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Subchapter 7. General Industry Safety Orders
Group 20. Flammable Liquids, Gases and Vapors
Article 137. Spray Coating Operations

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§5461. Organic Peroxides and Dual Component Coatings.

(a) Extreme care shall be exercised at all times to prevent the contamination of organic peroxide initiators with any foreign substance. Only spray guns and related handling equipment specifically manufactured for use with organic peroxides shall be used. Separate pressure vessels and inserts specific for the application shall be used for the resin and for the organic peroxide and they shall not be interchanged.

(b) Organic peroxide pressure tank inserts shall be constructed of stainless steel, polyethylene, or other chemically nonreactive materials.

(c) Extreme care shall be exercised to prevent any mixing of dusts or overspray residues resulting from the sanding or spraying of finishing materials containing organic peroxides with other materials. Such mixing may result in a spontaneous fire or explosion.

(d) All spilled peroxides shall be promptly removed so there are no residues. Spilled material may be absorbed by using a noncombustible absorbent and then promptly disposed of in accordance with the manufacturer's recommendation.

(e) Organic peroxides shall be stored in a cool, detached building apart from other finishing materials, and only minimum daily requirements shall be brought to the processing area; such material remaining at the spraying station at the end of a day's operations shall be carefully disposed of. Organic peroxides shall be kept away from all sources of heat including steam pipes, radiators, open flames or sparks and solar radiation.

(f) Extreme care shall be exercised in handling organic peroxides to avoid shock and friction which can cause decomposition and violent reaction.

(g) Organic peroxides shall not be mixed directly with any accelerators or promoters as violent decomposition or explosion may result.

(h) Smoking shall be prohibited and "No Smoking" signs shall be prominently displayed and only nonsparking tools shall be used in any area where organic peroxides are stored, mixed or applied.

(i) Only specifically trained personnel shall be permitted to work with these materials.

(j) Spraying with organic peroxides and other dual-component coatings shall be conducted only in sprinkler-equipped spray booths.

(k) All wetted portions of organic peroxide handling equipment shall be constructed of stainless steel (300 series), polyethylene, Teflon (registered trademark) or other materials which are specifically recommended for the application.

NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.


1. New subsection (j) filed 12-12-84; effective thirtieth day thereafter (Register 84, No. 50).

2. Amendment of subsection (g) and new subsection (k) filed 12-5-86; effective thirtieth day thereafter (Register 86, No. 51).

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