Rule 637.
Excess Non-Monomer VOC = Non-monomer VOC Content - 5%, by weight
TABLE 69-a
Alternative volatile organic compound content requirements for molding resin and gel coat operations.
Operation | Application Method | Weighted-Average Monomer VOC Content (weight percent) |
Production resin | Atomized | 28.0 |
Production resin | Nonatomized | 35.0 |
Pigment gel coat | Any method | 33.0 |
Clear gel coat | Any method | 48.0 |
Tooling resin | Atomized | 30.0 |
Tooling resin | Nonatomized | 39.0 |
Tooling gel coat | Any method | 40.0 |
Equation 6-1:
Monomer VOC Limit = 46(MR)+159(MPG)+291(MCG)+54(MTR)+214(MTG)
Where:
Monomer = Total allowable monomer volatile organic compound that can VOC be emitted from the open molding operations included in the limit average, expressed in kilograms per 12-month period.
MR = Mass of production resin used in the past 12 months, excluding any materials that are exempt, expressed in megagrams (Mg).
MPG = Mass of pigmented gel coat used in the past 12 months, excluding any materials that are exempt, expressed in Mg.
MCG = Mass of clear gel coat used in the past 12 months, excluding any materials that are exempt, expressed in Mg.
MTR = Mass of tooling resin used in the past 12 months, excluding any materials that are exempt, expressed in Mg.
MTG = Mass of tooling gel coat used in the past 12 months, excluding any materials that are exempt, expressed in Mg.
The numerical coefficients associated with each term on the righthand side of equation 6-1 are the allowable monomer volatile organic compound emission rates for that particular material in units of kg VOC/Mg of material used.
EQUATION 6-2:
Monomer VOC Emissions = (PVR)(MR) + (PVPG)(MPG) + (PVCG)(MCG) + (PVTR)(MTR) + (PVTG)(MTG)
Where:
Monomer VOC Emissions= Monomer volatile organic compound emissions calculated using the monomer volatile organic compound emission equations for each operation included in the average, expressed in kilograms.
PVR = Weighted-average monomer volatile organic compound emission rate for production resin used in the past 12 months, expressed in kg/Mg, calculated in accordance with equation 6-3 in subdivision (c)(iii) of this subrule.
MR = Mass of production resin used in the past 12 months, expressed in Mg.
PVPG = Weighted-average monomer volatile organic compound emission rate for pigmented gel coat used in the past 12 months, expressed in kg/Mg, calculated pursuant to equation 6-3.
MPG = Mass of pigmented gel coat used in the past 12 months, expressed in Mg.
PVCG = Weighted-average monomer volatile organic compound emission rate for clear gel coat used in the past 12 months, expressed in kg/Mg, calculated pursuant to equation 6-3.
Mcg = Mass of clear gel coat used in the past 12 months, expressed in Mg.
PVTR = Weighted-average monomer volatile organic compound emission rate for tooling resin used in the past 12 months, expressed in kg/Mg, calculated pursuant to equation 6-3.
MTR = Mass of tooling resin used in the past 12 months, expressed in Mg.
PVTG = Weighted-average monomer volatile organic compound emission rate for tooling gel coat used in the past 12 months, expressed in kg/Mg, calculated pursuant to equation 6-3.
MTG = Mass of tooling gel coat used in the past 12 months, expressed in Mg.
EQUATION 6-3:
Where:
PVop = Weighted-average monomer volatile organic compound emission rate for each open molding operation (PVR, PVPG, PVCG, PVTR, and PVTG) included in the average, expressed in kg of monomer volatile organic compound per Mg of material applied.
Mi = Mass of resin or gel coat (i) used within an operation in the past 12 months, expressed in Mg.
n = Number of different open molding resins and gel coats used within an operation in the past 12 months.
PVi = The monomer volatile organic compound emission rate for resin or gel coat (i) used within an operation in the past 12 months, expressed in kg of monomer volatile organic compound per Mg of material applied. The monomer volatile organic compound emission rate formulas in paragraph (iv) of this subdivision must be used to compute PVi. If a source includes filled resins in the emissions average, the source must use the value of PVF, calculated using equation 6-4 in subdivision (f)(iii) of this subrule as the value of Pvi for those resins.
i = Subscript denoting a specific open molding resin or gel coat applied.
TABLE 69-b
Monomer volatile organic compound emission rate formulas for molding operations.
Operation | Application Method | Formula to calculate the monomer VOC emission rate. |
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 | Nonatomized | 0.014 x (Resin VOC%)2.275 |
Production resin, tooling resin | Nonatomized, plus vacuum bagging with roll-out | 0.0110 x (Resin VOC%)2.275 |
Production resin, tooling resin | Nonatomized, plus vacuum bagging without roll-out | 0.0076 x (Resin VOC%)2.275 |
Pigmented gel coat, clear gel coat, tooling gel coat | All methods | 0.445 x (Gel coat VOC%)1.675 |
PVF = (PVU)(100 - percent filler) / 100
Where:
PVF = The as-applied monomer volatile organic compound emission rate for a filled production resin or tooling resin, pounds of monomer volatile organic compound per ton of filled material.
PVU = The monomer volatile organic compound emission rate for the neat (unfilled) resin, before filler is added, as calculated using the formulas in table 69-b of this rule.
Percent filler = The weight-percent of filler in the as-applied filled resin system.
Mich. Admin. Code R. 336.1637