Kept in Suspension

By David H. Glabe, P.E. / February 1, 2009

A review of the standards proves that using a suspended scaffold, such as a two point suspension scaffold typically used for high rise building maintenance and repairs, isn’t any more dangerous than walking down the street that is below it.  In fact, I surmise that a perusal of statistics will show that walking down the street is probably more hazardous than working on a suspended scaffold.  Check out the standards; suspension ropes have to be six times stronger than the load that will be on them.  How can these ropes possibly break?  Obviously somebody is misbehaving.  Is it you?  How well do you know the standards?  Here is a quiz to test your understanding of the federal OSHA standards regarding suspended scaffolds, those scaffold platforms supported by ropes or other non-rigid means.  (Do you suppose the workers who installed the suspended scaffold in the photo would ace this quiz?)

True or False:

  1. The minimum safety factor for suspended scaffold components is 6.
  2. It is permissible to use u-bolts for rope connections supporting workers as long as there are at least three u-bolts.
  3. Outrigger beams can only stick out from the face of the building 24 inches.
  4. Multi-point suspended scaffold users are not required to utilize personal arrest equipment in addition to a guardrail system.
  5. All workers on a multi-level two point suspended scaffold must wear personal fall arrest equipment and be tied off to individual vertical lifelines.
  6. An adjustable scaffold is a suspension scaffold if the mechanical back-up anti-fall dog (level) is inoperable.
  7. All suspended scaffold platform users suspended over water must have life preservers.
  8. All suspended scaffold platform users suspended over water must have at least one lifesaving skiff.
  9. Counterweights for cantilever beams can be water, if frozen, or Jello®.
  10. Counterweights shall not be removed from the beam until the scaffold is disassembled.

Fill in the blank:

  1. All outrigger beams not stabilized by direct connections shall be secured by ________.
  2. When wire rope clips are used on suspension scaffolds, there shall be a minimum number of _________ clips per connection.
  3. Suspension scaffolds shall be inspected before each __________ by a ________ person.
  4. Two point suspension scaffold platforms shall be no more than ________ inches wide unless designed by a qualified person.
  5. The toprail height on a two point suspended scaffold shall be between ______ inches and ________ inches.
  6. The toprail strength on a two point suspended scaffold shall be at least _____ pounds.
  7. All suspended scaffold users shall be trained by a __________ person.
  8. The minimum anchor strength for the personal fall arrest anchor is _______ pounds unless designed by a ___________ person and maintains a safety factor of at least _______.
  9. If an outrigger beam cantilevers 24 inches beyond the fulcrum and the centerline of the counterweight is 12 feet behind the fulcrum, and the load on the suspension rope is 1,000 pounds, the counterweight must be ___________ pounds.
  10. All suspended scaffold installations must be done under the supervision of a _______ person _______ in scaffold erection, using _________and ___________ persons.
  11. Counterweights shall be secured by a _____________ means to the outrigger beam to prevent accidental displacement.

The answers are on page xxxx.  There is no pressure here but remember: you pass if you get all the answers correct and you fail if you get from 1 to 21 wrong; OSHA doesn’t permit partial compliance!


  1. F
  2. F
  3. F
  4. T
  5. F
  6. T
  7. T
  8. T
  9. F
  10. T
  12. 3
  14. 36
  15. 36 AND 45
  16. 100
  18. 5000, QUALIIED
  19. 667 POUNDS

Tags: Scaffolding cantilever beam OSHA safety OSHA Standards & Regulations Resources Safety Hazards scaffold suspended scaffold

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David H. Glabe, P.E.

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