25 Pa. Code § 129.74
(a) Applicability.
(2) This section does not apply to the owner and operator of a facility that manufactures boat trailers or parts of boats, such as hatches, seats and lockers, but does not manufacture hulls or decks of boats from fiberglass or build molds to make fiberglass boat hulls or decks.
| Open Molding Resin or Gel Coat Material | Application Method | Individual Monomer VOC Content or Weighted Average Monomer VOC Content (weight percent) |
| Production Resin | Atomized Spray | 28 |
| Production Resin | Non-atomized | 35 |
| Pigmented Gel Coat | Any Method | 33 |
| Clear Gel Coat | Any Method | 48 |
| Tooling Resin | Atomized Spray | 30 |
| Tooling Resin | Non-atomized | 39 |
| Tooling Gel Coat | Any Method | 40 |
(b) Definitions. The following words and terms, when used in this section, have the following meanings, unless the context clearly indicates otherwise:
(ii) The term includes resin spray guns and resin chopper spray guns.
Boat—A vessel, other than a seaplane, that can be used for transportation on the water.
Clear gel coat—
(ii) The term does not include tooling gel coats used to build or repair molds.
Closed molding—
(iii) The term does not include:
(B) Open molding steps, such as application of a gel coat or skin coat layer by conventional open molding.
Cured resin—A thermosetting plastic material containing styrene or methyl methacrylate or gel coat that has changed irreversibly from a liquid to a solid.
Fiberglass—A material consisting of glass fibers made in the form of cloth, mat or roving.
Fiberglass boat—A vessel in which either the hull or deck, or both, is built from a composite material consisting of a thermosetting resin matrix reinforced with fibers of glass, carbon, aramid or other material.
Filled resin—A thermosetting plastic material to which an inert material has been added to change viscosity, density, shrinkage or other physical properties, particularly for building molds.
Flowcoater—A non-atomizing application method of applying resins and gel coats to an open mold with a fluid nozzle in a fan pattern with no air supplied to the nozzle.
Gel coat—
(ii) The term includes a clear or pigmented polyester resin mixed with metal flakes.
Glass cloth—A fabric made of woven yarns of glass fibers.
Glass mat—A prepared material consisting of short glass fibers that are fixed to each other in a random pattern by a chemical binder or are mechanically stitched to a lightweight fabric.
Glass roving—A bundle of continuous glass fibers that is fed from a spool to a specialized gun that chops the bundle into short fibers, mixes the fibers with catalyzed resin and deposits the mixture on the mold surface in a random pattern.
Mixing—An operation in which resin or gel coat, including the mixing of putties or polyester resin putties, is combined with additives that include fillers, promoters or catalysts.
Mold—
(ii) The term is also known as a tool.
Monomer VOC—A VOC that partially combines with itself or other similar compounds by a cross-linking reaction to become a part of the cured resin.
Monomer VOC content—The weight of the monomer divided by the weight of the polymer.
Non-atomized application method—
(ii) The term includes flowcoaters, chopper flowcoaters, pressure-fed resin rollers, resin impregnators and hand application (for example, paint brush or paint roller).
Open molding—
(ii) The term includes:
(C) A process in which a closed mold is used only to compact saturated fabric or to remove air or excess resin from the fabric (such as in vacuum bagging).
Pigmented gel coat—
(ii) The term does not include tooling gel coats used to build or repair molds.
Plug—
(ii) The term is also known as a prototype.
Polyester resin material—An unsaturated thermosetting plastic material, such as an isophthalic, orthophthalic, halogenated, bisphenol A, vinylester or furan resin, a cross-linking agent, a catalyst, a gel coat, an inhibitor, an accelerator, a promoter or other material containing VOC used in polyester resin operations.
Polyester resin operation—A process in which an unsaturated polyester resin material is used to fabricate, rework, repair or touch-up a product for commercial, military or industrial use by mixing, pouring, hand laying-up, impregnating, injecting, forming, winding, spraying or curing.
Polyputty or putty—A polyester or vinylester resin mixed with inert fillers or fibers. The mixture is used to assemble fiberglass parts and to fill gaps between parts. The applied material becomes part of the composite structure. These materials are not considered industrial adhesives.
Production resin—
(ii) The term does not include tooling resins used to build or repair molds and assembly adhesives.
Repair—The addition of polyester resin material to a portion of a previously fabricated product to mend damage.
Resin—A thermosetting plastic material containing styrene or methyl methacrylate, with or without pigment, used to encapsulate and bind together reinforcement fibers in the construction of fiberglass parts.
Resin impregnator—A mechanical non-atomizing composite material application method in which fiber reinforcement is saturated with one or more resins in a controlled ratio for each specific composite product.
Roll-out—The process of using rollers, squeegees or similar tools to compact reinforcing materials saturated with resin to remove trapped air or excess resin.
Skin coat—A layer of resin and fibers applied over the gel coat to protect the gel coat from being deformed by the next laminate layer.
Tooling gel coat—A polyester resin material containing styrene or methyl methacrylate, or both, that becomes the interior surface of a mold, supported by resin and fiberglass, or the exterior surface of a plug used to create a mold or is used to repair a mold.
Tooling resin—A thermosetting plastic material, hardened by a catalyst, used to construct or repair a mold or a plug for a mold for the manufacture of a fiberglass boat hull, deck or other part.
Touch-up—The application of material to cover minor imperfections.
Vacuum bagging—
(ii) The term does not include a process that meets the definition of ‘‘closed molding.’’
Vacuum bagging with roll-out—A partially closed molding technology that rolls the resin and fabric before the application of vacuum bagging materials.
Vacuum bagging without roll-out—A partially closed molding technology that applies vacuum bagging materials to the mold immediately after resin application without rolling the resin and fabric.
Vinylester resin—A thermosetting plastic material containing one or more esters of acrylic or methacrylic acids and having double-bond and ester linkage sites only at the ends of the resin molecules.
Application equipment cleaning—The process of flushing or removing resin or gel coat material, or both, from the interior or exterior of equipment that is used to apply resins or gel coats in the manufacture of fiberglass parts.
Assembly adhesives—A chemical substance that is applied for the purpose of bonding two surfaces together other than by mechanical means.
Atomized application method—
(c) Exceptions. The requirements of this section do not apply to the following circumstances:
(f) Emission limits. Except as specified in subsection (h) or (j), the owner and operator of a facility subject to this section may not cause or permit the emission into the outdoor atmosphere of monomer VOCs from an open molding resin or gel coat fiberglass boat manufacturing operation, a resin or gel coat mixing operation, or a resin or gel coat application equipment cleaning operation unless one or more of the following limitations is met:
(1) Compliant materials option. The individual monomer VOC content limit is achieved through the use of low-monomer VOC content open molding resin and gel coat materials by one or more of the following methods:
(i) Using only low-monomer VOC content resin and gel coat materials within a covered operation listed in Table I.
(ii) Averaging the monomer VOC contents for the open molding resin and gel coat materials used within a covered operation listed in Table I on a weight-adjusted basis.
(C) The weighted-average monomer VOC content on a 12-month rolling-average basis shall be calculated as follows:
Where:
Mi = Mass of open molding resin or gel coat i used in the past 12 months in an operation, in megagrams.
VOCi = Monomer VOC content, by weight percent, of open molding resin or gel coat i used in the past 12 months in an operation.
n = Number of different open molding resins or gel coats used in the past 12 months in an operation.
(2) Emissions averaging option. The numerical monomer VOC emission rate limit is achieved through averaging emissions among different open molding resin and gel coat operations. The equations in subparagraphs (iii)—(v) shall be used to estimate the monomer VOC emission rates from each operation included in the emissions averaging option based on the material and application method.
(iii) The facility-specific monomer VOC mass emission limit on a 12-month rolling-average basis shall be calculated as follows:
Where:
Monomer VOC Limit = Total allowable monomer VOC that can be emitted from the open molding operations included in the emissions averaging program, in kilograms per 12-month period.
MR = Mass of production resin used in the past 12 months, excluding exempt VOC materials, in megagrams.
MPG = Mass of pigmented gel coat used in the past 12 months, excluding exempt VOC materials, in megagrams.
MCG = Mass of clear gel coat used in the past 12 months, excluding exempt VOC materials, in megagrams.
MTR = Mass of tooling resin used in the past 12 months, excluding exempt VOC materials, in megagrams.
MTG = Mass of tooling gel coat used in the past 12 months, excluding exempt VOC materials, in megagrams.
Numerical coefficients = The allowable monomer VOC emission rate for that particular material, in units of kg/Mg of material used.
(iv) At the end of the first 12-month rolling-average emissions period and at the end of each subsequent calendar month, the owner or operator of the facility shall demonstrate that the monomer VOC emissions from the operations and materials included in the emissions averaging option do not exceed the emission limit calculated under subparagraph (iii) for the same 12-month period as follows:
Where:
Monomer VOC emissions = Monomer VOC emissions calculated using the monomer VOC emission equation for each operation included in the emissions averaging program, in kilograms.
PVR = Weighted-average monomer VOC emission rate for production resin used in the past 12 months, in kilograms per megagram.
MR = Mass of production resin used in the past 12 months, in megagrams.
PVPG = Weighted-average monomer VOC emission rate for pigmented gel coat used in the past 12 months, in kilograms per megagram.
MPG = Mass of pigmented gel coat used in the past 12 months, in megagrams.
PVCG = Weighted-average monomer VOC emission rate for clear gel coat used in the past 12 months, in kilograms per megagram.
MCG = Mass of clear gel coat used in the past 12 months, in megagrams.
PVTR = Weighted-average monomer VOC emission rate for tooling resin used in the past 12 months, in kilograms per megagram.
MTR = Mass of tooling resin used in the past 12 months, in megagrams.
PVTG = Weighted-average monomer VOC emission rate for tooling gel coat used in the past 12 months, in kilograms per megagram.
MTG = Mass of tooling gel coat used in the past 12 months, in megagrams.
(v) For purposes of subparagraph (iv), the owner or operator of the facility shall determine the weighted-average monomer VOC emission rate for the previous 12 months for each open molding resin and gel coat operation included in the emissions averaging option as follows:
Where:
PVOP = Weighted-average monomer VOC emission rate for each open molding operation (PVR, PVPG, PVCG, PVTR, PVTG) included in the emissions averaging program, in kilograms of monomer VOC per megagram of material applied.
Mi = Mass of resin or gel coat used within an operation in the past 12 months, in megagrams.
n = Number of different open molding resins and gel coats used within an operation within the past 12 months.
PVi = The monomer VOC emission rate for resin or gel coat used within an operation in the past 12 months, in kilograms of monomer VOC per megagram of material applied. PVi shall be calculated using the applicable emission rate formula specified in Table II.
| Open Molding Resin or Gel Coat Material | Application Method | Emission Rate Formula |
| Production Resin, Tooling Resin | Atomized | 0.014 x (Resin VOC%)2.425 |
| Production Resin, Tooling Resin | Atomized, plus vacuum bagging with roll-out | 0.01185 x (Resin VOC%)2.425 |
| Production Resin, Tooling Resin | Atomized, plus vacuum bagging without roll-out | 0.00945 x (Resin VOC%)2.425 |
| Production Resin, Tooling Resin | Non-atomized | 0.014 x (Resin VOC%)2.275 |
| Production Resin, Tooling Resin | Non-atomized, plus vacuum bagging with roll-out | 0.0110 x (Resin VOC%)2.275 |
| Production Resin, Tooling Resin | Non-atomized, plus vacuum bagging without roll-out | 0.0076 x (Resin VOC%)2.275 |
| Pigmented Gel Coat | All methods | 0.445 x (Resin VOC%)1.675 |
| Clear Gel Coat | All methods | 0.445 x (Resin VOC%)1.675 |
| Tooling Gel Coat | All methods | 0.445 x (Resin VOC%)1.675 |
(3) VOC emissions capture system and add-on air pollution control device option. A numerical monomer VOC emission rate, determined for a facility based on the mix of application methods and materials used at the facility, is achieved through the use of a VOC emissions capture system and add-on air pollution control device.
(g) VOC emissions capture system and add-on air pollution control device requirements. The owner or operator of a facility subject to this section may elect to comply with the applicable emission limitations of this section through the installation of a VOC emissions capture system and add-on air pollution control device in accordance with subsection (f)(3). The owner or operator shall submit an application for a plan approval to the appropriate regional office. The application for a plan approval must be approved, in writing, by the Department prior to installation and operation of the emissions capture system and add-on air pollution control device. The application for a plan approval must include the following information:
(h) Emission limits for filled production resins and filled tooling resins. The owner or operator may use an open molding filled production resin or filled tooling resin in each of the emission limit options specified in subsection (f).
(1) If fillers are added to the resin material, the adjusted monomer VOC emission rate of the filled material must be calculated on an as applied basis as follows:
PVF = PVU x (100 - % Filler)
100
Where:
PVF = The as-applied monomer VOC emission rate for the filled production resin or tooling resin, in kilograms per megagram of filled material.
PVU = The monomer VOC emission rate for the neat (unfilled) resin, before filler is added, calculated using the applicable emission rate formula in Table II.
% Filler = The weight-percent of filler in the as applied resin system.
(4) The monomer VOC content of each as applied filled resin includes the amount of non-monomer VOC content that exceeds 5% by weight of the unfilled resin material.
(j) Alternative requirements for control of monomer VOC content for certain resin and gel coat materials. The monomer VOC content limits in Table I do not apply to a tooling or production material used for the following purposes:
(l) VOC content limits and work practices for cleaning materials. The owner or operator of a facility subject to this section shall comply with the following VOC content limits and work practices for VOC-containing cleaning materials:
(m) Compliance and monitoring requirements. The owner or operator of a facility subject to this section shall:
(n) Sampling and testing. The owner or operator of a facility subject to this section shall perform sampling and testing as follows:
(1) Use one or more of the following methods to determine the monomer VOC content of a resin or gel coat.
(o) Recordkeeping requirements. The owner or operator of a facility subject to this section shall maintain monthly records sufficient to demonstrate compliance with this section. The records must include the following information:
The provisions of this § 129.74 issued under section 5(a)(1) and (8) of the Air Pollution Control Act (35 P.S. § 4005(a)(1) and (8)).
The provisions of this § 129.74 adopted December 18, 2015, effective December 19, 2015, 45 Pa.B. 7127.
This section cited in 25 Pa. Code § 129.96 (relating to applicability); and 25 Pa. Code § 129.111 (relating to applicability).