(1) Conformance. Drying, curing, or fusion apparatus in connection with spray application of flammable and combustible finishes must conform to the Standard for Ovens and Furnaces, NFPA 86A-1969, where applicable and must also conform with the following requirements of this section.

(2) Alternate use prohibited. You must not alternately use spray booths, rooms, or other enclosures used for spraying operations for the purpose of drying by any arrangement which will cause a material increase in the surface temperature of the spray booth, room, or enclosure.

(3) Adjacent system interlocked. Except as specifically provided in (4) of this section, you must not install drying, curing, or fusion units utilizing a heating system having open flames or which may produce sparks in a spraying area, but may be installed adjacent thereto when equipped with an interlocked ventilating system arranged to:

(a) Thoroughly ventilate the drying space before the heating system can be started;

(b) Maintain a safe atmosphere at any source of ignition;

(4) Alternate use permitted. Automobile refinishing spray booths or enclosures, otherwise installed and maintained in full conformity with this section, may alternately be used for drying with portable electrical infrared drying apparatus when conforming with the following:

(a) You must keep interior (especially floors) of spray enclosures free of overspray deposits.

(b) During spray operations, you must not locate the drying apparatus and electrical connections and wiring thereto within spray enclosure nor in any other location where spray residues may be deposited thereon.

(c) You must equip the spraying apparatus, the drying apparatus, and the ventilating system of the spray enclosure with suitable interlocks so arranged that:

(i) The spraying apparatus cannot be operated while the drying apparatus is inside the spray enclosure.

(ii) The spray enclosure will be purged of spray vapors for a period of not less than 3 minutes before the drying apparatus can be energized.

(iii) The ventilating system will maintain a safe atmosphere within the enclosure during the drying process and the drying process apparatus will automatically shut off in the event of failure of the ventilating system.

(d) All electrical wiring and equipment of the drying apparatus must conform with the applicable sections of chapter 296-24 WAC Part L. Only equipment of a type approved for Class I, Division 2 hazardous locations must be located within 18 inches of floor level. All metallic parts of the drying apparatus must be properly electrically bonded and grounded.

(e) The drying apparatus must contain a prominently located, permanently attached warning sign indicating that ventilation should be maintained during the drying period and that spraying should not be conducted in the vicinity that spray will deposit on apparatus.

PDFWAC 296-24-37019

Drying, curing, or fusion apparatus.