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

Batch ID means a unique identifier used to differentiate each individual mix batch.

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 emission limitation (including any operating limit);

(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 emission limitation (including any operating limit) in this subpart during startup, shutdown, or malfunction, regardless of whether or not such failure is permitted by this subpart.

Friction ingredients means any of the components used in the manufacture of friction materials, excluding the HAP solvent. Friction ingredients include, but are not limited to, reinforcement materials, property modifiers, resins, and other additives.

Friction materials manufacturing facility means a facility that manufactures friction materials using a solvent-based process. Friction materials are used in the manufacture of products used to accelerate or decelerate objects. Products that use friction materials include, but are not limited to, disc brake pucks, disc brake pads, brake linings, brake shoes, brake segments, brake blocks, brake discs, clutch facings, and clutches.

HAP solvent means a solvent that contains 10 percent or more of any one HAP, as listed in section 112(b) of the Clean Air Act, or any combination of HAP that is added to a solvent mixer. Examples include hexane, toluene, and trichloroethylene.

Initial startup means the first time that equipment is put into operation. Initial startup does not include operation solely for testing equipment. Initial startup does not include subsequent startups (as defined in this section) following malfunction or shutdowns or following changes in product or between batch operations.

Large solvent mixer means a solvent mixer with a design capacity greater than or equal to 2,000 pounds, including friction ingredients and HAP solvent.

Mix batch means each batch of friction materials manufactured in a solvent mixer.

Responsible official means responsible official as defined in §63.2.

7-day block average means an averaging technique for a weekly compliance determination where the calculated values for percent HAP solvent discharged to the atmosphere are averaged together for all mix batches (for which there are valid data) in a 7-day block period according to the equation provided in §63.9520(a)(6).

Small solvent mixer means a solvent mixer with a design capacity less than 2,000 pounds, including friction ingredients and HAP solvent.

Solvent mixer means a mixer used in the friction materials manufacturing process in which HAP solvent is used as one of the ingredients in at least one batch during a semiannual reporting period. Trace amounts of HAP solvents in resins or other friction ingredients do not qualify mixers as solvent mixers.

Solvent recovery system means equipment used for the purpose of recovering the HAP solvent from the exhaust stream. An example of a solvent recovery system is a condenser.

Solvent substitution means substitution of a non-HAP material for a HAP solvent.

Startup means bringing equipment online and starting the production process.

Startup, shutdown, and malfunction plan means a plan developed according to the provisions of §63.6(e)(3).