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Subchapter 15. Petroleum Safety Orders--Refining, Transportation and Handling
Article 11. Opening and Blinding Pipe Lines and Equipment
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§6816. Blinding or Isolating of Pipe Lines and Equipment for Entry.

(a) Isolation of equipment shall be accomplished by blinding or disconnecting and disaligning. Where equipment, operations or conditions will not allow blinding or disconnecting and disaligning, double blocking with a bleeder (located between the block valves) may be utilized to isolate pipelines or equipment under the following conditions:

(1) Written standard operating procedures must be approved by the location management and be available where the double blocking bleeder system will be used.

(2) Block valves used in double blocking bleeder systems shall be monitored for leakage while employees are in the confined space.

(3) Double block valves shall be tagged and locked in the closed position. The bleeder shall be tagged and locked in the open position.

(4) The bleeder valve shall be checked to ensure that it is not plugged and is functioning properly.

(5) Any leakage through the bleeder valve shall require a re-evaluation of the job before work continues.

(6) Discharge of leakage through the bleeder valve shall be directed so as not to create a hazard if the block valve fails.

(7) Before the double block valve(s) is opened, a qualified person shall determine that it is safe.

(b) Cold water, air and foam lines need not be blinded or disconnected, but shall be provided with block valves.

(c) Blinds shall be of sufficient strength and so installed as to provide safe conditions of pressure, temperature and service.

(d) Lines which are blinded shall be clearly identified.

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


1. Amendment of section heading and text and new NOTE filed 9-6-94; operative 10-6-94 (Register 94, No. 36).

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