1.1 a. This Rregulation No. 24, "Control of Volatile Organic Compound Emissions", replaces and supersedes Regulation No. 24, "Control of Volatile Organic Compound Emissions" dated July 3, 1990.

1.2 b. This regulation is applicable to the sources of Volatile Organic Compounds (VOCs) as set-forth herein, except:

1.2.1 1. Sources, other than solvent metal-cleaning sources, whose emissions of Volatile Organic Compounds (VOCs) are not more than fifteen (15) pounds per day, unless other limits are specified herein, provided the emission rates are determined and certified in a manner acceptable to the Department.

1.2.2 2. Sanitary landfills conforming to the State of Delaware Statewide Solid Waste Management Plan.

1.3 c. No owner or operator shall substitute either methyl chloroform or methylene chloride for any other Volatile Organic Compound (VOC) for any solvent metal cleaning purpose on or after the effective date of this regulation.

1.4 d. The provisions of this regulation shall not apply to the startup and shutdown of equipment which operates continuously or in an extended steady-state when emissions from such equipment during startup and shutdown are governed by an Operating Permit issued pursuant to the provisions of Section 2, Regulation No. 2 2.0 of 7 DE Admin. Code 1102.

1.5 e. Any owner or operator currently permitted to operate a VOC emission source under Regulation No. 2 7 DE Admin. Code 1102 or the previous Regulation No. 24 shall submit to the Department, within 90 days of the effective date of this regulation, an application to amend the current permit and to comply with the provisions of this regulation. Any owner or operator of a non-permitted source subject to the provisions of this regulation, on and after the effective date of the regulation, shall immediately submit to the Department an application for a permit to construct, modify, reconstruct and/or operate the source.

1.6 f. Any owner or operator who owns or operates a process or operation regulated by a subsequent section of this regulation may submit to the Department proposals for alternative compliance schedules. The Department may, with the concurrence of the Administrator of the U. S. Environmental Protection Agency (U.S. EPA), approve the alternative compliance schedules if:

1.6.1 1. The proposal contains projected increments of progress which are substantially equivalent to the compliance schedules in the appropriate subsequent sections of this regulation, and,

1.6.2 2. Final compliance with emission standards is achieved not later than that stipulated in appropriate subsequent sections of this regulation, or not later than May 31, 1995, if agreed in writing by the Department.

1.7 g. In the event that the applicant's schedule of interim measures is not acceptable, the Department shall give written notice to the applicant, advising that the schedule contained in the appropriate sections of this regulation will be ordered unless an equitable compromise is agreed-upon, or a public hearing is requested. The expense of such hearing shall be borne by the applicant. The Department may order a schedule to be implemented after considering relevant testimony at the hearing, or, if no hearing is requested, issue an order on its own initiative.

1.8 h. Any alternative compliance schedule approved by the Department shall be incorporated in the State Implementation Plan (SIP).

For the purpose of this regulation, the following definitions apply:

a. “Actual emissions” means the quantity VOCs emitted from a source during a particular time period.

b. “As applied” means including any dilution solvents added before application of the coating.

c. “Basecoat” means a pigmented topcoat that is the first coat applied as part of a multistage topcoat system.

d. “Bulk gasoline plant” means a gasoline storage and distribution facility with an average daily throughput of 76,000 liters (L) (20,000 gallons [gal]) of gasoline or less on a monthly average.

e. “Bulk gasoline terminal” means a gasoline storage facility that receives gasoline from refineries, delivers gasoline to bulk gasoline plants or to commercial or retail accounts, and has a daily throughput of more than 76,000 L (20,000 gal) of gasoline on a monthly average.

f. “Capture efficiency” means the weight per unit time of VOC entering a capture system and delivered to a control device divided by the weight per unit time of total VOC generated by a source of VOC, expressed as a percentage.

g. “Capture system” means all equipment (including, but not limited to, hoods, ducts, fans, booths, ovens, dryers, etc.) that contains, collects, and transports an air pollutant to a control device.

h. “Carbon absorber” means an add-on control device that uses activated carbon to absorb VOCs from a gas stream.

i. “Carbon adsorption system" means a carbon adsorber with an inlet and outlet for exhaust gases and a system to regenerate the saturated adsorbent.

j. “Clearcoat” means a topcoat that contains no pigments or only transparent pigments and that is the final coat applied as part of a multistage topcoat system.

k. “Coating” means a material applied onto or impregnated into a substrate for protective, decorative, or functional purposes. Such materials include, but are not limited to, paints, varnishes, sealants, adhesives, inks, maskants, and temporary protective coatings.

l. “Coating unit” means a series of one or more coating applicators and any associated drying area and/or oven wherein a coating is applied, dried, and/or cured. A coating unit ends at the point where the coating is dried or cured, or prior to any subsequent application of a different coating. It is not necessary to have an oven or a flash-off area in order to be included in this definition.

m. “Continuous vapor control system” means a vapor control system that treats vapors displaced from tanks during filling on a demand basis without intermediate accumulation.

n. “Control device” means equipment (such as an incinerator or carbon adsorber) used to reduce, by destruction or removal, the amount of air pollutant(s) or pollutants in an air stream prior to discharge to the ambient air.

o. “Control system” means a combination of one or more capture system(s) or systems and control device(s) or devices working in concert to reduce discharges of pollutants to the ambient air.

p. “Day” means a period of 24 consecutive hours beginning at midnight local time, or beginning at a time consistent with a facility's operating schedule.

q. “Destruction or removal efficiency” means the amount of VOC destroyed or removed by a control device expressed as a percent of the total amount of VOC entering the device.

r. “Double block-and-bleed system” means two block valves connected in series with a bleed valve or line that can vent the line between the two block valves.

s. “Exempt compounds” means any of the compounds listed in Regulation 1, Section 2 2.0 of 7 DE Admin. Code 1101 - Definitions, "Volatile Organic Compounds," which have been determined to have negligible photochemical reactivity.

For determining compliance with emission limits, VOCs will be measured according to the procedures in Methods 25 and 25A of Appendix A of 40 CFR, Part 60, and the procedures and equations in §60.755. Where such a method also measures compounds with negligible photochemical reactivity, an owner or operator may exclude these negligibly-reactive compounds when determining compliance with an emission standard. However, the Department may require such owner or operator, as a precondition to excluding these compounds for purposes of determining compliance, to provide monitoring methods and monitoring results demonstrating, to the satisfaction of the Department, the amount of negligibly-reactive compounds in the sources emissions.

In addition to the procedures for requesting a satisfactory compliance determination, where the Department proposes to allow the use of a test method for excluding negligibly-reactive compounds that is different or not specified in the approved SIP, such change shall be submitted to the U.S. EPA for approval as part of a SIP revision.

t. “External floating roof” means a cover over an open-top storage tank consisting of a double deck or pontoon single deck that rests upon and is supported by the volatile organic liquid being contained and is equipped with a closure seal or seals to close the space between the roof edge and tank shell.

u. “Facility” means all of the pollutant-emitting activities, excluding pollutant-emitting activities from mobile sources that are located on one (1) or more contiguous or adjacent properties, and are under the control of the same person (or person under common control).

v. “First attempt at repair” means to take rapid action for the purpose of stopping or reducing leakage of organic material to the atmosphere using best practices.

w. “Flash-off area” means the space between the coating application area and the oven.

x. “Gasoline tank truck” means a delivery tank truck used at bulk gasoline plants, bulk gasoline terminals, or gasoline dispensing facilities that is loading or unloading gasoline or that has loaded or unloaded gasoline on the immediately previous load.

y. “Gloss flattener” means a low-gloss coating that is formulated to eliminate glare on the interior surfaces of a vehicle for safety purposes, as specified under the U.S. Department of Transportation Motor Vehicle Safety Standards.

z. “Heavy-duty truck” means any motor vehicle rated at greater than 3,864 kg (8,500 lb) gross weight designed primarily to transport property.

aa. “Incinerator” means a combustion apparatus in which solid, semisolid, liquid, or gaseous combustible wastes are ignited and burned and from which the solid and gaseous residues contain little or no combustible material.

bb. “Intermittent vapor control system” means a vapor control system that employs an intermediate vapor holder to accumulate vapors displaced from tanks during filling. The control device treats the accumulated vapors only during automatically controlled cycles.

cc. “Internal Floating Roof” means a cover or roof in a fixed-roof tank that rests upon or is floated upon, the liquid being contained, and is equipped with a closure seal or seals to close the space between the roof edge and the tank shell.

dd. “Knife coating” means the application of a coating material to a substrate by means of drawing the substrate beneath a knife that spreads the coating evenly over the full width of the substrate.

ee. “Leak” means a VOC emission indicated by an instrument calibrated according to Method 21 of 40 CFR, Part 60, Appendix A, using zero air (less than 10 parts per million [ppm] of hydrocarbon in air) and a mixture of methane or n-hexane and air at a concentration of about, but less than, 10,000 ppm methane or n-hexane.

ff. “Lease custody transfer” means the transfer of produced crude oil or condensate, after processing and/or treating in the producing operations, from storage tanks or automatic transfer facilities to pipelines or any other forms of transportation.

gg. “Liquid-mounted seal” means a primary seal mounted in continuous contact with the liquid between the tank wall and the floating roof around the circumference of the tank.

hh. “Loading rack” means an aggregation or combination of gasoline loading equipment arranged so that all loading outlets in the combination can be connected to a tank truck or trailer parked in a specified loading space.

ii. “Lower explosive limit” (LEL) means the concentration of a compound in air below which a flame will not propagate if the mixture is ignited.

jj. “Maximum theoretical emissions” means the quantity of VOC that theoretically could be emitted by a source without control devices based on the design capacity or maximum production capacity of the source and 8,760 hours of operation per year. The design capacity or maximum production capacity includes use of coatings and inks with the highest VOC content used in practice by the source for the 2 two preceding years.

kk. “Maximum true vapor pressure” means the equilibrium partial pressure exerted by a stored liquid at the temperature equal to:

1. for liquids stored above or below the ambient temperature, the highest calendar-month average of the liquid storage temperature, or

2. for liquids stored at the ambient temperature, the local maximum monthly average temperature as reported by the National Weather Service. This pressure shall be determined by one of the following:

i. In accordance with methods described in American Petroleum Institute Bulletin 2517, "Evaporation Loss From External Floating Roof Tanks."

ii. By using standard reference texts.

iii. By ASTM D2879-83.

iv. By any other method approved by the Department as part of the State Implementation Plan (SIP) Revision.

ll. “Multicomponent coating” means a coating which is packaged in two or more parts, which parts are combined before application, and where a coreactant from one part of the coating chemically reacts, at ambient conditions, with a coreactant from another part of the coating.

mm. “Open-ended valve or line” means any valve, except safety relief valves, having one side of the valve seat in contact with process fluid and one side open to the atmosphere, either directly or through open piping.

nn. “Organic compound” means any carbon-containing chemical compound excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate.

oo. “Oven” means a chamber which is used to bake, cure, polymerize, and/or dry a coating.

pp. “Overall emission reduction efficiency” means the weight per unit time of VOC removed or destroyed by a control device divided by the weight per unit time of VOC generated by a source, expressed as a percentage. The overall emission reduction efficiency can also be calculated as the product of the capture efficiency and the control device destruction or removal efficiency.

qq. “Owner or Operator” means any person who owns, leases, controls, operates or supervises a facility, a source, or air pollution control or monitoring equipment.

rr. “Person” means any individual, partnership, copartnership, firm, company, corporation, association, joint stock company, trust, estate, political subdivision, or any other legal entity, or their legal representative, agent, or assigns.

ss. “Petroleum” means the crude oil removed from the earth and the oils derived from tar sands, shale and coal.

tt. “Petroleum Liquid” means petroleum condensate, and any finished or intermediate products manufactured in a petroleum refinery.

uu. “Plastisol” means a coating made of a mixture of finely divided resin and a plasticizer. Plastisol is applied as a thick gel that solidifies when heated.

vv. “Press-Ready Ink” means the ink, as applied to the substrate, after all solvents and diluents have been added.

ww. “Pressure release” means the emission of materials resulting from system pressure being greater than set pressure of the pressure relief device.

xx. “Primer” means any coating applied prior to the application of a topcoat or color coat for the purposes of surface preparation, corrosion resistance, adhesion, and color uniformity.

yy. “Process unit shutdown” means a work practice or operational procedure that stops production from a process unit or part of a process unit. An unscheduled work practice or operational procedure that stops production from a process unit or part of a process unit for less than 24 hours is not a process unit shutdown. The use of spare equipment and technically feasible bypassing of equipment without stopping production are not process unit shutdowns.

zz. “Reid vapor pressure” means the absolute vapor pressure of volatile crude oil and volatile nonviscous petroleum liquids, except liquified petroleum gases, as determined by ASTM D323-82.

aaa. “Repaired” means that equipment is adjusted, or otherwise altered, in order to eliminate a leak as indicated by one of the following: an instrument reading of 10,000 ppm or greater, indication of liquids dripping, or indication by a sensor that a seal or barrier fluid system has failed.

bbb. “Roll coating” means the application of a coating material to a moving substrate by means of hard rubber, elastomeric, or metal rolls.

ccc. “Rotogravure coating” means the application of a coating material to a substrate by means of a roll coating technique in which the pattern to be applied is recessed relative to the non-image area, and the coating material is picked up in these recessed areas and is transferred to the substrate.

ddd. “Shutdown” means the cessation of operation of a facility or of its emission control or emission monitoring equipment.

eee. “Source” means any building, structure, equipment (excluding mobile equipment temporarily in place), or installation that directly or indirectly releases or discharges, or has the potential to release or discharge, VOCs into the atmosphere.

fff. “Stage I Vapor Recovery System” means the control of gasoline vapor from any delivery vessel into any stationary storage vessel, where the vapor displaced by the liquid gasoline is returned to the delivery vessel and transported to the refinery.

gig. “Stage II Vapor Recovery System” means a system that controls the emissions of gasoline vapor at the vehicle fill-pipe, where the vapor is captured and returned to a vapor-tight storage tank, or is destroyed; which achieves an overall control efficiency of at least 95%.

hhh. “Standard conditions” means a temperature of 20^oC (68^oF) and pressure of 760 mm Hg (29.92 in. Hg).

iii. “Startup” means the setting in operation of a source or of its emission control or emission monitoring equipment.

jjj. “Storage Vessel” means each tank, reservoir or container used for the storage of Volatile Organic Liquids, but does not include:

1. Frames, housing, auxiliary supports or other components that are not directly involved in the containment of liquids or vapors; or

2. Subsurface caverns or porous rock reservoirs.

kkk. “Submerged fill” means the method of filling a delivery vessel or storage vessel where product enters within 150 millimeters (mm) (5.9 inches [in.]) of the bottom of the delivery or storage vessel. Bottom filling of delivery and storage vessels is included in this definition.

lll. “Substrate” means the surface onto which a coating is applied or into which a coating is impregnated.

mmm. “Throughput” means the amount of gasoline dispensed at a gasoline dispensing facility during a calendar month after November 15, 1990.

nnn. “Transfer efficiency” means the ratio of the amount of coating solids adhering to the object being coated to the total amount of coating solids used in the application process, expressed as a percentage.

ooo. “Vapor collection system” means all piping, seals, hoses, connections, pressure-vacuum vents, and other equipment between the gasoline tank truck and the vapor processing unit and/or the storage tanks and vapor holder.

ppp. “Vapor control system” means a system that limits or prevents release to the atmosphere of organic compounds in the vapors displaced from a tank during the transfer of gasoline.

qqq. “Vapor-mounted seal” means a primary seal mounted so there is an annular vapor space underneath the seal. The annular vapor space is bounded by the bottom of the primary seal, the tank wall, the liquid surface and the floating roof.

rrr. “Vapor recovery system” means a vapor-gathering system capable of collecting VOC vapors and gases emitted during the operation of any transfer, storage, or process equipment.

sss. “Vapor-tight” means equipment that allows no loss of vapors. Compliance with vapor-tight requirements can be determined by checking to ensure that the concentration at a potential leak source is not equal to or greater than 100% of the LEL when measured with a combustible gas detector, calibrated with propane, at a distance of 2.54 centimeters (cm) (1 inch)from the source.

ttt. “Vapor-tight gasoline tank truck” means a gasoline tank truck that has demonstrated within the 12 preceding months that its product delivery tank will sustain a pressure change of not more than 75 mm (3.0 in.) of water within 5 five minutes (min) after it is pressurized to 450 mm (18 in.) of water; or when evacuated to 150 mm (5.9 in.) of water, the same tank will sustain a pressure change of not more than 75 mm (3.0 in.) of water within 5 min. This capability is to be demonstrated using the test procedures specified in Method 27 of Appendix A of 40 CFR, Part 60 (July 1, 1992).

uuu. “Volatile Organic Liquid” (VOL) means any organic liquid which can emit any Volatile Organic Compound into the atmosphere (see definition of "Volatile Organic Compound" of this regulation).

vvv. “Volatile Organic Compound” (VOC) means any carbon-containing compound excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates and ammonium carbonate, which participates in atmospheric photochemical reactions. This includes any organic compounds other than those defined as "Exempt Compounds", which have been determined to have negligible photochemical reactivity (see definition of "Exempt Compounds" of this regulation). In addition to the procedures for requesting a satisfactory compliance demonstration, where the Department proposes to allow the use of a test method for excluding negligibly reactive compounds that is different from or not specified in the approved SIP, such change shall be submitted to the Environmental Protection Agency (U.S. EPA) for approval as part of a SIP Revision.

www. “Web coating line” means all of the coating applicator(s) or applicators, drying area(s) or areas, or oven(s) or ovens, located between an unwind station and a rewind station, that are used to apply coating onto a continuous strip of substrate (the web). A web coating line need not have a drying oven.

3.1 a. All existing, new, reconstructed and modified sources shall meet all applicable provisions of this regulation.

3.2 b. Nothing in this regulation shall be construed to exempt new, reconstructed or modified sources from meeting any other applicable Department or federal rules, including New Source Review requirements.

3.3 c. This regulation does not apply to any equipment at a facility used exclusively for chemical or physical analysis or determination of product quality and commercial acceptance provided the operation of the equipment is not an integral part of the production process and the total actual emissions from all such equipment at the facility do not exceed 204 kilograms (kg) (450 pounds [lb]) in any calendar month. Any facility claiming exemption from the provisions 3.3 of this regulation under paragraph (c) shall comply with the provisions of Paragraph (e) 3.5 of this regulation.

3.4 d.

3.4.1 1. Any facility that becomes or is currently subject to the provisions of this regulation by exceeding an applicability threshold will remain subject to these provisions, even if its throughput or emissions later fall below the applicability threshold, except as provided in Paragraph (g) 3.7 of this regulation.

3.4.2 2. Any facility that is currently subject to a state or federal rule promulgated pursuant to the Clean Air Act Amendments of 1977 by exceeding an applicability threshold is and will remain subject to these provisions, even if its throughput or emissions have fallen or later fall below the applicability threshold.

3.5 e. Any facility that claims exemption from the provisions of this regulation by reason of meeting the conditions in paragraph (c) 3.3 of this Section regulation shall maintain the following annual records in a readily accessible location for at least 5 years and shall make those records available to the Department upon verbal or written request:

3.5.1 1. Records to document the purpose of the equipment for which the exemption is claimed.

3.5.2 2. Records to document the amount of each volatile organic compound (VOC)-containing material used in the equipment each calendar month and the VOC content of each material such that emissions can be determined for each calendar month.

3.6 f. The owner or operator of a facility or source subject to any control requirement of this regulation may comply with an alternative control plan that has been approved by the Department and the U.S. EPA.

3.7 g. The owner or operator of a facility or source subject to this regulation may petition the Department for exemption from the requirements of this regulation upon a showing that such facility or source no longer has the potential to emit Volatile Organic Compounds (VOCs). Any exemption granted shall be embodied in a Consent Order which shall contain terms and conditions necessary to ensure that no Volatile Organic Compounds (VOCs) may be emitted from the facility or source. For federal enforcement purposes, such exemption shall not be effective until approved by the U.S. EPA.

4.1 a. To establish the records required under this Section 4.0 of this regulation, the volatile organic compound (VOC) content of each coating, as applied, and the efficiency of each capture system and control device shall be determined by the applicable test methods and procedures specified in Appendix B and Appendix D of this regulation.

4.2 b. Requirements for coating sources exempt from emission limitations. Any owner or operator of a coating unit, line, or operation that is exempt from the emission limitations of Section 10 through Section 23 10.0 through 23.0 of this regulation because combined VOC emissions from all coating units, lines, and operations at the facility are below the applicability threshold specified in the individual sections of this regulation, before the application of capture systems and control devices, shall comply with the following for each section of this regulation from which the owner or operator claims an exemption:

4.2.1 1. Certification. By November 15, 1993, the owner or operator of a facility referenced in paragraph (b) 4.2 of this Section regulation shall certify to the Department that the facility is exempt from emission limitations by providing all of the following:

4.2.1.1 i. The name and location of the facility.

4.2.1.2 ii. The address and telephone number of the person responsible for the facility.

4.2.1.3 iii. A declaration that the facility is exempt from the emission limitations of Section 10 through Section 23 10.0 through 23.0 of this regulation because combined VOC emissions from all coating units, lines, and operations at the facility that are covered by an individual section of this regulation are below the appropriate applicability threshold before the application of capture systems and control devices.

4.2.1.4 iv. Calculations of the daily-weighted average that demonstrate that the combined VOC emissions from all coating units, lines, and operations at the facility that are covered by an individual section of this regulation for a day representative of current maximum production levels are less than 6.8 kilograms (kg) (15 pounds [lb]) before the application of capture systems and control devices. The following equation shall be used to calculate total VOC emissions for that day:

(4-1)

where:

T = Total VOC emissions from coating units, lines, and operations at the facility before the application of capture systems and control devices in units of kg/day (lb/day).

n = Number of different coatings applied on each coating unit, each coating line, or each operation at the facility.

i = Subscript denoting an individual coating.

A_i = Mass of VOC per volume of coating (i) (excluding water and exempt compounds), as applied, used at the facility in units of kilograms VOC per liter (kg VOC/L) (pounds VOC per gallon [lb VOC/gal]).

B_i = Volume of coating (i) (excluding water and exempt compounds), as applied, used at the facility in units of liters per day (L/day) (gallons per day [gal/day]). The instrument or method by which the owner or operator accurately measured or calculated the volume of each coating, as applied, used at the facility shall be described in the certification to the Department.

4.2.2 2. Recordkeeping. On and after November 15, 1993, the owner or operator of a facility referenced in paragraph (b) 4.2 of this Section regulation shall collect and record all of the following information each day and maintain the information at the facility for a period of 5 years:

4.2.2.1 i. The name and identification number of each coating, as applied.

4.2.2.2 ii. The mass of VOC per volume (excluding water and exempt compounds) and the volume of coating (i) (excluding water and exempt compounds), as applied, used each day.

4.2.2.3 iii. The total VOC emissions at the facility, as calculated using the equation under paragraph (b)(l)(iv) 4.2.1.4 of this Section regulation.

4.2.3 3. Reporting. On and after November 15, 1993, the owner or operator of a facility referenced in paragraph (b) 4.2 of this Section regulation shall notify the Department of any record showing that combined VOC emissions from all coating units, lines, and operations at the coating facility exceed 6.8 kg (15 lb) on any day, before the application of capture systems and control devices. A copy of such record shall be sent to the Department within 45 calendar days after the exceedance occurs. This reporting requirement is in addition to any other exceedance reporting requirements mandated by the State of Delaware.

4.3 c. Requirements for coating sources using complying coatings. Any owner or operator of a coating unit, line, or operation subject to the limitations of Sections 10 through 12 10.0 through 12.0 or of Section 13(c)(1) 13.3.1 or Section 14 through Section 23 14.0 through 23.0 of this regulation and complying by means of the use of complying coatings shall comply with the following:

4.3.1 1. Certification. By November 15, 1993, or upon startup of a new coating unit, line, or operation, or upon changing the method of compliance for an existing subject coating unit, line, or operation from daily-weighted averaging or control devices to the use of complying coatings, the owner or operator of a coating unit, line, or operation referenced in paragraph (c) 4.3 of this Section regulation shall certify to the Department that the coating unit, line, or operation is or will be in compliance with the requirements of the applicable section of this regulation on and after November 15, 1993, or on and after the initial startup date. Such certification shall include:

4.3.1.1 i. The name and location of the facility.

4.3.1.2 ii. The address and telephone number of the person responsible for the facility.

4.3.1.3 iii. Identification of subject sources.

4.3.1.4 iv. The name and identification number of each coating, as applied, on each coating unit, line, or operation.

4.3.1.5 v. The mass of VOC per volume (excluding water and exempt compounds) and the volume of each coating (excluding water and exempt compounds), as applied per day.

4.3.1.6 vi. The time at which the facility's "day" begins if a time other than midnight local time is used to define a "day."

4.3.2 2. Recordkeeping. On and after November 15, 1993, or on and after the initial startup date, the owner or operator of a coating unit, line, or operation referenced in paragraph (c) 4.3 of this Section regulation and complying by the use of complying coatings shall collect and record all of the following information each day for each coating unit, line, or operation and maintain the information at the facility for a period of 5 five years:

4.3.2.1 i. The name and identification number of each coating, as applied, on each coating unit, line, or operation.

4.3.2.2 ii. The mass of VOC per volume of each coating (excluding water and exempt compounds), as applied, used each day on each coating unit, line, or operation.

4.3.2.3 iii. The volume of each coating applied each day on each coating unit line or operation.

4.3.3 3. Reporting. On and after November 15, 1993, the owner or operator of a subject coating unit, line, or operation referenced in paragraph (c) 4.3 of this Section regulation shall notify the Department in either of the following instances:

4.3.3.1 i. Any record showing use of any non-complying coatings shall be reported by sending a copy of such record to the Department within 45 calendar days following that use.

4.3.3.2 ii. At least 30 calendar days before changing the method of compliance from the use of complying coatings to daily-weighted averaging or control devices, the owner or operator shall comply with all requirements of paragraph (d)(1) or (e)(1) 4.4.1 or 4.5.1 of this Section regulation, respectively, as well as Regulation No. 2 7 DE Admin. Code 1102. Upon changing the method of compliance from the use of complying coatings to daily-weighted averaging or control devices, the owner or operator shall comply with all requirements of the section of this regulation applicable to the coating unit, line, or operation referenced in paragraph (c) 4.3 of this Section regulation.

4.4 d. Requirements for coating sources using daily-weighted averaging. Any owner or operator of a coating unit, line, or operation subject to the limitations of Sections 10 through 12 10.0 through 12.0 or Section 13(c)(1) 13.3.1 or Section 14 through Section 23 14.0 through 23.0 of this regulation and complying by means of daily-weighted averaging on that unit, line, or operation shall comply with the following:

4.4.1 1. Certification. By November 15, 1993, or upon startup of a new coating unit, line, or operation, or upon changing the method of compliance for an existing subject coating unit, line, or operation from the use of complying coatings or control devices to daily-weighted averaging, the owner or operator of the subject coating unit, line, or operation shall certify to the Department that the coating unit, line, or operation is or will be in compliance with paragraph (d) 4.4 of this Section regulation on and after November 15, 1993, or on and after the initial startup date. Such certification shall include:

4.4.1.1 i. The name and location of the facility.

4.4.1.2 ii. The address and telephone number of the person responsible for the facility.

4.4.1.3 iii. Identification of subject sources.

4.4.1.4 iv. The name and identification number of each coating unit, line, or operation that will comply by means of daily-weighted averaging.

4.4.1.5 v. The instrument or method by which the owner or operator will accurately measure or calculate the volume of each coating (excluding water and exempt compounds), as applied, used each day on each coating unit, line, or operation.

4.4.1.6 vi. The method by which the owner or operator will create and maintain records each day as required in paragraph (d)(2) 4.4.2 of this Section regulation.

4.4.1.7 vii. Calculation of the daily-weighted average, using the procedure in 1.0 of Appendix C (a) of this regulation, for a day representative of current or projected maximum production levels.

4.4.1.8 viii. The time at which the facility's "day" begins if a time other than midnight local time is used to define a "day."

4.4.2 2. Recordkeeping. On and after November 15, 1993, or on and after the initial startup date, the owner or operator of a coating unit, line, or operation referenced in paragraph (d) 4.4 of this Section regulation and complying by means of daily-weighted averaging shall collect and record all of the following information each day for each coating unit, line, or operation and maintain the information at the facility for a period of 5 five years:

4.4.2.1 i. The name and identification number of each coating, as applied, on each coating unit, line, or operation.

4.4.2.2 ii. The mass of VOC per volume (excluding water and exempt compounds) and the volume of each coating (excluding water and exempt compounds), as applied, used each day on each coating unit, line, or operation.

4.4.2.3 iii. The daily-weighted average VOC content of all coatings, as applied, on each coating unit, line, or operation calculated according to the procedure in 1.0 of Appendix (a) C of this regulation.

4.4.3 3. Reporting. On and after November 15, 1993, the owner or operator of a subject coating unit, line, or operation referenced in paragraph (d) 4.4 of this Section regulation shall notify the Department in either of the following instances:

4.4.3.1 i. Any record showing noncompliance with the applicable daily-weighted average requirements shall be reported by sending a copy of the record to the Department within 45 calendar days following the occurrence.

4.4.3.2 ii. At least 30 calendar days before changing the method of compliance from daily-weighted averaging to the use of complying coatings or control devices, the owner or operator shall comply with all requirements of paragraph (c)(1) or (e)(1) 4.3.1 or 4.5.1 of this Section regulation, respectively, as well as Regulation No. 2 7 DE Admin. Code 1102. Upon changing the method of compliance from daily-weighted averaging to the use of complying coatings or control devices, the owner or operator shall comply with all requirements of the Ssection of this regulation applicable to the coating unit, line, or operation referenced in paragraph (d) 4.4 of this Section regulation.

4.5 e. Requirements for coating sources using control devices. Any owner or operator of a coating unit, line, or operation subject to the limitations of Section 10 through Section 23 10.0 through 23.0 of this regulation and complying by means of control devices shall comply with the following:

4.5.1 1. Testing of control equipment. By November 15, 1993, or upon startup of a new coating unit, line, or operation, or upon changing the method of compliance for an existing coating unit, line, or operation from the use of complying coatings or daily-weighted averaging to control devices, the owner or operator of the subject coating unit, line, or operation shall perform a compliance test. Testing shall be performed within ninety (90) 90 days of startup, and pursuant to the procedures in Appendix A through Appendix D of this regulation. The owner or operator of the subject coating unit, line, or operation shall submit to the Department the results of all tests and calculations necessary to demonstrate that the subject coating unit, line, or operation is or will be in compliance with the applicable section of this regulation on and after November 15, 1993, or on and after the initial startup date.

4.5.2 2. Recordkeeping. On and after November 15, 1993, or on and after the initial startup date, the owner or operator of a coating unit, line, or operation referenced in paragraph (e) 4.5 of this Section regulation shall collect and record all of the following information each day for each coating unit, line, or operation and maintain the information at the facility for a period of 5 five years:

4.5.2.1 i. The name and identification number of each coating used on each coating unit, line, or operation.

4.5.2.2 ii. The mass of VOC per unit volume of coating solids, as applied, the volume solids content, as applied, and the volume, as applied, of each coating used each day on each coating unit, line, or operation.

4.5.2.3 iii. The maximum VOC content (mass of VOC per unit volume of coating solids, as applied) or the daily-weighted average VOC content (mass of VOC per unit volume of coating solids, as applied) of the coatings used each day on each coating unit, line, or operation.

4.5.2.4 iv. The required overall emission reduction efficiency for each day for each coating unit, line, or operation as determined in Section 10(e)(1)(iii), Section 11(d), Section 12(e)(1)(iii), Section 13(e)(1)(iii), Section 14(e)(1)(iii), Section 15(e)(1)(iii), Section 16(e)(1)(iii), Section 17(e)(1)(iii), Section 18(e)(1)(iii), Section 19(e)(1)(iii), Section 20(e)(1)(iii), Section 21(e)(1)(iii), Section 22(e)(1)(iii), Section 23(e)(1)(iii) 10.5.1.3, 11.4, 12.5.1.3, 13.5.1.3, 14.5.1.3, 15.5.1.3, 16.5.1.3, 17.5.1.3, 18.5.1.3, 19.5.1.3, 20.5.1.3, 21.5.1.3, 22.5.1.3, 23.5.1.3 of this regulation.

4.5.2.5 v. The actual overall emission reduction efficiency achieved for each day for each coating unit, line, or operation as determined in 3.0 of Appendix (c) D of this regulation.

4.5.2.6 vi. Control device monitoring data.

4.5.2.7 vii. A log of operating time for the capture system, control device, monitoring equipment, and the associated coating unit, line, or operation.

4.5.2.8 viii. A maintenance log for the capture system, control device, and monitoring equipment detailing all routine and non-routine maintenance performed including dates and duration of any outages.

4.5.2.9 ix. For thermal incinerators, all 3-hour periods of operation in which the average combustion temperature was more than 28°C (50°F) below the average combustion temperature during the most recent performance test that demonstrated that the facility was in compliance. The combustion chamber set-point shall be no less than that during the most recent performance test that demonstrated that the facility was in compliance.

4.5.2.10 x. For catalytic incinerators, all 3-hour periods of operation in which the average temperature of the process vent stream immediately before the catalyst bed is more than 28°C (82°F) below the average temperature of the process vent stream immediately before the catalyst bed during the most recent performance test that demonstrated that the facility was in compliance. The set-point for the process vent stream immediately before the catalyst bed shall be no less than that during the most recent performance test that demonstrated that the facility was in compliance.

4.5.2.11 xi. For carbon adsorbers, all 3 three-hour periods of operation during which either the average VOC concentration or the reading of organics in the exhaust gases is more than 20% percent greater than the average exhaust gas concentration or reading measured by the organics monitoring device during the most recent determination of the recovery efficiency of the carbon adsorber that demonstrated that the facility was in compliance.

4.5.3 3. Reporting. On and after November 15, 1993, the owner or operator of a subject coating unit, line, or operation referenced in paragraph (e) 4.5 of this Section regulation shall notify the Department in either of the following instances:

4.5.3.1 i. Any record showing noncompliance with the applicable requirements for control devices shall be reported by sending a copy of the record to the Department within 45 calendar days following the occurrence.

4.5.3.2 ii. At least 30 calendar days before changing the method of compliance from control devices to the use of complying coatings or daily-weighted averaging, the owner or operator shall comply with all requirements of paragraph (c)(1) 4.3.1 or (d)(1) 4.4.1 of this Section regulation, respectively, as well as Regulation No. 2 7 DE Admin. Code 1102. Upon changing the method of compliance from control devices to the use of complying coatings or daily-weighted averaging, the owner or operator shall comply with all requirements of the section of this regulation applicable to the coating unit, line, or operation referenced in paragraph (e) 4.5 of this Section regulation.

5.1 a. Initial compliance certification. The owner or operator of any facility containing sources subject to this Section 5.0 of this regulation shall submit to the Department an initial compliance certification by November 15, 1993. The owner or operator of any new facility containing sources that become subject to this Section 5.0 of this regulation after November 15, 1992 shall submit an initial compliance certification immediately upon startup of the facility.

5.1.1 1. The initial compliance certification shall provide at a minimum the following information:

5.1.1.1 i. The name and location of the facility.

5.1.1.2 ii. The address and telephone number of the person responsible for the facility.

5.1.1.3 iii. Identification of subject sources.

5.1.2 2. For each subject source, the initial compliance certification shall also provide at a minimum:

5.1.2.1 i. The applicable emission limitation, equipment specification, or work practice.

5.1.2.2 ii. The method of compliance.

5.1.2.3 iii. For each source subject to numerical emission limitations of this regulation, the estimated emissions without control.

5.1.2.4 iv. The control system(s) or systems in use.

5.1.2.5 v. The design performance efficiency of the control system.

5.1.2.6 vi. For each source subject to numerical emission limitations of this regulation, the estimated emissions after control.

5.1.2.7 vii. Certification that each subject source at the facility is in compliance with the applicable emission limitation, equipment specification, or work practice.

5.1.2.8 viii. The time at which the facility's "day" begins if a time other than midnight local time is used to define a "day."

5.2 b. Reports of excess emissions. The owner or operator of any facility containing sources subject to this Section 5.0 of this regulation shall, for each occurrence of excess emissions, within 30 calendar days of becoming aware of such occurrence, supply the Department with the following information, in addition to complying with any other reporting requirements mandated by the State of Delaware:

5.2.1 1. The name and location of the facility.

5.2.2 2. The subject sources that caused the excess emissions.

5.2.3 3. The time and date of first observation of the excess emissions.

5.2.4 4. The cause and expected duration of the excess emissions.

5.2.5 5. For sources subject to numerical emission limitations, the estimated rate of emissions (expressed in the units of the applicable emission limitation) and the operating data and calculations used in determining the magnitude of the excess emissions.

5.2.6 6. The proposed corrective actions and schedule to correct the conditions causing the excess emissions.

5.3 c. Requirements for sources using control devices.

5.3.1 1. Testing of control equipment. By November 15, 1993, or upon startup of a new source, or upon changing the method of compliance for an existing source, the owner or operator of the subject source shall perform all tests and submit to the Department the results of all tests and calculations necessary to demonstrate that the subject source will be in compliance with the applicable section of this regulation on and after November 15, 1993, or on and after the initial startup date.

5.3.2 2. Recordkeeping.

5.3.2.1 i. Each owner or operator of a source subject to this Section 5.0 of this regulation shall maintain up-to-date, readily accessible continuous records of any equipment operating parameters specified to be monitored in the applicable section of this regulation as well as up-to-date, readily accessible records of periods of operation during which the parameter boundaries established during the most recent performance test are exceeded. These records shall be maintained for at least 5 five years. The Department may at any time require a report of these data. Periods of operation during which the parameter boundaries established during the most recent performance tests are exceeded are defined as follows:

5.3.2.1.1 A. For thermal incinerators, all 3 three-hour periods of operation in which the average combustion temperature was more than 28°C (50°F) below the average combustion temperature during the most recent performance test that demonstrated that the facility was in compliance. The combustion chamber set-point shall be no less than that during the most recent performance test that demonstrated that the facility was in compliance.

5.3.2.1.2 B. For catalytic incinerators, all 3 three-hour periods of operation in which the average temperature of the process vent stream immediately before the catalyst bed is more than 28°C (50°F) below the average temperature of the process vent stream immediately before the catalyst bed during the most recent performance test that demonstrated that the facility was in compliance. The set-point for the process vent stream immediately before the catalyst bed shall be no less than that during the most recent performance test that demonstrated that the facility was in compliance.

5.3.2.1.3 C. For carbon adsorbers, all 3 three-hour periods of operation during which either the average VOC concentration or the reading of organics in the exhaust gases is more than 20% percent greater than the average exhaust gas concentration or reading measured by the organics monitoring device during the most recent determination of the recovery efficiency of the carbon adsorber that demonstrated that the facility was in compliance.

5.3.2.2 ii. A log of operating time for the capture system, control device, monitoring equipment, and the associated source.

5.3.2.3 iii. A maintenance log for the capture system, control device, and monitoring equipment detailing all routine and non-routine maintenance performed including dates and duration of any outages.

Each owner or operator of a source subject to this regulation shall maintain all records necessary for determining compliance with this regulation at the facility for a period of 5 five years.

7.1 a. No owner or operator subject to this regulation may build, erect, install, or use any article, machine, equipment, process, or other method the use of which conceals emissions that would otherwise constitute non-compliance with an applicable section of this regulation.

7.2 b. Paragraph (a) of this Section 7.1 of this regulation includes, but is not limited to, the use of gaseous diluents to achieve compliance, and the piecemeal carrying out of an operation to avoid coverage by a section of this regulation that applies only to operations larger than a specified size.

7.3 c. No owner or operator of a facility subject to this regulation shall discharge or dispose of VOCs or material containing VOCs to surface impoundments, pits, wastewater treatment facilities or sewers for the purpose of circumventing any provision or requirement of this regulation.

8.1 a. No owner or operator of a facility subject to this regulation may cause, allow, or permit the disposal of more than 5 five kilograms (kg) (11 pounds [lb]) of any VOC, or of any materials containing more than 5 five kg (11 lb) of any VOCs, at that facility in any 1 one day in a manner that would permit the evaporation of VOC into the ambient air. This provision does not apply to:

8.1.1 1. Any VOC or material containing VOC emitted from a regulated entity that is subject to a VOC standard under this regulation.

8.1.2 2. Coating sources that are exempt from the emission limitations of Section 10 through Section 23 10.0 through 23.0 of this regulation.

8.1.3 3. Waste paint (sludge) handling systems, water treatment systems, and other similar operations at coating facilities using complying coatings.

8.1.4 4. Any VOC or material containing VOCs used during process maintenance turnarounds for cleaning purposes, provided that the provisions of 8(c), (d) and (e) 8.3, 8.4 and 8.5 are followed.

8.2 b. Paragraph (a) of this Section 8.2 of this regulation includes, but is not limited to, the disposal of VOC from VOC control devices.

8.3 c. No owner or operator of a facility subject to this regulation shall use open containers for the storage or disposal of cloth or paper impregnated with VOCs that are used for surface preparation, cleanup, or coating removal. Containers for the storage or disposal of cloth or paper impregnated with VOCs shall be kept closed, except when adding or removing material.

8.4 d. No owner or operator of a facility subject to this regulation shall store in open containers spent or fresh VOC to be used for surface preparation, cleanup or coating removal. Containers for the storage of spent or fresh VOCs shall be kept closed, except when adding or removing material.

8.5 e. No owner or operator of a facility subject to this regulation shall use VOC for the cleanup of spray equipment unless equipment is used to collect the cleaning compounds and to minimize their evaporation to the atmosphere.

9.1 a. Compliance with the provisions of this regulation is required immediately upon promulgation.

9.2 b. Permits. After the effective date of this regulation, no owner or operator shall construct, modify or operate any source subject to this regulation without first obtaining a permit for such construction, modification or operation pursuant to the provisions of Regulation No. 2 7 DE Admin. Code 1102.

9.3 c. Compliance Programs and Schedules. For sources as a result of this regulation that are required to make major process changes and/or major capital expenditures, as determined by the Department, an acceptable program to comply with this regulation shall be developed and submitted to the Department by the owner and/or operator of such source within one hundred eighty (180) 180 days of the effective date of the regulation. The program shall include the dates for ordering, receiving, installation and startup of necessary equipment. All such programs shall contain a schedule and timetable for compliance certification, including increments of progress which will require compliance with the applicable requirements as expeditiously as practicable, but not later than the date specified in the applicable requirement. [Note: For federal purposes and for federal enforcement, no such program approved by the Department shall be federally-approved pursuant to the Clean Air Act until the Administrator of the U.S. EPA determines that such program was approved in accordance with these requirements, or within the applicable provisions of the Federal Clean Air Act, and any such program approved by the Department shall cease to be federally approved upon a determination by the Administrator of the U.S. EPA that it was not issued in accordance with the applicable provisions of the Federal Clean Air Act].

9.4 d. Enforceability. For the purpose of federal enforceability of the provisions of this regulation, references to the Department shall also mean the Administrator of the U.S. EPA.

10.1 a. Applicability

10.1.1 1. Except as provided for in (a)(2) and (a)(3) 10.1.2 and 10.1.3 of this regulation, this Section 10.0 of this regulation applies to any owner or operator of any aerospace manufacturing or rework facility that conducts any of the following operation(s) or operations:

10.1.1.1 i. hand-wipe cleaning;

10.1.1.2 ii. spray gun cleaning;

10.1.1.3 iii. flush cleaning;

10.1.1.4 iv. primer, topcoat, self-priming topcoat, and specialty coating application;

10.1.1.5 v. the depainting of the outer surface of aerospace vehicles (except for depainting parts or units normally removed during depainting);

10.1.1.6 vi. Type I or Type II chemical milling maskant application; and

10.1.1.7 vii. VOC handling and storage.

10.1.2 2. Except for the requirements in paragraph (c)(8) 10.3.8 of this regualtion, this Section 10.0 of this regulation does not apply to the following operations in any aerospace manufacturing or rework facility:

10.1.2.1 i. Chemical milling;

10.1.2.2 ii. Metal finishing;

10.1.2.3 iii. Electrodeposition (except for the electrodeposition of paints); and

10.1.2.4 iv. Composite processing operations (except for cleaning and coating of composite parts or components that become part of an Aerospace vehicle or component as well as composite tooling that comes in contact with such composite parts or components prior to cure).

10.1.3 3. The requirements of this Section 10.0 of this regulation do not apply to aerospace manufacturing or rework facilities whose plant-wide, actual emissions from the operations in paragraph (a)(1) without control devices are less than 6.8 kilograms (kg) (15 pounds [lbs]) of volatile organic compounds (VOCs) per day.

10.1.4 4. Existing sources affected by this Section 10.0 of this regulation shall comply with the provisions of this Section 10.0 of this regulation on and after the effective date of this Section 10.0 of this regulation, except for the requirements of paragraph (c)(6)(ii) and (c)(7) 10.3.6.2 and 10.3.7 of this regulation. Existing sources affected by this Section 10.0 of this regulation shall comply with the requirements of paragraph (c)(6)(ii) and (c)(7) 10.3.6.2 and 10.3.7 of this regulation beginning as soon as practical, but no later than the date one year after the effective date of this Section 10.0 of this regulation. New, modified, or reconstructed sources affected by this Section 10.0 of this regulation shall comply with the provisions of this Section 10.0 of this regulation on and after startup. Not withstanding Section (1)(e) of Regulation 24 1.5 of this regulation, any owner or operator currently permitted under Regulation 2 and/or Regulation 30 7 DE Admin. Code 1102 or 1130, or both 1102 and 1130 to operate an aerospace manufacturing or rework facility shall submit to the Department an application to amend the current permit and to comply with the provisions of this Section, pursuant to Regulation 2 and/or Regulation 30 7 DE Admin. Code 1102 or 1130, or both 1102 and 1130, as applicable.

10.1.5 5. Any facility that becomes or is currently subject to the provisions of this Section 10.0 of this regulation by exceeding the applicability threshold in paragraph (a)(3) 10.1.3 of this Section regulation shall remain subject to these provisions even if its emissions later fall below the applicability threshold.

10.1.6 6. Any facility that is currently subject to a state or federal rule promulgated pursuant to the Clean Air Act Amendments of 1977 by exceeding an applicability threshold is and shall remain subject to these provisions, even if its throughput or emissions later fall below the applicability threshold.

10.2 b. Definitions. As used in this Section 10.0 of this regulation, all terms not defined herein shall have the meaning given them in the November 15, 1990 Clean Air Act Amendments (CAAA), or in Section 2 of Regulation 24 2.0 of this regulation of the State of Delaware “Regulations Governing the Control of Air Pollution.”

“Ablative coating” means a specialty coating that chars when exposed to open flame or extreme temperatures, as would occur during the failure of an engine casing or during aerodynamic heating. The ablative char surface serves as an insulation barrier, protecting adjacent components from the heat or open flame.

“Adhesion promoter” means a very thin specialty coating applied to a substrate to promote wetting and form a chemical bond with the subsequently applied material.

“Adhesive bonding” means the joining together of two or more metal parts, such as the parts of a honeycomb core. The surfaces to be bonded are first coated with an adhesive bonding primer to promote adhesion and protect from subsequent corrosion. Structural adhesives are applied as either a thin film or as a paste, and can be oven cured or cured in an autoclave.

“Adhesive bonding primer” means a specialty coating that is applied in a thin film to aerospace components for the purpose of corrosion inhibition and increased adhesive bond strength by attachment. There are two categories of adhesive bonding primers: primers with a design cure at 250^oF or below and primers with a design cure above 250^oF.

“Aerospace manufacturing or rework facility” means a commercial, civil, or military facility that produces in any amount an aerospace vehicle or component, or a commercial, civil, or military facility that reworks (or repairs) any aerospace vehicle or component.

“Aerospace vehicle or component” means any fabricated part, processed part, assembly of parts, or completed unit of any aircraft including, but not limited to, airplanes, helicopters, missiles, rockets, and space vehicles.

“Aircraft fluid system” means those systems that handle hydraulic fluids, fuel, cooling fluids, or oils.

“Aircraft transparency” means the aircraft windshield, canopy, passenger windows, lenses and other components that are constructed of transparent materials.

“Antichafe coating” means a coating applied to areas of moving aerospace components that may rub during normal operations or installation.

“Bearing coating” means a specialty coating applied to an antifriction bearing, a bearing housing, or the area adjacent to such a bearing in order to facilitate bearing function or to protect base material from excessive wear. A material shall not be classified as a bearing coating if it can also be classified as a dry lubricative material or a solid film lubricant.

“Bonding maskant” means a temporary specialty coating used to protect selected areas of aerospace parts from strong acid or alkaline solutions during processing for bonding.

“Brush coating” means the application of a coating material to a substrate by means of a brush (this technique is commonly used for touch-up and maskant operations).

“Caulking and smoothing compounds” means semi-solid specialty coating materials which are applied by hand application methods and are used to aerodynamically smooth exterior vehicle surfaces or fill cavities such as bolt hole accesses. A material shall not be classified as a caulking and smoothing compound if it can also be classified as a sealant.

“Chemical agent-resistant coating (CARC)” means an exterior topcoat; specialty coating designed to withstand exposure to chemical warfare agents or the decontaminants used on these agents.

“Chemical milling” means a process used to reduce the thickness of selected areas of metal parts in order to reduce weight by submerging the metal parts in an etchant.

“Chemical milling maskant” means a coating that is applied directly to aluminum components to protect surface areas when chemically milling the component with a Type I or II etchant. Type I chemical milling maskants are used with a Type I etchant and Type II chemical milling maskants are used with a Type II etchant. This definition does not include bonding maskants, critical use and line sealer maskants, and seal coat maskants. Additionally, maskants that must be used with a combination of Type I or II etchants and any of the above types of maskants (i.e., bonding, critical use and line sealer, and seal coat) are not included.

“Chemical milling maskant application” means the use of spray equipment or a dip tank to apply a Chemical milling maskant, prior to chemically milling the component with a Type I or II etchant.

“Cleaning operation” means collectively spray gun, hand-wipe, and flush cleaning operations.

“Cleaning solvent” means a liquid VOC containing material used for hand-wipe, spray gun, or flush cleaning.

“Clear coating” means a transparent coating applied to any substrate.

“Coating” means a material that is applied to the surface of an aerospace vehicle or component to form a decorative, protective, or functional solid film, or the solid film itself.

“Coating operation” means the use of a spray booth, tank, or other enclosure or area, such as a hangar, for the application of a single type of coating (e.g., primer). The use of the same spray booth for the application of another type of coating (e.g., topcoat) constitutes a separate coating operation for which compliance determinations are performed separately.

“Commercial exterior aerodynamic structure primer” means a specialty coating primer used on aerodynamic components and structures that protrude from the fuselage, such as wings and attached components, control surfaces, horizontal stabilizers, vertical fins, wing-to-body fairings, antennae, and landing gear and doors, for the purpose of extended corrosion protection and enhanced adhesion.

“Commercial interior adhesive” means specialty coating materials used in the bonding of passenger cabin interior components that meet the FAA fireworthiness requirements.

“Compatible substrate primer” means a specialty coating that is either a compatible epoxy primer or an adhesive primer. Compatible epoxy primer is primer that is compatible with the filled elastomeric coating and is epoxy based. The compatible substrate primer is an epoxy-polyamide primer used to promote adhesion of elastomeric coatings such as impact-resistant coatings. Adhesive primer is a coating that (1) inhibits corrosion and serves as a primer applied to bare metal surfaces or prior to adhesive application, or (2) is applied to surfaces that can be expected to contain fuel. Fuel tank coatings are excluded from this category.

“Composite processing operations” include layup, thermal forming, debulking, curing, break-out, compression molding, and injection molding. Layup means the process of assembling the layers of the composite structure by positioning composite material in a mold and impregnating the material with a resin. Thermal forming means the process of forming the layup in a mold, which usually takes place in an autoclave. Debulking means the simultaneous application of low-level heat and pressure to the composite structure to force out excess resin, trapped air, vapor, and volatiles from between the layers of the composite structure. Curing means the process of changing the resin into a solid material through a polymerization reaction. Break-out means the removal of the composite structure from the mold or curing fixtures. Compression molding means the process of filling one half of molds with a molding compound, closing the mold, and applying heat and pressure until the material is cured. Injection molding means the use of a closed mold, where the molding compound is injected into the mold, maintained under pressure, and then cured by applying heat.

“Corrosion prevention system” means a coating system that provides corrosion protection by displacing water and penetrating mating surfaces, forming a protective barrier between the metal surface and moisture. Coatings containing oils or waxes are excluded from this category.

“Critical use line and sealer maskant” means a temporary specialty coating, not covered under other maskant categories, used to protect selected areas of aerospace parts from strong acid or alkaline solutions such as those used in anodizing, plating, chemical milling and processing of magnesium, titanium, or high-strength steel, high-precision aluminum chemical milling of deep cuts, and aluminum chemical milling of complex shapes. Materials used for repairs or to bridge gaps left by scribing operations (i.e., line sealer) are also included in this category.

“Cryogenic flexible primer” means a specialty coating primer designed to provide corrosion resistance, flexibility, and adhesion of subsequent coating systems when exposed to loads up to and surpassing the yield point of the substrate at cryogenic temperatures (-275^oF and below).

“Cryoprotective coating” means a specialty coating that insulates cryogenic or subcooled surfaces to limit propellant boil-off, maintain structural integrity of metallic structures during ascent or re-entry, and prevent ice formation.

“Cyanoacrylate adhesive” means a fast-setting, single component specialty coating adhesive that cures at room temperature. Also known as “super glue.”

“Depainting” means the removal of any coating from the outer surface of an aerospace vehicle or component by either chemical or non-chemical means.

“Depainting operation” means the use of a chemical agent, media blasting, or any other technique to remove coatings from the outer surface of aerospace vehicles or components. The depainting operation includes washing of the aerospace vehicle or component to remove residual stripper and coating residue.

“Dip coating” means the application of a coating material to a substrate by dipping the part into a tank of the coating material.

“Dry lubricative material” means a specialty coating consisting of lauric acid, cetyl alcohol, waxes, or other noncross linked or resin-bound materials that act as a dry lubricant.

“Electric or radiation-effect coating” means a specialty coating or coating system engineered to interact, through absorption or reflection, with specific regions of the electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar avoidance. Coatings that have been designated as “classified” by the Department of Defense are exempt.

“Electrodeposition” means an additive process for metal substrates in which another metal layer is added to the substrate in order to enhance corrosion and wear resistance necessary for the successful performance of the component. The two types of electrodeposition typically used are electroplating and plasma arc spraying.

“Electrostatic discharge and electromagnetic interference (EMI) coating” means a specialty coating applied to space vehicles, missiles, aircraft radomes, and helicopter blades to disperse static energy or reduce electromagnetic interference.

“Electrostatic spray” means a method of applying a spray coating in which opposite electrical charges are applied to the substrate and the coating. The coating is attracted to the substrate by the electrostatic potential between them.

“Elevated-temperature Skydrol-resistant commercial primer” means a specialty coating primer applied primarily to commercial aircraft (or commercial aircraft adapted for military use) that must withstand immersion in phosphate-ester (PE) hydraulic fluid (Skydrol 500b or equivalent) at the elevated temperature of 150^oF for 1,000 hours.

“Epoxy polyamide topcoat” means a specialty coating used where harder films are required or where engraving is accomplished in camouflage colors.

“Etchant” means a chemical used to mill a part or subassembly (e.g., sodium hydroxide for aluminum parts).

“Exempt solvent” means an organic compound that has been determined to have negligible photochemical reactivity, as specified, and is defined in Regulation 24, Section 2 2.0 of this regulation under “exempt compounds.”

“Fire-resistant (interior) coating” means for civilian aircraft, fire-resistant interior coatings used on passenger cabin interior parts that are subject to the FAA fire worthiness requirements. For military aircraft, fire-resistant interior coatings mean coatings that are used on parts that are subject to the flammability requirements of MIL-STD-1630A and MIL-A-87721. For space applications, fireresistant interior coatings means coatings that are used on parts that are subject to the flammability requirements of SE-R-0006 and SSP 30233.

“Flexible primer” means a specialty coating primer that meets flexibility requirements such as those needed for adhesive bond primed fastener heads or on surfaces expected to contain fuel. The flexible coating is required because it provides a compatible, flexible substrate over bonded sheet rubber and rubber-type coatings as well as a flexible bridge between the fasteners, skin, and skin-to-skin joints on outer aircraft skins. This flexible bridge allows more topcoat flexibility around fasteners and decreases the chance of the topcoat cracking around the fasteners. The result is better corrosion resistance.

“Flow coating” means the application of a coating material to a substrate by pouring the coating over the suspended part.

“Flush cleaning” means the cleaning of an aerospace vehicle or component by passing solvent over, into, or through the vehicle or component. The solvent may simply be poured into the vehicle or component and then drained, or assisted by air or hydraulic pressure, or by pumping. Hand-wipe cleaning operations where wiping, scrubbing, mopping, or other hand action is used are not flush cleaning operations.

“Formulation” means a specific coating made by a specific manufacturer. Each different color of a specific coating is considered a separate formulation.

“Fuel tank adhesive” means a specialty coating adhesive used to bond components exposed to fuel which shall be compatible with fuel tank coatings.

“Fuel tank coating” means a specialty coating applied to fuel tank components for the purpose of corrosion and/or bacterial growth inhibition, and to assure sealant adhesion in extreme environmental conditions.

“Hand-wipe cleaning operation” means the removal of contaminants such as dirt, grease, oil, and coatings from aerospace vehicles or components by physically rubbing them with a material such as a rag, paper, or cotton swab that has been moistened with a cleaning solvent.

“High temperature coating” means a specialty coating designed to withstand temperatures of more than 350^oF.

“High volume low pressure (HVLP) spray equipment” means spray equipment that is used to apply coatings using a spray gun that operates at equal to or less than 10.0 psig of atomized air pressure at the air cap.

“Insulation covering” means a specialty coating material that is applied to foam insulation to protect the insulation from mechanical or environmental damage.

“Intermediate release coating” means a thin specialty coating applied beneath topcoats to assist in removing the topcoat in depainting operations, which generally allows the use of less hazardous depainting methods.

“Lacquer” means a clear or pigmented specialty coating formulated with a nitrocellulose or synthetic resin to dry by evaporation without a chemical reaction. Lacquers are resoluble in their original solvent.

“Leak” means any visible leakage, including misting and clouding.

“Limited access space” means internal surfaces or passages of an aerospace vehicle or component that cannot be reached for the application of coatings without the aid of an airbrush or a spray gun extension.

“Metal finishing” means conversion coating, anodizing, desmutting, descaling, and any operation that chemically affect the surface layer of a part, and is used to prepare the surface of a part for better adhesion, improved surface hardness, and improved corrosion resistance.

“Metalized epoxy coating” means a specialty coating that contains relatively large quantities of metallic pigmentation for appearance and/or added protection.

“Mold release” means a specialty coating applied to a mold surface to prevent the molded piece from sticking to the mold as it is removed.

“Non-chemical-based depainting equipment” means any depainting equipment or technique that does not rely on a chemical stripper to depaint an aerospace vehicle or component (e.g., media blasting equipment).

“Nonstructural adhesive” means a specialty coating adhesive that bonds nonload bearing aerospace components in noncritical applications and is not covered in any other specialty adhesive categories.

“Optical anti-reflective coating” means a coating with a low reflectance in the infrared and invisible wavelength ranges that is used for anti-reflection on or near optical and laser hardware.

“Part marking coating” means a specialty coating or ink used to make identifying markings on materials, components, and/or assemblies. These markings may be either permanent or temporary.