CHST Concrete, Masonry, and Formwork Safety 3 — Questions and Answers
Question 1: Before an employer places construction loads on a concrete structure, who must determine the structure can support them?
- The concrete supplier
- A qualified person, based on information received (Correct answer)
- The site foreman alone
- The local building inspector
Correct answer: A qualified person, based on information received
1926.701(a) prohibits construction loads unless the employer determines, based on information from a qualified person, that the structure can support them.
Question 2: When must erected shoring be inspected according to 1926.703?
- Immediately before, during, and immediately after concrete placement (Correct answer)
- Once per shift only
- Only after the concrete reaches design strength
- Weekly by a competent person
Correct answer: Immediately before, during, and immediately after concrete placement
Erected shoring must be inspected immediately prior to, during, and immediately after concrete placement.
Question 3: What does OSHA say about adjusting shoring screws after concrete has been placed?
- They may be raised to correct deflection
- They may be adjusted only by the pump operator
- They must not be adjusted to raise formwork after placement (Correct answer)
- They must be tightened every hour during curing
Correct answer: They must not be adjusted to raise formwork after placement
Adjustment screws shall not be adjusted to raise formwork after the concrete is in place, as this can overload or collapse the form.
Question 4: How must formwork removal timing be determined under 1926.703(e)?
- After a fixed 7-day cure in all cases
- When concrete looks dry and hard
- At the discretion of the stripping crew
- When concrete has gained sufficient strength per plans/specifications or appropriate ASTM tests (Correct answer)
Correct answer: When concrete has gained sufficient strength per plans/specifications or appropriate ASTM tests
Forms and shores may not be removed until the concrete has gained sufficient strength, as shown by plans/specifications or ASTM test methods.
Question 5: What must be kept at the jobsite for formwork, including shoring equipment?
- Only the supplier's invoice
- Drawings or plans, including all revisions (Correct answer)
- A photo log of the previous project
- The concrete mix ticket only
Correct answer: Drawings or plans, including all revisions
Drawings or plans, including all revisions, for jack layout, formwork, shoring, working decks, and scaffolds must be available at the jobsite.
Question 6: Eccentric loads on shore heads are permitted only when what condition is met?
- The shoring has been designed for such loading (Correct answer)
- The shores are steel rather than wood
- A spotter is present
- The slab is less than 6 inches thick
Correct answer: The shoring has been designed for such loading
Eccentric loads on shore heads and similar members are prohibited unless the shoring was designed for such loading.
Question 7: When is reshoring required after stripping forms?
- Never, once forms are removed
- Only for precast elements
- When necessary to safely support slabs and beams after stripping or when subjected to superimposed loads (Correct answer)
- Only during winter concreting
Correct answer: When necessary to safely support slabs and beams after stripping or when subjected to superimposed loads
Reshoring must be provided when necessary to safely support slabs and beams after stripping or under superimposed loads.
