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Subchapter 1. Unfired Pressure Vessel Safety Orders
Article 3. Air Tanks
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§466. Repairs and Alterations.

(a) No alteration or repair affecting the safety of any air tank covered by these Orders shall be made without the authorization of a qualified inspector.

(b) Any air tank which has suffered mechanical damage causing dents or other deformations exceeding a depth of 1 1/2 times the thickness of the deformed head or shell or two percent of the tank diameter, whichever is greater, shall be properly reformed to its original shape or otherwise repaired as provided in these Orders. Deformations less than these amounts located in areas of high stress concentration and/ or having abrupt changes in configuration may be required to be reformed to their original shape at the discretion of the qualified inspector.

(c) Any areas that are deteriorated by internal or external corrosion or by mechanical abrasion that affects the safety of the tank shall be properly re-aired or the allowable working pressure shall be reduced proportionately. The building up by welding of such area is prohibited, except isolated pits shall be permitted to be properly prepared and welded at the discretion of the qualified inspector.

(d) No welded repair shall be permitted on a tank of brazed construction. If inspection openings are required in such tanks, they may be machine-cut and closed with handhole plates.

(e) Any welding necessary when making major repairs or alterations to tanks shall be done by a welder qualified in accordance with Section IX of the ASME Code in the position or positions used in making the repair or alteration.

(1) When minor welding repairs or alterations, such as closing openings not exceeding 2 inch pipe size, installing reinforcing rings around handhole openings, installing staybolts or through stays, etc., are made by a welder who is not ASME qualified, these repairs or alterations shall be authorized and approved by a qualified inspector.

(f) The qualified inspector who authorizes any welded repair or alteration shall report it to the Division within 21 days, giving full details, including the State serial number of the tank, the name and address of the owner or user, the location of the tank, and the name and address of the welder and the welder's employer.

(1) The qualified inspector shall stamp his/her certificate of competency number adjacent to all welded repairs authorized.

(g) If the longitudinal seam of any non-code air tank of welded construction is found to have incomplete penetration of the welded joint, the tank shall not be repaired. Such tanks shall be permanently removed from service, with the rejection mark affixed by the qualified inspector, as required in Section 462(i).

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


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

2. Amendment filed 1-5-88; operative 2-4-88 (Register 88, No. 4).

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