WITH VERIFIED SOLUTIONS LATEST UPDATE – CURRENT YEAR
SECTION 1: OSHA Safety Regulations (Questions 1–50)
1. OSHA 1926 – Excavations
Question: According to OSHA 1926 Subpart P, what is the maximum allowable
slope for Type A soil?
o A) 1:1 (45°)
o B) 1.5:1 (34°)
o C) 2:1 (26°)
o D) 3:1 (18°)
Correct Answer: B) 1.5:1 (34°)
Rationale: OSHA 1926 Subpart P classifies soils. Type A soil (clay, silty clay) has the
highest stability and allows a 1.5:1 slope. Type B is 1:1, Type C is 1.5:1. This is one
of the most tested topics on the GF-9 exam – know soil types and slope
requirements.
2. Trenching – Competent Person
Question: Who is responsible for inspecting a trench before workers enter?
o A) The foreman
o B) The competent person
o C) The project manager
, o D) The safety officer
Correct Answer: B) The competent person
Rationale: OSHA defines a "competent person" as someone capable of identifying
hazards and authorized to take corrective action. The competent person must
inspect trenches daily and after any rain or disturbance. This is a heavily tested
concept.
3. Trenching – Protective Systems
Question: Which of the following is NOT an acceptable protective system for a
trench over 5 feet deep?
o A) Sloping
o B) Benching
o C) Shoring
o D) Leaving the trench open without support
Correct Answer: D) Leaving the trench open without support
Rationale: OSHA requires protective systems for trenches 5 feet or deeper. Sloping,
benching, shoring, and shielding (trench boxes) are all acceptable. Leaving an
unsupported trench is a violation.
4. Trench Box – Installation
Question: When using a trench box, how far above the trench bottom must the box
extend?
o A) 6 inches
o B) 12 inches
, o C) 18 inches
o D) 24 inches
Correct Answer: C) 18 inches
Rationale: A trench box must extend at least 18 inches above the trench bottom to
prevent soil from falling in. This is a specific OSHA requirement that frequently
appears on the exam.
5. Excavation – Access/Egress
Question: In a trench 4 feet deep, how far apart must ladders or other means of
egress be placed?
o A) 25 feet
o B) 50 feet
o C) 75 feet
o D) 100 feet
Correct Answer: B) 50 feet
Rationale: OSHA requires ladders, ramps, or stairs in trenches 4 feet or
deeper, spaced no more than 50 feet apart so workers can exit quickly in an
emergency.
6. Trenching – Soil Testing
Question: Which test is used to determine soil type in the field?
o A) Plasticity test
o B) Thumb penetration test
, o C) Pocket penetrometer
o D) All of the above
Correct Answer: D) All of the above
Rationale: Field tests for soil classification include plasticity, thumb penetration,
pocket penetrometer, and dry strength tests. The competent person must perform
these tests daily.
7. Soil Classification – Type C
Question: Which soil type is the least stable and requires the flattest slope (1.5:1)?
o A) Type A
o B) Type B
o C) Type C
o D) Type D
Correct Answer: C) Type C
Rationale: Type C soil (gravel, sand, loamy sand, or submerged soil) is the least
stable. Type C requires a 1.5:1 slope (34°). This is a common exam question.
8. Trenching – Water Accumulation
Question: If water accumulates in a trench, what must be done?
o A) Continue working and pump it out later.
o B) Remove workers immediately and implement dewatering.
o C) Wait for the water to evaporate.
o D) Add gravel to absorb the water.