardous Air Pollutant (HAP) means any air pollutant listed in or pursuant to section 112(b) of the Clean Air Act.

Heating, ventilation, and air conditioning (HVAC) products means bonded wool fiberglass insulation manufactured for use in HVAC systems for the distribution of air or for thermal and acoustical insulation of HVAC distribution lines. For the purposes of this subpart, a production line that manufactures these types of products for 75 percent or more of the line's annual operating hours is considered to be an HVAC products line.

Heavy-density product means bonded wool fiberglass insulation manufactured on a flame attenuation manufacturing line and having a loss on ignition of 11 to 25 percent and a density of 8 to 48 kg/m3 (0.5 to 3 lb/ft3).

Incinerator means an enclosed air pollution control device that uses controlled flame combustion to convert combustible materials to noncombustible gases. For the purposes of this subpart, the term “incinerator” means “regenerative thermal oxidizer”.

Loss on ignition (LOI) means the percent decrease in weight of wool fiberglass after it has been ignited. The LOI is used to monitor the weight percent of binder in wool fiberglass.

Manufacturing line means the manufacturing equipment for the production of wool fiberglass that consists of a forming section where molten glass is fiberized and a fiberglass mat is formed and which may include a curing section where binder resin in the mat is thermally set and a cooling section where the mat is cooled.

New source means any affected source that commences construction or reconstruction after March 31, 1997 for purposes of determining the applicability of the emission limits in rows 1, 2 and 7 through 11 in Table 2. New source means any affected source that commences construction or reconstruction after November 25, 2011 for purposes of determining the applicability of all other emissions limits.

Original equipment manufacturer (OEM) products means bonded wool fiberglass insulation manufactured for OEM entities that fabricate the insulation into parts used as thermal or acoustical insulation in products including, but not limited to, appliances, refrigeration units, and office interior equipment. For the purposes of this subpart, a production line that manufactures these types of products for 75 percent or more of the line's annual operating hours is considered to be an OEM products line.

Pipe product means bonded wool fiberglass insulation manufactured on a flame attenuation manufacturing line and having a loss on ignition of 8 to 14 percent and a density of 48 to 96 kg/m3 (3 to 6 lb/ft3). For the purposes of this subpart, a production line that manufactures these types of products for 75 percent or more of the line's annual operating hours is considered to be a pipe product line.

Rotary spin means a process used to produce wool fiberglass building insulation by forcing molten glass through numerous small orifices in the side wall of a spinner to form continuous glass fibers that are then broken into discrete lengths by high-velocity air flow. Any process used to produce bonded wool fiberglass building insulation by a process other than flame attenuation is considered rotary spin.

Wool fiberglass means insulation materials composed of glass fibers made from glass produced or melted at the same facility where the manufacturing line is located.

Wool fiberglass manufacturing facility means any facility manufacturing wool fiberglass on a rotary spin manufacturing line or on a flame attenuation manufacturing line.

[64 FR 31709, June 14, 1999, as amended at 80 FR 45334, July 29, 2015; 82 FR 60883, Dec. 26, 2017]