The ventilation of spray booths and spray areas shall comply with the provisions of Title 14M and with the following:
(a) All spraying areas shall be provided with positive, mechanical ventilation adequate to prevent the dangerous accumulation of vapors and to safely remove such vapors to a safe location.
(b) Such mechanical ventilation shall be kept in operation at all times while the spraying operations are being conducted and for a sufficient time thereafter to allow vapors from drying coated articles and finishing material residues to be exhausted.
(c) Each spray booth shall have an independent exhaust duct system discharging to the building exterior and shall comply with the ventilation requirements of this Code. Multiple-cabinet spray booths in which identical spray-finishing materials is used with a combined frontal area of not more than 18 square feet, may have a common exhaust. If more than one fan serves one booth, all fans shall be so interconnected that one fan cannot operate without operating all.
(d) Electric motors driving exhaust fans shall not be placed inside of booths or ducts. Fan rotating element shall be nonferrous or nonsparking or the casing shall consist of or be lined with such material.
(e) Belts shall not enter the booth or ducts unless such belts and pulleys within the booth or ducts are tightly enclosed.
(f) Exhaust ducts shall be constructed of steel and shall be substantially supported. Readily accessible cleanout openings shall be provided.
(g) Exhaust ducts shall have a clearance from unprotected combustible construction or material of not less than 18 inches. If such combustible construction is provided with the following protection applied to all surfaces within 18 inches, clearances may be reduced to the clearances indicated:
1. 28-gauge sheet metal or one-fourth-inch asbestos mill-board ..... 12 inches
2. 28-gauge sheet metal or one-eighth-inch asbestos mill-board spaced out one inch on noncombustible spacers ..... 9 inches
3. 22-gauge sheet metal or one-inch rockwool batts reinforced with wire mesh or the equivalent ..... 3 inches
4. Air exhaust from spraying operation shall not be recirculated.
(Prior code § 129.1-55; Amend Coun. J. 10-7-20, p. 21791, Art. VI, § 40)