Terms used in this subpart are defined in the CAA, in 40 CFR 63.2, and in this section as follows:

Add-on control means an air pollution control device, such as a thermal oxidizer or carbon adsorber, that reduces pollution in an air stream by destruction or removal before discharge to the atmosphere.

As-applied means the condition of a coating at the time of application to a substrate, including any added solvent.

As purchased means the condition of a coating, printing, slashing, dyeing, or finishing material as delivered to the affected source, before alteration.

Capture device means a hood, enclosure, room, floor sweep, or other means of containing or collecting emissions and directing those emissions into an add-on air pollution control device.

Capture efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device.

Capture system means one or more capture devices intended to collect emissions generated by a web coating/printing or dyeing/finishing operation in the use of regulated materials, both at the point of application and at subsequent points where emissions from the regulated materials occur, such as flashoff, drying, or curing. As used in this subpart, multiple capture devices that collect emissions generated by a web coating/printing or dyeing/finishing operation are considered a single capture system.

Cleaning material means a solvent used to remove contaminants and other materials, such as dirt, grease, or oil, from a textile before a web coating/printing operation (surface preparation) or from equipment associated with the web coating/ printing operation, such as tanks, rollers, rotary screens, and knife or wiper blades. Thus, it includes any cleaning material used in the web coating and printing subcategory for surface preparation of substrates or process operation equipment cleaning or both with the exception of cleaning material applied to the substrate using handheld, non-refillable aerosol containers.

Coating means the application of a semi-liquid coating material to one or both sides of a textile web substrate. Once the coating material is dried (and cured, if necessary), it bonds with the textile to form a continuous solid film for decorative, protective, or functional purposes. Coating does not include finishing where the fiber is impregnated with a chemical or resin to impart certain properties, but a solid film is not formed.

Coating material means an elastomer, polymer, or prepolymer material applied as a thin layer to a textile web. Such materials include, but are not limited to, coatings, sealants, inks, and adhesives. Decorative, protective, or functional materials that consist only of acids, bases, or any combination of these substances are not considered coating material for the purposes of this subpart. Thinning materials also are not included in this definition of coating materials, but are accounted for separately.

Coating operation means equipment used to apply cleaning materials to a web substrate to prepare it for coating material application (surface preparation), to apply coating material to a web substrate (coating application) and to dry or cure the coating material after application by exposure to heat or radiation (coating drying or curing), or to clean coating operation equipment (equipment cleaning). A single coating operation may include any combination of these types of equipment, but always includes at least the point at which a coating or cleaning material is applied and all subsequent points in the affected source where organic HAP emissions from that coating or cleaning material occur. There may be multiple coating operations in an affected source. Coating material application with handheld, non-refillable aerosol containers, touch-up markers, or marking pens is not a coating operation for the purposes of this subpart. Polyurethane foam carpet backing operations are not coating operations for the purposes of this subpart.

Container means any portable device in which a material is stored, conveyed, treated, disposed of, or otherwise handled.

Continuous parameter monitoring system means the total equipment that may be required to meet the data acquisition and availability requirements of this subpart, used to sample, condition (if applicable), analyze, and provide a record of coating or printing operation, or capture system, or add-on control device parameters.

Controlled web coating/printing or dyeing/finishing operation means a web coating/printing or dyeing/finishing operation from which some or all of the organic HAP emissions are routed through an emission capture system and add-on control device.

Deviation means:

(1) Before September 12, 2019, any instance in which an affected source subject to this subpart or an owner or operator of such a source:

(i) Fails to meet any requirement or obligation established by this subpart including but not limited to any emission limit, or operating limit, or work practice standard;

(ii) 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

(iii) Fails to meet any emission limit, or operating limit, or work practice standard in this subpart during startup, shutdown, or malfunction regardless of whether or not such failure is permitted by this subpart; and

(2) On and after September 12, 2019, any instance in which an affected source subject to this subpart or an owner or operator of such a source:

(i) Fails to meet any requirement or obligation established by this subpart including but not limited to any emission limit, or operating limit, or work practice standard; or

(ii) 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.

Dyeing means the process of applying color to the whole body of a textile substrate with either natural or synthetic dyes. Dyes are applied to yarn, fiber, cord, or fabric in aqueous solutions and dried before or after finishing, depending on the process. Continuous dyeing processes include, but are not limited to thermosol, pad/steam, pad/dry, and rope range dyeing. Batch dyeing processes include, but are not limited to, jet, beck, stock, yarn, kier, beam, pad, package and skein dyeing.

Dyeing materials means the purchased dyes and dyeing auxiliaries that are used in the dyeing process. The dyes are the substances that add color to textiles through incorporation into the fiber by chemical reaction, absorption or dispersion. Dyeing auxiliaries are various substances that can be added to the dyebath to aid dyeing. Dyeing auxiliaries may be necessary to transfer the dye from the dyebath to the fiber or they may provide improvements in the dyeing process or characteristics of the dyed fiber.

Dyeing operation means the collection of equipment used to dye a textile substrate and includes equipment used for dye application, dye fixation, and textile substrate rinsing and drying. A single dyeing operation may include any combination of these types of equipment, but always includes at least the point at which a dyeing material is applied and all subsequent points in the affected source where organic HAP emissions from that dyeing material occur. There may be multiple dyeing operations in an affected source. Dyeing material application with handheld, non-refillable aerosol containers, touch-up markers, brushes, or marking pens is not a dyeing operation for the purposes of this subpart.

Emission limitation means an emission limit, operating limit, or work practice standard.

Enclosure means a structure that surrounds a source of emissions and captures and directs the emissions to an add-on control device.

Fabric means any woven, knitted, plaited, braided, felted, or non-woven material made of filaments, fibers, or yarns including thread. This term includes material made of fiberglass, natural fibers, synthetic fibers, or composite.

Finishing means the chemical treatment of a textile (e.g., with resins, softeners, stain resist or soil release agents, water repellants, flame retardants, antistatic agents, or hand builders) that improves the appearance and/or usefulness of the textile substrate.

Finishing materials means the purchased substances (including auxiliaries added to the finish to improve the finishing process or the characteristics of the finished textile) that are applied individually or as mixtures to textile substrates to impart desired properties.

Finishing operations means the collection of equipment used to finish a textile substrate including chemical finish applicator(s), flashoff area(s) and drying or curing oven(s).

Laminated fabric means fabric composed of a high-strength reinforcing base fabric between two plies of flexible thermoplastic film. Two or more fabrics or textiles or a fabric and a paper substrate may be bonded with an adhesive to form a laminate. The bonding of a fabric substrate to paper is not subject to the requirements of this subpart.

Manufacturer's formulation data means data on a material (such as a coating, printing, slashing, dyeing and finishing) that are supplied by the material manufacturer based on knowledge of the ingredients used to manufacture that material, rather than based on testing of the material. Manufacturer's formulation data may include, but are not limited to, information on density, organic HAP content, and coating, printing, dyeing, slashing, finishing, thinning, or cleaning material content.

Mass fraction of organic HAP means the ratio of the mass of organic HAP to the mass of a material in which it is contained; kg of organic HAP per kg of material.

Month means a calendar month or a pre-specified period of 28 days to 35 days to allow for flexibility in recordkeeping when data are based on a business accounting period.

No organic HAP means no organic HAP in table 5 to this subpart is present at 0.1 percent by mass or more and no organic HAP not listed in table 5 to this subpart is present at 1.0 percent by mass or more. The organic HAP content of a regulated material is determined according to § 63.4321(e)(1).

Operating scenario means for a dyeing/finishing process operation or group of process operations, the combination of operating conditions (including but not limited to, type of substrate, type and mass fraction of organic HAP in dyeing/finishing materials applied, and the process operation temperature and pressure) affecting the fraction of organic HAP applied in dyeing and finishing operations discharged to wastewater. For example, a dyeing process operation run at atmospheric pressure would be a different operating scenario from the same dyeing process operation run under pressure.

Organic HAP content means the mass of organic HAP per mass of solids for a coating or printing material calculated using Equation 1 of § 63.4321. The organic HAP content is determined for the coating or printing material as purchased.

Organic HAP overall control efficiency means the total efficiency of a control system, determined either by:

(1) The product of the capture efficiency as determined in accordance with the requirements of § 63.4361 and the control device organic emissions destruction or removal efficiency determined in accordance with the requirements of § 63.4362; or

(2) A liquid-liquid material balance in accordance with the requirements of § 63.4341(e)(5) or (f)(5) or § 63.4351(d)(5).

Permanent total enclosure (PTE) means a permanently installed enclosure that meets the criteria of Method 204 of appendix M, 40 CFR part 51, for a PTE and that directs all the exhaust gases from the enclosure to an add-on control device.

Point of determination means each point where process wastewater exits the dyeing/finishing process unit.

Printing means the application of color and patterns to textiles, usually in the form of a paste, using a variety of techniques including, but not limited to roller, rotary screen, and ink jet printing. After application of the printing material, the textile usually is treated with steam, heat, or chemicals to fix the color.

Printing material means the purchased substances, usually including gums or thickeners, dyes and appropriate chemicals such as defoamers and resins that are mixed to produce the print pastes applied to textile substrates as patterns and colors.

Printing operation means equipment used to apply cleaning materials to a web substrate to prepare it for printing material application (surface preparation), to apply printing material to one or both sides of a web substrate (printing application) and to dry or cure the printing material after application by exposure to heat or radiation (printing material drying or curing), or to clean printing operation equipment (equipment cleaning). A single printing operation may include any combination of these types of equipment, but always includes at least the point at which a printing or cleaning material is applied and all subsequent points in the affected source where organic HAP emissions from that printing or cleaning material occur. There may be multiple printing operations in an affected source.

Publically owned treatment works or POTW means any device or system used in the treatment (including recycling and reclamation) of municipal sewage or industrial wastes of a liquid nature which is owned by a “State” or “municipality” (as defined by section 502(4) of the CWA). This definition includes sewers, pipes or other conveyances only if they convey wastewater to a POTW providing treatment.

Regulated materials means the organic-containing materials that are used in the three printing, coating, and dyeing subcategories defined in § 63.4281(a). Organic-HAP containing regulated materials are the source of the organic HAP emissions limited by the requirements of this subpart. The specific regulated materials for each subcategory are defined in § 63.4282.

Research or laboratory operation means an operation whose primary purpose is for research and development of new processes and products that is conducted under the close supervision of technically trained personnel and is not engaged in the manufacture of final or intermediate products for commercial purposes, except in a de minimis manner.

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

Slashing means the application of a chemical sizing solution to warp yarns prior to weaving to protect against snagging or abrasion that could occur during weaving.

Slashing materials, also known as sizing, means the purchased compounds that are applied to warp yarns prior to weaving. Starch, gelatin, oil, wax, and manufactured polymers such as polyvinyl alcohol, polystyrene, polyacrylic acid and polyacetates are used as sizing compounds.

Slashing operation means the equipment used to mix and prepare size for application and the slasher, which is the equipment used to apply and dry size on warp yarn.

Solids means the nonvolatile portion of the coating and printing materials that makes up the dry film on a coated substrate and the pattern or color on a printed substrate.

Startup, initial means the first time equipment is brought online in a facility.

Surface preparation means chemical treatment of part or all of a substrate to prepare it for coating or printing material application.

Temporary total enclosure means an enclosure constructed for the purpose of measuring the capture efficiency of pollutants emitted from a given source as defined in Method 204 of appendix M, 40 CFR part 51.

Textile means any one of the following:

(1) Staple fibers and filaments suitable for conversion to or use as yarns, or for the preparation of woven, knit, or nonwoven fabrics;

(2) Yarns made from natural or manufactured fibers;

(3) Fabrics and other manufactured products made from staple fibers and filaments and from yarn; and

(4) Garments and other articles fabricated from fibers, yarns, or fabrics.

Thinning material means an organic solvent that is added to a coating or printing material after the coating or printing material is received from the supplier.

Total volatile hydrocarbon (TVH) means the total amount of nonaqueous volatile organic material determined according to Methods 204A through 204C of appendix M to 40 CFR part 51 and substituting the term TVH each place in the methods where the term VOC is used. The TVH includes both VOC and non-VOC.

Uncontrolled web coating/printing or dyeing/finishing operation means acoating/printing or dyeing/finishing operation from which none of the organic HAP emissions are routed through an emission capture system and add-on control device.

Volatile organic compounds (VOC) means any compounds defined as VOC in 40 CFR 51.100(s).

Wastewater means water that is generated in a web coating, web printing, slashing, dyeing or finishing operation and is collected, stored, or treated prior to being discarded or discharged.

Web means a continuous textile substrate which is flexible enough to be wound or unwound as rolls.

[68 FR 32189, May 29, 2003, as amended at 84 FR 9630, Mar. 15, 2019; 85 FR 41150, July 8, 2020]