CHST - Construction Health and Safety Technician Excavation and Trenching Safety Questions and Answers

Question 1

According to 29 CFR 1926 Subpart P, what is the maximum lateral distance a worker may travel within a trench to reach a means of egress?

Accepted Answer

25 feet

Answer

OSHA standard 1926.651(c)(2) requires that a stairway, ladder, ramp, or other safe means of egress be located in trench excavations that are 4 feet or more in depth so as to require no more than 25 feet of lateral travel for employees.

Question 2

A construction site has an 8-foot deep trench dug entirely in Type A soil. The competent person has observed that heavy vehicle traffic is causing vibrations near the trench. Which of the following is the correct action for the competent person to take?

Accepted Answer

Reclassify the soil and adjust the protective system accordingly.

Answer

According to OSHA's soil classification system, a soil cannot be classified as Type A if it is subject to vibration. The competent person must re-evaluate and reclassify the soil, which would likely downgrade it to Type B or C, requiring a change in the protective system (e.g., changing the slope angle or using shoring/shielding).

Question 3

A contractor is excavating a trench that will be 22 feet deep. Which of the following is required for the protective system design?

Accepted Answer

Design by a registered professional engineer.

Answer

OSHA standard 1926.652(c) requires that for excavations 20 feet deep or greater, the protective system must be designed by a registered professional engineer or be based on tabulated data prepared and/or approved by a registered professional engineer.

Question 4

During a daily inspection, a competent person notices water accumulating in the bottom of a 6-foot deep trench. Which of the following is a primary and immediate responsibility of the competent person?

Accepted Answer

Remove exposed employees from the hazardous area.

Answer

Per 1926.651(k)(2), if a competent person finds evidence of a situation that could result in a possible cave-in, such as water accumulation, exposed employees shall be removed from the hazardous area until the necessary precautions have been taken to ensure their safety.

Question 5

Which of the following is a key requirement for storing excavated soil and other materials relative to the trench?

Accepted Answer

They must be placed at least 2 feet from the edge.

Answer

OSHA standard 1926.651(j)(2) requires that employees be protected from excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations. Protection shall be provided by placing and keeping such materials or equipment at least 2 feet from the edge of the excavation.

CHST - Construction Health and Safety Technician Practice Test

CHST - Construction Health and Safety Technician Practice Test

CHST - Construction Health and Safety Technician Excavation and Trenching Safety Questions and Answers