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Subchapter 4. Construction Safety Orders
Article 37. Confined Spaces in Construction (Refs & Annos)
(a) Before it begins work at a worksite, each employer shall ensure that a competent person identifies all confined spaces in which one or more of the employees it directs may work, and identifies each space that is a permit space, through consideration and evaluation of the elements of that space, including testing as necessary.
(b) If the workplace contains one or more permit spaces, the employer who identifies, or who receives notice of, a permit space shall:
(1) Inform exposed employees by posting danger signs or by any other equally effective means, of the existence and location of, and the danger posed by, each permit space; and NOTE to Section 1952(b)(1): A sign reading “DANGER -- PERMIT-REQUIRED CONFINED SPACE, DO NOT ENTER” or using other similar language would satisfy the requirement for a sign.
(2) Inform, in a timely manner and in a manner other than posting, its employees' authorized representatives and the controlling contractor of the existence and location of, and the danger posed by, each permit space.
(c) Each employer who identifies, or receives notice of, a permit space and has not authorized employees it directs to work in that space shall take effective measures to prevent those employees from entering that permit space, in addition to complying with all other applicable requirements of this standard.
(d) If any employer decides that employees it directs will enter a permit space, that employer shall have a written permit space program that complies with Section 1953 implemented at the construction site. The written program shall be made available prior to and during entry operations for inspection by employees and their authorized representatives.
(e) An employer may use the alternate procedures specified in Section 1952(e)(2) for entering a permit space only under the conditions set forth in Section 1952(e)(1).
(1) An employer whose employees enter a permit space need not comply with Sections 1953 through 1955 and Sections 1957 through 1960, provided that all of the following conditions are met:
(A) The employer can demonstrate that all physical hazards in the space are eliminated or isolated through engineering controls so that the only hazard posed by the permit space is an actual or potential hazardous atmosphere;
(B) The employer can demonstrate that continuous forced air ventilation alone is sufficient to maintain that permit space safe for entry, and that, in the event the ventilation system stops working, entrants can exit the space safely;
(C) The employer develops monitoring and inspection data that supports the demonstrations required by Section 1952(e)(1)(A) and (e)(1)(B);
(D) If an initial entry of the permit space is necessary to obtain the data required by Section 1952(e)(1)(C), the entry is performed in compliance with Sections 1953 through 1960;
(E) The determinations and supporting data required by Section 1952(e)(1)(A), Section 1952(e)(1)(B), and Section 1952(e)(1)(C) are documented by the employer and are made available to each employee who enters the permit space under the terms of Section 1952(e) or to that employee's authorized representative; and
(F) Entry into the permit space under the terms of Section 1952(e)(1) is performed in accordance with the requirements of Section 1952(e)(2).
NOTE to Section 1952(e)(1): See Section 1952(g) for reclassification of a permit space after all hazards within the space have been eliminated.
(2) The following requirements apply to entry into permit spaces that meet the conditions set forth in Section 1952(e)(1):
(A) Any conditions making it unsafe to remove an entrance cover shall be eliminated before the cover is removed.
(B) When entrance covers are removed, the opening shall be immediately guarded by a railing, temporary cover, or other temporary barrier that will prevent an accidental fall through the opening and that will protect each employee working in the space from foreign objects entering the space.
(C) Before an employee enters the space, the internal atmosphere shall be tested, with a calibrated direct-reading instrument, for oxygen content, for flammable gases and vapors, and for potential toxic air contaminants, in that order. Any employee who enters the space, or that employee's authorized representative, shall be provided an opportunity to observe the pre-entry testing required by subsection (e).
(D) No hazardous atmosphere is permitted within the space whenever any employee is inside the space.
(E) Continuous forced air ventilation shall be used, as follows:
1. An employee shall not enter the space until the forced air ventilation has eliminated any hazardous atmosphere;
2. The forced air ventilation shall be so directed as to ventilate the immediate areas where an employee is or will be present within the space and shall continue until all employees have left the space;
3. The air supply for the forced air ventilation shall be from a clean source and shall not increase the hazards in the space.
(F) The atmosphere within the space shall be continuously monitored unless the entry employer can demonstrate that equipment for continuous monitoring is not commercially available or periodic monitoring is sufficient. If continuous monitoring is used, the employer shall ensure that the monitoring equipment has an alarm that will notify all entrants if a specified atmospheric threshold is achieved, or that an employee will check the monitor with sufficient frequency to ensure that entrants have adequate time to escape. If continuous monitoring is not used, periodic monitoring is required. All monitoring shall ensure that the continuous forced air ventilation is preventing the accumulation of a hazardous atmosphere. Any employee who enters the space, or that employee's authorized representative, shall be provided with an opportunity to observe the testing required by subsection (e)(2)(F).
(G) If a hazard is detected during entry:
1. Each employee shall leave the space immediately;
2. The space shall be evaluated to determine how the hazard developed; and
3. The employer shall implement measures to protect employees from the hazard before any subsequent entry takes place.
(H) The employer shall ensure a safe method of entering and exiting the space. If a hoisting system is used, it shall be designed and manufactured for personnel hoisting; however, a job-made hoisting system is permissible if it is approved for personnel hoisting by a registered professional engineer, in writing, prior to use.
(I) The employer shall verify that the space is safe for entry and that the pre-entry measures required by Section 1952(e)(2) have been taken, through a written certification that contains the date, the location of the space, and the signature of the person providing the certification. The certification shall be made before entry and shall be made available to each employee entering the space or to that employee's authorized representative.
(f) When there are changes in the use or configuration of a non-permit confined space that might increase the hazards to entrants, or some indication that the initial evaluation of the space may not have been adequate, each entry employer shall have a competent person reevaluate that space and, if necessary, reclassify it as a permit-required confined space.
(g) A space classified by an employer as a permit-required confined space may only be reclassified as a non-permit confined space when a competent person determines that all of the applicable requirements in Section 1952(g)(1) through (g)(4) have been met:
(1) If the permit space poses no actual or potential atmospheric hazards and if all hazards within the space are eliminated or isolated without entry into the space (unless the employer can demonstrate that doing so without entry is infeasible), the permit space may be reclassified as a non-permit confined space for as long as the non-atmospheric hazards remain eliminated or isolated;
(2) The entry employer shall eliminate or isolate the hazards without entering the space, unless it can demonstrate that this is infeasible. If it is necessary to enter the permit space to eliminate or isolate hazards, such entry shall be performed under Sections 1953 through 1960. If testing and inspection during that entry demonstrate that the hazards within the permit space have been eliminated or isolated, the permit space may be reclassified as a non-permit confined space for as long as the hazards remain eliminated or isolated;
NOTE to Section 1952(g)(2): Control of atmospheric hazards through forced air ventilation does not constitute elimination or isolation of the hazards. Section 1952(e) covers permit space entry where the employer can demonstrate that forced air ventilation alone will control all hazards in the space.
(3) The entry employer shall document the basis for determining that all hazards in a permit space have been eliminated or isolated, through a certification that contains the date, the location of the space, and the signature of the person making the determination. The certification shall be made available to each employee entering the space or to that employee's authorized representative; and
(4) If hazards arise within a permit space that has been reclassified as a non-permit space under Section 1952(g), each employee in the space shall exit the space. The entry employer shall then reevaluate the space and reclassify it as a permit space as appropriate in accordance with all other applicable provisions of this standard.
(h) Permit Space Entry Communication and Coordination.
(1) Before entry operations begin, the host employer shall provide the following information, if it has it, to the controlling contractor:
(A) The location of each known permit space;
(B) The hazards or potential hazards in each space or the reason it is a permit space; and
(C) Any precautions that the host employer or any previous controlling contractor or entry employer implemented for the protection of employees in the permit space.
(2) Before entry operations begin, the controlling contractor shall:
(A) Obtain the host employer's information about the permit space hazards and previous entry operations; and
(B) Provide the following information to each entity entering a permit space and any other entity at the worksite whose activities could foreseeably result in a hazard in the permit space:
1. The information received from the host employer;
2. Any additional information the controlling contractor has about the subjects listed in Section 1952(h)(1); and
3. The precautions that the host employer, controlling contractor, or other entry employers implemented for the protection of employees in the permit spaces.
(3) Before entry operations begin, each entry employer shall:
(A) Obtain all of the controlling contractor's information regarding permit space hazards and entry operations; and
(B) Inform the controlling contractor of the permit space program that the entry employer will follow, including any hazards likely to be confronted or created in each permit space.
(4) The controlling contractor and entry employer(s) shall coordinate entry operations when:
(A) More than one entity performs permit space entry at the same time; or
(B) Permit space entry is performed at the same time that any activities that could foreseeably result in a hazard in the permit space are performed.
(5) After entry operations:
(A) The controlling contractor shall debrief each entity that entered a permit space regarding the permit space program followed and any hazards confronted or created in the permit space(s) during entry operations;
(B) The entry employer shall inform the controlling contractor in a timely manner of the permit space program followed and of any hazards confronted or created in the permit space(s) during entry operations; and
(C) The controlling contractor shall apprise the host employer of the information exchanged with the entry entities pursuant to subsection (h)(5).
NOTE to Section 1952(h): Unless a host employer or controlling contractor has or will have employees in a confined space, it is not required to enter any confined space to collect the information specified in Section 1952(h).
(i) If there is no controlling contractor present at the worksite, the requirements for, and role of, controlling contactors in Section 1952 shall be fulfilled by the host employer or other employer who arranges to have employees of another employer perform work that involves permit space entry.