CSLB C-27 Landscaping ContractorSite Preparation and DrainageMedium

A landscape contractor is excavating a trench for a new drainage pipe. The trench is 3 feet deep, and the soil is stable. According to Cal/OSHA regulations, which of the following protective systems is required for this excavation?

  1. ANo protective system is specifically required
  2. BSloping or benching the trench walls
  3. CShielding (trench box) the workers
  4. DShoring the trench walls
Show answer & explanation

Correct answer: A. No protective system is specifically required

Cal/OSHA regulations (8 CCR 1541.1(a)(1)) state that each employee in an excavation shall be protected from cave-ins by an adequate protective system, *except* when excavations are made entirely in stable rock or when they are less than 5 feet in depth and examination by a competent person provides no indication of a potential cave-in. Since the trench is 3 feet deep and the soil is stable, no protective system is specifically required.

Why the other options are wrong

  • B. Sloping or benching is a protective system, but not required for trenches less than 5 feet deep in stable soil.
  • C. Shielding (trench box) is a protective system, but not required for trenches less than 5 feet deep in stable soil.
  • D. Shoring is a protective system, but not required for trenches less than 5 feet deep in stable soil.

Cal/OSHA Trench < 5ft (Stable Soil)

Cal/OSHA does not specifically require a protective system for excavations less than 5 feet deep if a competent person determines there is no indication of a potential cave-in and the soil is stable.

  • Applies to trenches less than 5 feet deep.
  • Requires a competent person's assessment.
  • Protective systems are mandatory for deeper or unstable excavations.

Memory trick: Five feet is the 'safe' depth line.

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