SafetyCâu 92 / 110
An excavation for a sewer lateral is dug to a depth of 6 ft in Type C soil. At what depth does OSHA require protective systems (sloping, shoring, or a trench box) for workers entering the trench?
a.Any depth over 2 ft
b.Any depth over 3 ft
c.Only over 10 ft
d.5 ft or more (and any depth if a competent person sees a hazard)
Giải thích
OSHA requires cave-in protection for any trench 5 ft or deeper, and at any depth if a competent person identifies a hazard, so a 6 ft trench must be sloped, shored, or shielded. Trenches less than 5 ft may be exempt only if a competent person finds no cave-in potential. Soil type sets the required slope angle.
Trích dẫn luật: 29 CFR 1926.652Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- A trench is dug in Type C soil, which OSHA requires to be sloped at 1.5 to 1 (horizontal to vertical). For a trench 8 ft deep, how wide must the sloped opening be beyond the trench bottom on each side?
- A trench is 3 ft wide, 6 ft deep, and 40 ft long. How many cubic yards of spoil are generated (27 cubic feet per cubic yard), a figure needed to plan the 2 ft edge setback and haul-off?
- A plumber must enter a sanitary sewer manhole to make a connection. This is a permit-required confined space. What atmospheric hazard is the leading concern, and what is required before entry?
- Before entry, a manhole 4 ft in diameter and 12 ft deep must be purged with 5 air changes. Using volume = 0.785 x diameter^2 x depth (about 151 ft^3), what total air volume must be moved to complete the purge?
- A plumber sets an extension ladder to reach a roof vent terminal. Using the 4-to-1 rule, how far should the base be from the wall if the ladder contacts the wall 16 ft up?
- Backflow prevention is a public-health safety requirement. What health event does a properly working backflow assembly prevent?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với Master Plumber Licensing Exam (UPC/IPC-based) · Quy trình kiểm tra