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Subchapter 1. Unfired Pressure Vessel Safety Orders
Article 1. Scope of These Orders
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§450. Application of the Unfired Pressure Vessel Safety Orders.

(a) These Orders apply to places of employment in California, and establish minimum standards for:

(1) The design, construction, and installation of LP-Gas containers, including the storage and handling of LP-Gas. National Fire Protection Association (NFPA) 58, LP-Gas Code, 1998 Edition, is hereby incorporated by reference. Supplementing NFPA 58 are these Safety Orders, beginning with Sections 470 through 494, which are determined necessary for the protection of the safety and health of employees.

(2) The design and construction of all other non-LP-Gas unfired pressure vessels.

(3) The installation, use, repair, and alteration of air tanks, LP-Gas and NH3 tanks and systems.

(4) The inspection of and issuance of permits to operate for air and LP-Gas tanks.

(5) The design, construction, installation, use, repair, and alteration of pressure vessels for the storage and dispensing of natural gas as a motor fuel, except in vehicles that are licensed to travel on highways.

(6) The design, construction, repair and alteration of LNG, LPG and NH3 storage tanks for operation at 15 psig or less.

(b) After the date on which these Orders become effective, all installations and equipment shall conform to these Orders, except as noted in Section 451.

Exception: Existing installations and equipment which were and remain in compliance with the Safety Orders, or variances therefrom, in effect at the time of manufacture or installation.

(c) When any provision of these Safety Orders conflicts with NFPA 58 and is more stringent than the corresponding Section of NFPA 58, the Safety Order shall take precedence.


Authority cited: Section 142.3 Labor Code; and Section 13241, Health and Safety Code. Reference: Section 142.3, Labor Code.


1. Repealer of Subchapter 1 and new Subchapter 1 (T8-450 through T8-467, 470 through T8-485, 488 through 494, T8-500 through T8-513, and T8-550) filed 7-17-70; effective thirtieth day thereafter (Register 70, No. 29). Approved by State Building Standards Commission 6-26-70. For prior history, see Registers 58, No. 38; 64, No. 9; and 68, No. 38.

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

3. Amendment of subsection (a) filed 3-29-74; effective thirtieth day thereafter (Register 74, No. 13).

4. Repealer of subsection (b) and new subsection (b) filed 8-6-76; effective thirtieth day thereafter (Register 76, No. 32).

5. Amendment of subsection (b) filed 7-6-79 as procedural and organizational; effective upon filing (Register 79, No. 27).

6. New subsection (a)(6) filed 1-17-80; effective thirtieth day thereafter (Register 80, No. 3).

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

8. Amendment of section and Note filed 12-4-96; operative 1-3-97 (Register 96, No. 49).

9. Amendment of subsections (a)(1) and (a)(6)-(c) filed 1-30-2002; operative 3-1-2002 (Register 2002, No. 5).

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