According to the Bureau of Labor Statistics falls remain the number one killer of workers in the construction industry and the number two killer of workers in private industry. One of the most likely ways to prove those statistics true is to look at the number of falls from scaffolding. This problem was so prevalent for such a long time, that it prompted OSHA to revise their standards on scaffold safety in the late 1980s.
The standard that OSHA devised has been periodically updated; but it still contains several key provisions:
- Fall protection or fall arrest systems-Each employee more than 10 feet above a lower level must be protected from falls by guardrails or a fall arrest system. However, employees on single-point and two-point adjustable suspension scaffolds must have both.
- Guardrail height-The height of the toprail for scaffolds manufactured and placed in service after January 1, 2000 must be between 38 inches and 45 inches.
- Crossbracing-When the crosspoint of crossbracing is used as a toprail, it must be between 38 inches and 48 inches above the work platform.
- Midrails- Midrails must be installed approximately halfway between the toprail and the platform surface. When a crosspoint of crossbracing is used as a midrail, it must be between 20 inches and 30 inches above the work platform.
- Footings-Support scaffold footings must be level and capable of supporting the loaded scaffold. The legs, poles, frames, and uprights must be placed on base plates and mudsills.
- Platforms-Supported scaffold platforms must be fully planked or decked.
- Guying ties, and braces-Supported scaffolds with a height-to-base of more than 4:1 have to be restrained from tipping by guying, tying or bracing.
- Capacity-Scaffolds and scaffold components must support at least 4 times the maximum intended load. Suspension scaffold rigging must support at least 6 times the intended load.
In addition to complying with OSHA requirements for the design and construction of scaffolds, employers need to follow other scaffolding safety practices. They must ensure that scaffold suspension ropes and body belt or harness system droplines are shielded from heat-producing processes such as welding, hot acids or other corrosive substances, or cut by sharp edges or abrasions. Ropes should be made from material that is not affected by heat or by acids or other corrosives.
All scaffolds and scaffold components should be inspected before each use to ensure that structurally sound portions of buildings or structures are used to anchor droplines for body belt, harness systems, and tiebacks for suspension scaffold support devices. Droplines and tiebacks should be secured to separate anchor points.
Employees should be provided with appropriate fall protection systems and understand how to use them correctly. Generally, workers should be protected by a Type I guardrail system or a combination of body belt or harness system with a Type II guardrail system. The Type I guardrail systems are capable of providing the necessary fall protection without the use of body belts. Where the Type II guardrail systems accentuate the scaffold edge, restrain movement, provide handholds, and prevent wrong moves, they still must be supplemented by body belt or harness systems to provide the necessary fall protection.
The requirements differ when single-point and two-point adjustable suspension scaffolds are used. Workers must be protected by both a body belt or harness system and a Type I or Type II guardrail system. If boatswain chairs, catenary scaffolds or float scaffolds are used, workers only have to be protected by a body belt or harness system.