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Subchapter 2. Boiler and Fired Pressure Vessel Safety Orders
Article 4. Installation
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§761. Safety Valves and Pressure Relieving Devices, Boilers.

(a) Each power boiler, nuclear boiler, and high temperature water boiler shall have safety valves or pressure relieving devices constructed, stamped and installed in accordance with the applicable section of the Code, except:

(1) For existing installations the stamping required by the Code at the time of original installation may be accepted until the valves are replaced.

(2) Upon written request by the employer, the Division may permit three-way two-port valves to be installed under two safety valves, each with the required relieving capacity, provided they are so installed that both safety valves cannot be closed off from the boiler at the same time and provided the three-way valve will permit at least full flow to the safety valve in service at all time.

(b) The user shall maintain all pressure relieving devices in good operating condition. Where the valves cannot be tested in service, the user shall maintain and make available to the inspector records showing the test dates and set pressure for such valves.

(c) Pressure relieving devices with open discharge installations shall have piping and supports designed for pressure relief reaction forces in accordance with Appendix II of ANSI B 31.1.

The discharge from pressure relieving devices shall be piped to a safe location where:

(1) The discharge of steam or hot water will not present a hazard to employees.

(2) The discharge of steam or water will not be detrimental to any electrical or other machinery or equipment.

(3) The discharge pipe cannot be readily plugged or otherwise obstructed.

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


1. Amendment filed 11-2-66; effective thirtieth day thereafter (Register 66, No. 38). Approved by State Building Standards Commission.

2. Amendment filed 6-16-79; effective thirtieth day thereafter (Register 79, No. 24).

3. Change without regulatory effect inserting "(a)" immediately preceding the first paragraph and "(b)" immediately preceding the fourth paragraph, filed 1-24-91 pursuant to section 100, Title 1, California Code of Regulations (Register 91, No. 7).

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