Terms used in this subpart are defined in the CAA; 40 CFR 60.2; 60.171; 61.02; 61.31; 61.61; 63.2; and in this section as follows:

Alloy furnace means any furnace used to melt alloys or to produce zinc that contains alloys.

Anode casting furnace means any furnace that melts materials to produce the anodes used in the electrolytic process for the production of zinc.

Bag leak detection system means a system that is capable of continuously monitoring the relative particulate matter (dust) loadings in the exhaust of a baghouse to detect bag leaks and other conditions that result in increases in particulate loadings. A bag leak detection system includes, but is not limited to, an instrument that operates on triboelectric, electrodynamic, light scattering, light transmittance, or other effect to continuously monitor relative particulate matter loadings.

Cadmium melting furnace means any furnace used to melt cadmium or produce cadmium oxide from the cadmium recovered in the zinc production process.

Capture system means the collection of equipment used to capture gases and fumes released from one or more emissions points and then convey the captured gas stream to a control device. A capture system may include, but is not limited to, the following components as applicable to a given capture system design: duct intake devices, hoods, enclosures, ductwork, dampers, manifolds, plenums, and fans.

Deviation means any instance in which an affected source subject to this subpart, or an owner or operator of such a source:

(1) Fails to meet any requirement or obligation established by this subpart, including but not limited to any emissions limitation or work practice standard;

(2) Fails to meet any term or condition that is adopted to implement an applicable requirement in this subpart and that is included in the operating permit for any affected source required to obtain such a permit; or

(3) Fails to meet any emissions limitation or work practice standard in this subpart during startup, shutdown, or malfunction, regardless of whether or not such failure is permitted by this subpart.

Primary beryllium production facility means any establishment engaged in the chemical processing of beryllium ore to produce beryllium metal, alloy, or oxide, or performing any of the intermediate steps in these processes. A primary beryllium production facility may also be known as an extraction plant.

Primary zinc production facility means an installation engaged in the production, or any intermediate process in the production, of zinc or zinc oxide from zinc sulfide ore concentrates through the use of pyrometallurgical techniques.

Responsible official means responsible official as defined in 40 CFR 70.2.

Roaster means any facility in which a zinc sulfide ore concentrate charge is heated in the presence of air to eliminate a significant portion (more than 10 percent) of the sulfur contained in the charge.

Sintering machine means any furnace in which calcines are heated in the presence of air to agglomerate the calcines into a hard porous mass called sinter.

Sulfuric acid plant means any facility producing sulfuric acid from the sulfur dioxide (SO2) in the gases from the roaster.

Work practice standard means any design, equipment, work practice, or operational standard, or combination thereof.

Zinc cathode melting furnace means any furnace used to melt the pure zinc from the electrolytic process.