SafetyCâu 653 / 700
CALCULATION: A free-standing supported scaffold has a minimum base width of 5 feet. Using the common 4:1 height-to-base ratio, at what height must the scaffold first be tied, guyed, or braced to the structure to prevent tipping?
a.10 feet
b.20 feet
c.25 feet
d.40 feet
Giải thích
Correct: the maximum unrestrained height is 4 times the least base dimension, so 4 x 5 ft = 20 ft; above 20 ft the scaffold must be tied or braced to the structure. 10 ft understates it (that would be a 2:1 ratio); 25 ft and 40 ft exceed the 4:1 limit for a 5-ft base and would allow an unstable, tip-prone scaffold.
Luyện miễn phí toàn bộ 700 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Wood platform planks on a scaffold are supported at each end. Where planks are overlapped rather than butted, the overlap must occur over a support and extend at least how far past the centerline of the support?
- Workers need to reach a scaffold platform 9 feet above the base. Which access method is required under Cal/OSHA?
- Who must inspect a scaffold for visible defects, and how often, before it is used?
- On a large jobsite a scaffold tagging system is used at access points. A worker sees a YELLOW tag on a scaffold. What does this MOST likely indicate?
- A supported scaffold is being erected on graded soil. What is the BEST practice for the scaffold's footing?
- CALCULATION: A portable straight ladder rests against a wall where the top touches the wall 16 feet above the base. To meet the 4:1 pitch rule, about how far out from the wall should the ladder's feet be placed?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với California CSLB General Building (B) Trade Examination · Quy trình kiểm tra