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Subchapter 1. Unfired Pressure Vessel Safety Orders
Article 6. Anhydrous Ammonia

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§502. Warning Signs.

(a) Except as noted in Section 502 (b), all anhydrous ammonia tanks 60 gallons capacity or more shall have warning signs provided on at least 2 sides with the words

"Caution -- Ammonia" in sharply contrasting colors, with letters at least 1/12 of the tank diameter in height, but need not be in excess of 1 1/2 inches for tanks 500 gallons capacity or less or 4 inches for tanks exceeding 500 gallons capacity.

(b) All tanks used for the transportation of ammonia on the highways shall be marked as specified by the DOT and adopted by Section 1222, California Administrative Code, under authority to the Division in lieu of the markings required under Section 502 (a) for such tanks in off-highway service.

(c) Uninsulated containers shall have a highly reflective surface maintained in good condition.


1. Amendment filed 12-8-72 as procedural and organizational; effective upon filing (Register 72, No. 50).

2. New subsection (c) filed 3-28-75; effective thirtieth day thereafter (Register 75, No. 13).

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