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Standard Interpretations
01/02/2002 - Clarification of requirements for construction scaffold erection/dismantling; safe means of access; blocks for two-point suspension scaffolds. |
Standard Interpretations - Table of Contents |
January 2, 2002 Ms. Carmen Shafer Assistant Director of Safety and Health The Associated General Contractors of America AGC B Indiana 1050 Market Tower 10 West Market Street Indianapolis, IN 46204 Re: 1926.451(a)(3), (a)(4), (b)(1)(i), (c)(1)(iii), (d)(16), (d)(17), (f)(3), (e), (e)(9)(i), (e)(9)(ii), (e)(9)(iii), (e)(9)(iv), (g)(1), (g)(4)(i), 1926.452(p)(3), 1926.550(g) Dear Ms. Shafer: This letter is in response to your May 11, 2001, letter to the U.S. Department of Labor - Occupational Safety and Health Administration (OSHA) in which you ask a number of questions requesting clarification of several provisions of OSHA's construction scaffold standard (29 CFR Part 1926, Subpart L - Scaffolds). We have paraphrased your questions below. Please note that a State that administers its own occupational safety and health plan under Section 18 of the Occupational Safety and Health Act of 1970, as does Indiana, is required to have standards that "are or will be at least as effective inproviding safe and healthful employment and places of employment as" OSHA standards. In addition, a State may enact more stringent occupational safety and health requirements. For this reason, it is important to keep abreast of current changes in your State's plan. Since Indiana employers must comply with Indiana requirements and those may be more stringent than those of OSHA, we suggest you contact the Indiana Department of Labor, Indiana Occupational Safety and Health Division (IOSHA) Section of Construction Safety at its website: http://www.state.in.us/labor/iosha/iosha.html. This letter will not discuss Indiana plan standards. Background: On August 30, 1996, OSHA published revised safety standards for scaffolds used in construction (Federal Register Vol. 61, No. 170). This revision updated standards and set performance-oriented criteria, where possible, to protect employees from scaffold-related hazards such as falls, falling objects, structural instability, electrocution and overloading. Part 1926 of 29 CFR Subpart L sets forth requirements for all scaffolds used in construction (which includes alteration, repair, and demolition covered under Part 1926), except that crane- or derrick- suspended personnel platforms continue to be covered under §1926.550(g). Question 1: Would moving work platforms, (including outriggers (buck boards), or scaffold planking) from a second level to higher levels be considered erection and dismantling requiring employers to comply with Subpart L's §1926.451(e)(9)(i) and (iii)? The following terms are defined in the standard: Outrigger: "The structural member of a supported scaffold used to increase the base width of a scaffold in order to provide support for and increased stability of the scaffold." Outrigger beam (Thrustout): "The structural member of a suspension scaffold or outrigger scaffold which provides support for the scaffold by extending the scaffold point of attachment to a point out and away from the structure or building." Outrigger scaffold: "A supported scaffold consisting of a platform resting on outrigger beams (thrustouts) projecting beyond the wall or face of the building or structure, the inboard ends of which are secured inside the building or structure." Section 1926.451 includes two additional concepts necessary to answering your question. Section 1926.451(b)(1)(i) states that: "Each platform unit (e.g., scaffold plank, fabricated plank, fabricated deck, or fabricated platform) shall be installed so that the space between adjacent units and the space between the platform and the uprights is no more than 1 inch (2.5 cm) wide, except where the employer can demonstrate that a wider space is necessary (for example, to fit around uprights when side brackets are used to extend the width of the platform)." Section 1926.451(c)(1)(iii) states: "Ties, guys, braces, or outriggers shall be used to prevent the tipping of supported scaffolds in all circumstances where an eccentric load, such as a cantilevered work platform, is applied or is transmitted to the scaffold." "Buck-boards" which you use in apposition to "outriggers" is not defined in Part 1926 Subpart L. Consequently, this discussion is limited to the definitions and terms found in 1926 Subpart L. Section 1926.451(e) applies to scaffold access for all employees. Access requirements for employees erecting or dismantling supported scaffolds are specifically addressed in paragraph (e)(9). Work platforms, including side bracket, cantilevered and their scaffold planking, are types of scaffold components/parts. Therefore, moving, altering, removing, reassembling or reconstructing scaffold components/parts is considered part of the erection and dismantling processes, requiring employers to comply with the provisions of §1926.451(e)(9) introductory text and (i) through (iv). Question 2: What does "a safe means of access" mean as it applies to §1926.451(e)(9)(i)? Section 1926.451(e) sets the requirements for access to supported scaffolds for all employees and indicates that access requirements "for employees erecting or dismantling supported scaffolds" are found in Subsection (e)(9). Paragraph (e)(1) sets general requirements for safe access for a differential of "more than 2 feet above or below a point of access." Paragraph 1926.451(e)(9)(i) requires that employers provide a safe means of access for each employee erecting or dismantling a supported scaffold "where the provision of safe means of access is feasible and does not create a greater hazard." It further requires the employer to have a "competent person determine whether it is feasible or would pose a greater hazard to provide, and have employees use, a safe means of access. This determination shall be based on site conditions and the type of scaffold being erected or dismantled." "Safe means of access" is not specifically defined in the standard; however, the goal of §1926.451(e)(9) is to eliminate or minimize exposure for employees erecting or dismantling supported scaffolds to access hazards. The principles of safe access by climbing are reflected in the parts of §1926.451 that set specific access requirements for other circumstances, and in Part 1926 Subpart X. In general, those principles include adequate hand-holds, and stepping surfaces that are: (1) level or will allow workers to maintain their balance; (2) sufficiently close to one another so that workers can move from one to the next without falling; (3) spaced evenly enough so that the workers can find the next stepping surface without seeing it while ascending and descending; and (4) sufficiently strong and stable. Personnel positioning equipment such as aerial lifts are also a means of safe access. Question 3: Section 1926.451(e)(9)(ii) states that: "hook-on or attachable ladders shall be installed as soon as scaffold erection has progressed to a point that permits safe installation and use." Is there one specific point when it is safe to do so? If not, who is responsible for determining when this point occurs? The standard does not specify a particular point in the process at which it is safe to attach and use hook-on or attachable ladders. This is due to variable site conditions and the variety of types and configurations of scaffolds. Under §1926.451(e)(9)(i), the employer is required to "have a competent person determine whether it is feasible or would pose a greater hazard to provide, and have employees use a safe means of access ... based on site conditions and the type of scaffold being erected or dismantled" [emphasis added]. Part of making this assessment involves making the determination set forth in (e)(9)(ii). Therefore, the employer must use a competent person to identify the point at which it is safe to attach and use hook-on or attachable ladders. Question 4: What must the employer do to determine if the scaffold end frames meet the requirements in §1926.451(e)(9)(iii) (end frames used for access)? Are there any types or brands of scaffold frames that do not meet these requirements? As previously discussed in question 2, §1926.451(e)(9)(i) requires that "employers provide a safe means of access for each employee erecting or dismantling a supported scaffold where the provision of safe means of access is feasible and does not create a greater hazard." It further requires the employer to have a "competent person determine whether itis feasible or would pose a greater hazard to provide, and have employees use a safe means of access. This determination shall be ased on site conditions and the type of scaffold being erected or dismantled." Paragraph 1926.451(e)(9)(iii) states: "When erecting or dismantling tubular welded frame scaffolds, (end) frames, with horizontal members that are parallel, level and are not more than 22 inches apart vertically may be used as climbing devices for access, provided they are erected in a manner that creates a usable ladder and provides good hand hold and foot space."Therefore, to use end frames for access, the employer's competent person must first determine that they can handle the loads imposed during access. In making the assessment as to whether they provide a safe means of access, the competent person must also determine if the end frames meet the requirements of §1926.451(e)(9)(iii) for use as a climbing device for safe access. Some masons' scaffolds do not comply with this section. We do not know if there are any specific brands of scaffold frames that fail to meet these requirements. Employers should be additionally aware that under §1926.451(f)(3), "scaffolds and their components shall be inspected for visible defects by a competent person before each work shift, and after any occurrence which could affect a scaffold's structural integrity." Question 5: Do §1926.451(d)(16) and (d)(17) apply to blocks with fiber or synthetic ropes attached to a two-point suspension scaffold that is manually raised and lowered? Yes. The provisions of both §1926.451(d)(16) and (d)(17) pertain to manually operated and power-operated suspension scaffold hoists. Section 1926.451(d)(16) states: "In addition to the normal operating brake, suspension scaffold power-operated hoists and manually operated hoists shall have a braking device or locking pawl which engages automatically when a hoist makes either of the following movements: an instantaneous change in momentum or an accelerated overspeed."Section 1926.451(d)(17) states: "Manually operated hoists shall require a positive crank force to descend." These provisions apply irrespective of the type of suspension rope/cable. The qualified person is not restricted to a certain type of rope as long as the suspension ropes are capable of supporting, without failure, six times the maximum intended load as set forth. Question 6: Are blocks for fiber or synthetic ropes attached to a two-point suspension system that is manually raised and lowered permitted if they are engineered and meet the requirements of applicable standards in §§1926.451 and 1926.452 and Subpart M? Yes. All scaffold systems must be designed by a qualified person in accordance with the provisions in §1926.451 (General Requirements) and §1926.452 (additional requirements applicable to specific types of scaffolds) and constructed and loaded in accordance with those designs. Note that in the general provisions for suspension ropes, §1926.451(a)(4) requires: Each suspension rope, including connecting hardware, used on adjustable suspension scaffolds shall be capable of supporting, without failure, at least 6 times the maximum intended load applied or transmitted to that rope with the scaffold operating at either the rated load of the hoist, or two (minimum) times the stall load of the hoist, whichever is greater.Fall protection requirements for scaffolds are in §1926.451(g)(1) through (4)(ii), which includes references to provisions in Part 1926 Subpart M. With respect to the blocks, note that §1926.452(p)(3) requires that: The blocks for fiber or synthetic ropes shall consist of at least one double and one single block. The sheaves of all blocks shall fit the size of the rope used.If you need additional information, please do not hesitate to contact us by fax at 202-693-1689, or by mail at: Occupational Safety and Health Standard Administration (OSHA) [Directorate of Construction, Standards and Compliance Guidance], Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210. Sincerely, Russell B. Swanson, Director Directorate of Construction |
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