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Subchapter 15. Petroleum Safety Orders--Refining, Transportation and Handling
Article 5. Fire and Explosions

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§6777. Hot Work Procedures and Permits

(a) Scope and application. This section contains the required practices and procedures necessary to protect employees from fire and explosion hazards associated with hot work. This section applies to all hot work operations, except as provided in subsections (a)(1) and (a)(2).
(1) The following operations are exempt from the requirements of this section:
(A) The operation of fixed fired equipment.
(B) Hot work required for operating purposes in laboratories and pilot plants. This exemption does not apply to sources of ignition used in the maintenance of equipment.
(C) Hot work within designated, marked, or posted smoking areas within plants.
(D) Hot work in locations outside of plants where it would be safe to smoke.
(2) The following operations need only comply with the hot work safety procedures in subsections (b), (c), and (d):
(A) Operations where compliance with the order will result in the employer or authorized agent issuing a hot work permit to him/herself.
(B) Operations where the use of a source of ignition in connection with work on an oil or gas transmission pipeline remote from plants does not affect the normal movement of the contents of the pipeline.
(C) Hot work within areas meeting all of the following conditions:
1. With respect to operating process equipment, the area is:
a. Free of flammable liquids, vapors and gases except as may be required for necessary activities when safely used, handled and stored; and
b. Effectively protected against the possibility of flammable oils, liquids, vapors or gases being liberated within the area from pipe lines, sewers, drains or ditches.
2. The area is posted in a manner to define the boundaries.
3. The area has a warning system to alert employees to eliminate ignition sources in the event of an emergency.
(b) Hot work procedures. Before hot work is begun, the employer shall determine that a source of ignition can be safely used. In locations where flammable vapors may be present, precautions shall be taken to prevent ignition by eliminating or controlling sources of ignition. A source of ignition shall not be introduced into an area until all of the following required actions have been completed:
(1) Tests for the presence of flammable gases and vapors shall be made when the concentration of flammable gases or vapors may reasonably be expected to exceed 20 percent of the lower explosive limit (LEL). The tests shall confirm that the concentration of flammable gases and vapors does not exceed 20 percent of the LEL.
(2) Oil accumulations or other combustible materials shall be removed or protected from ignition when present in exposed areas.
(3) The gauge valves shall be closed and the gauges drained, or the gauge glasses shall be guarded when gauge glasses contain flammable liquids, vapors or gases and are exposed to the spatter of molten metal.
(c) A source of ignition shall not be used where the concentration of flammable gases or vapors exceeds 20 percent of the LEL.
(d) Suitable fire extinguishing equipment shall be readily available in the area where hot work is performed.
(e) Hot work permits.
Except for those operations identified in subsection (a)(2), a written and numbered hot work permit shall be completed, signed and issued by the employer or his authorized agent before a source of ignition is used. As part of this hot work permit issuance procedure, the employer shall verify that all of the required actions identified in subsection (b) have been completed before a hot work permit is issued.
(f) Before an employee introduces a source of ignition, the employer shall provide a copy of the hot work permit to the employee or shall post a copy of the permit in the area of the planned hot work. The copy of the permit shall be kept on the job where the source of ignition is being used until the work is completed, or the permit expires or is revoked.
(g) The hot work permit shall contain the following information:
(1) The effective time and date.
(2) The place of use.
(3) The hours during which the source of ignition may be used, not to exceed 24 hours.
(4) The specific location or piece of equipment where the source of ignition will be used.
(5) The nature of the use of the source of ignition.
(6) Any special precautions or limitations to be observed before, during or after the use of the source of ignition, including the need for fire watch.
(h) The employer shall revoke the permit under the following conditions:
(1) When circumstances would make the continued use of the source of ignition hazardous.
(2) Any time the conditions of its issuance change.
(3) Inactivity of permitted hot work in excess of two hours unless test(s) determine the LEL is less than 20%
(i) The employer issuing the hot work permit shall keep a copy of the permit on file at the plant of issue for at least six months after the date of issue.
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).
2. Amendment of section heading and section filed 11-9-2004; operative 12-9-2004 (Register 2004, No. 46).
3. Editorial correction of subsection (b) (Register 2005, No. 44).

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