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Well, Do You Know the Standards?

By David H. Glabe, P.E. / September 1, 2004

Last month we offered a quiz for you to take to test your knowledge of the OSHA scaffold standards.  Well, here’s the answers.  As you recall, it was suggested that the quiz be taken two ways, one closed book, the other open book.  The purpose was to simulate answering the questions in the field without any reference as opposed to having a source of information readily available.  Let’s see how you did.  Note:  The questions are in italics.

True or False

  1. A suspended scaffold shall be designed by a competent person.  False; a suspended scaffold shall be designed by a qualified person.  (If you don’t know the definition of a qualified person, look it up in the definitions of the scaffold standard.) (29 CFR 1926.451(a)(6)) and (29 CFR 1926.450–Definitions
  2. All suspended scaffolds must have at least a 3 to 1 safety factor.  False; all suspended scaffolds shall have at least a 4 to 1 safety factor. (29 CFR 1926.451(a)(1))
  3. Counterweights for suspended scaffolds must have a 4 to 1 safety factor.  True.  (29 CFR 1926.451(a)(2))
  4. Suspension ropes for suspended scaffolds must be steel.  False; while many suspension ropes are steel, the only requirement is that the ropes have a safety factor of at least 6 unless the safety factor is based on the stall load of the hoist being used.  In that case, the minimum safety factor is 2. (29 CFR 1926.451(a)(3 and 4))
  5. The material used to make suspension ropes for suspended scaffolds must be certified by the American Wire Rope Association.  False; it is the responsibility of the competent person to determine the adequacy and condition of the suspension rope. (29 CFR 1926.451(d)(10) and (29 CFR 1926.451(f)(3))
  6. Counterweights for suspended scaffold outrigger beams can be sand if it is in a sealed container.  True, provided you can guarantee that it won’t leak!  Solid steel counterweights, purposely manufactured for use with outrigger systems, with provisions for positive mechanical attachment, and the weight marked, are strongly recommended.  Furthermore, the counterweights must be “specifically designed as counterweights.” (29 CFR 1926.451(d)(3)(ii, iii, and iv))
  7. Masons multi-point scaffolds can use counterweights provided they are non-flowable material.  False; counterweights cannot be used with masons’ multi-point scaffolds.  Only direct connections can be used with masons’ multi-point scaffolds.  Furthermore, the direct connections for masons’ multi point scaffolds shall be designed by “an engineer experienced in such design.” (1926.451(d)(3)(i))
  8. Tieback cables shall be at least as half as strong as the suspension rope.  False; the tieback rope shall be equal in strength to the suspension rope. (1926.451(d)(3)(vii))
  9. Outrigger beams can never extend more than 48 inches beyond the fulcrum unless designed by a qualified person.  False; first, OSHA does not specify a minimum or maximum allowable cantilever length.  Second, all scaffolds shall be designed by a qualified person, regardless of the cantilever.  In other words, the cantilever can be any length but it shall be designed by a qualified designer (see Question # 1 above).  (29 CFR 1926.451(a)(6))
  10. Repaired wire rope can be used as a suspension rope if it has been repaired by a certified wire rope repairer.  False; is there such a thing as a certified wire rope repairer?  Repaired ropes (wire or otherwise) cannot be used as suspension ropes. (1926.451(d)(7))
  11. Ropes shall be inspected for defects by a competent person prior to each work shift. True.  (29 CFR 1926.451(d)(10))
  12. U-bolts can be used on scaffold suspension wire ropes provided they are tight.  False; U-bolts “shall not be used at the point of suspension for any scaffold hoist.”  (29 CFR 1926.451(d)(12)(v))
  13. There shall be at least three wire rope clips used on wire ropes at their connection points.  True.  (29 CFR 1926.451(d)(12)(i))
  14. Manually operated hoists shall require a positive crank force to descend.  True.  (29 CFR 1926.451(d)(17))
  15. Once the rigging system has been installed and inspected, it shall be inspected weekly unless the system has been overloaded.  False; “The ropes shall be inspected for defects by a competent person prior to each workshift and after every occurrence which could affect a rope’s integrity.” Besides, the rigging system should never be overloaded! (29 CFR 1926.451(d)(10))
  16. Personal Fall Arrest Equipment shall be used on all multi-point suspended scaffolds.  False; either a guardrail system or personal fall arrest system shall be used on a multi-point suspended scaffold.  (29 CFR 1926.451(g)(1)(vii))
  17. When vertical lifelines are used on a single level, two point suspended scaffold, the lifeline shall be attached to a secure location on the scaffold.  False; vertical lifelines should never be attached to a single level, two point suspended scaffold. (29 CFR 1926.451(g)(3)(i))
  18. Trained and experience workers do not have to use personal fall protection on two point suspended scaffolds if there is a guardrail system.  False; all employees on a two point suspended scaffold shall use personal fall protection and a guardrail system.  Training and experience alone do not stop falls!  (29 CFR 1926.451(g)(1)(ii))
  19. Suspended scaffold hoist operators need more training than other workers on a suspended scaffold platform.  True; if you are going to operate the hoist, you need to know how to.  If you aren’t going to operate the hoist, if can be argued that you don’t have to learn how.  (29 CFR 1926.454)
  20. While a good idea, a retrieval plan for dangling workers is not required on a suspended scaffold platform that is designed by a qualified person.  False; a qualified person has nothing to do with it.  If you marked true, you need some serious retraining! (29 CFR 1926.454 and (29 CFR 1926.502(d)(20))
  21. Platforms on two-point suspended scaffolds can never be more than 36 inches wide.  False; “Platforms shall not be more than 36 inches (94 cm) wide unless designed by a qualified person to prevent unstable conditions.”  (29 CFR 1926.452(p)(1))
  22. Welders working from a suspended scaffold should be concerned about special requirements for protecting the rigging.  True; Welding current can arc through the suspension wire rope and other strange things can occur.  (29 CFR 1926.451(d)(17)(i – vi))
  23. Suspended scaffold erectors do not have to use personal fall arrest equipment unless the building is more than 5 stories (48 feet) tall.  False; fall protection on all scaffolds, including suspended, is required at 10 feet (3.1m).  If you marked true, you really need retraining! (29 CFR 1926.451(g)(1))
  24. If u-bolts are used on suspension ropes, there shall be at least 4 so that there is a 4 to 1 safety factor.  False; there is no direct correlation between the number of U-bolts and a safety factor of 4.  Besides, U-bolts “shall not be used at the point of suspension for any scaffold hoist.”  See question # 12 above.  (29 CFR 1926.451(d)(12)(v))
  25. All suspended scaffolds, single, two-point, and multi-point, shall have a guardrail system.  True; single and two point suspended scaffold users shall also use personal fall arrest systems.  (29 CFR 1926.451(g)(1)(ii and vii))
  26. Outrigger beams used for a mason’s multi-point suspended scaffold shall be designed by an engineer experienced in such scaffold design.  False; specifically, the “connections shall be designed by an engineer experienced in such scaffold design.”  However, it’s a good idea to have the entire system designed by a qualified engineer.  See question # 7 above.  (29 CFR 1926.451(d)(3)(i))
  27. Suspension ropes shall be replaced if more than 6 randomly distributed wires in one rope lay are broken.  True.  (29 CFR 1926.451(d)(10)(iii))
  28. Only power operated hoists that support two or more workers require an overspeed brake.  False; both power operated and manually operated hoists “shall have a braking device or locking pawl which engages automatically….”  The number of workers on the scaffold has nothing to do with it.  (29 CFR 1926.451(d)(16))
  29. Manually operated hoists can “free-fall” if the operator is trained in this type of operation.  False.  Operator training has nothing to do with it.  Manually operated hoist shall not be allowed to free fall.  (29 CFR 1926.451(d)(17))
  30.  While erectors shall have special training, users of suspended scaffolds do not require specialized training on the use of suspended scaffolds if they are experienced.  False; while erectors shall have additional training on the proper installation of suspended scaffolds, users shall have training in the operation, use, inspection, and maintenance of suspended scaffolds, as required by the training standards and their employer’s requirements. Experience only counts if they have had proper training.  (29 CFR 1926.454)
  31. The SIA can provide erectors and users of suspended scaffolds with a recognized training program.  True.  Contact the SIA for more information: 818-610-0320.

 

Fill in the blank:

  1. All suspended scaffolds shall be inspected by a competent person. (29 CFR 1926.451(d)(10) and (29 CFR 1926.451(f)(3))
  2. A scaffold supported by a wire rope is classified as a suspended scaffold.  (29 CFR 1926.450-Definitions)
  3. When a u-bolt is used, the u-bolt shall be placed over the dead end of the rope.  (29 CFR 1926.451(d)(12)(vi))  Note:  U-bolts cannot be used “at the point of suspension for any scaffold hoist.  (29 CFR 1926.451(d)(12)(v))  Also see questions # 12 & 24 above.
  4. A minimum of  3 wire rope clips shall be used on suspended scaffold connections.  (29 CFR 1926.451(d)(12)(i))

 

This leaves us with the last question of the quiz:

  1. I think I got ________ of the questions correct.

 

If you got this one correct, congratulations!  If you got it wrong, watch out!  Here’s the reason.  Even if you answered 0 on question # 36 you at least realized you shouldn’t guess and/or make up some answer.  On the other hand, if you answered 36 and did not get all the answers correct, then you are misleading yourself and more importantly, misleading other employees.  Whether you’re an erector, safety director, enforcement officer, or scaffold user, it makes no difference; the standards should be cited correctly and accurately.  Thinking you are right when you are not will cause confusion at best, and injuries at worst.  Don’t take chances—know and understand the standards.

Tags: Scaffolding Scaffolding Platforms counterweights for suspended scaffolds Hoists manually operated hoists multi-point scaffolds OSHA Standards & Regulations outrigger beams Resources suspended scaffold standards suspension ropes for suspended scaffolds tieback cables vertical lifelines

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