CSLB General Building (B)Site Work, Foundations and ConcreteMedium
A trench is being excavated to a depth of 8 feet. Per OSHA/Cal-OSHA excavation safety standards, how far from the edge of the excavation must excavated soil (spoil) be placed?
- AAt least 4 feet from the edge
- BAt least 1 foot from the edge
- CSpoil may be piled directly at the edge if compacted
- DAt least 2 feet from the edge
Show answer & explanationAnswer & explanation
Correct answer: D. At least 2 feet from the edge
OSHA and Cal-OSHA require excavated material (spoil) to be kept at least 2 feet back from the edge of a trench or excavation to prevent it from sliding or rolling back into the excavation and endangering workers.
Why the other options are wrong
- A. 4 feet is more than required, though not prohibited.
- B. 1 foot does not provide sufficient setback to prevent material from falling in.
- C. Piling spoil at the edge creates a serious cave-in and fall hazard regardless of compaction.
Spoil Pile Setback
Excavated soil and other materials must be kept at least 2 feet from the edge of a trench to prevent them from falling back into the excavation.
- 2-foot minimum setback required by OSHA/Cal-OSHA
- Applies to spoil, equipment, and materials
- Reduces risk of cave-in from surcharge loading
Memory trick: Two feet back keeps the dirt off your back.