OSHA Scaffold Safety Quiz — 29 CFR 1926.450-454 Practice Questions — Page 1 of 4
Free OSHA 30-Hour Construction scaffold safety practice test with 40 realistic scenarios. Covers supported scaffolds, suspended scaffolds, aerial lifts, platform construction, guardrails, and competent person inspection with 29 CFR 1926 Subpart L references.
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Q1/ 40
A mason is working from a tubular welded frame scaffold 3 tiers high, approximately 18 feet above grade. The scaffold has no guardrails on the inner face because bricks are being stacked on the platform and the mason claims guardrails would interfere with the work. Is this compliant?
✅ Correct Answer: C
1926.451(g)(1)(vii): for all scaffolds not otherwise specified, each employee more than 10 feet above a lower level must be protected by guardrails or personal fall arrest systems. The masonry scaffold exception that once allowed omission of guardrails on the working face was eliminated — 1926.451(g)(1)(vi) requires guardrails on all open sides. If the workface side truly cannot have guardrails, the employer must implement a PFAS for each affected worker.
Q2/ 40
A scaffold erector is building a supported scaffold. The base plates are set directly on asphalt pavement. The scaffold will reach 40 feet in height. What does 29 CFR 1926.451(c)(2) require for the foundation?
✅ Correct Answer: B
1926.451(c)(2): supported scaffold poles, legs, posts, frames, and uprights shall bear on base plates and mud sills or other adequate firm foundation. The footing must be capable of supporting the loaded scaffold without settling. At 40 feet, vertical and lateral loads are substantial. Additionally, 1926.451(c)(1) requires scaffolds be tied (guys, ties, braces) to the structure at intervals per 1926.451(c)(1)(i) — vertical tie spacing must not exceed 26 feet for scaffold widths under 3 feet. The asphalt alone may concentrate loads and crack.
Q3/ 40
During disassembly of a suspended scaffold at a high-rise window washing project, a worker discovers the wire rope has a broken strand with 4 of its 19 wires broken over a 12-inch section. The worker's supervisor says to finish the job and replace the rope afterward. What should happen?
✅ Correct Answer: C
1926.451(d)(10)(iv): wire ropes must be removed from service when there are 6 randomly distributed broken wires in one rope lay, or 3 broken wires in one strand in one rope lay. 4 broken wires in ONE strand exceeds the 3-wire threshold — immediate removal is required. Splicing suspension ropes (B) is prohibited under 1926.451(d)(10)(vi). The supervisor's instruction would be a willful violation if enforced.
Q4/ 40
A medium-duty scaffold (50 psf rated) is being loaded with masonry blocks. The foreman calculates the total weight of blocks plus workers as 52 psf. The scaffold manufacturer's rated capacity is 50 psf or 1,250 lbs total. The foreman argues it's 'close enough.' What does OSHA require?
✅ Correct Answer: B
1926.451(f)(1): scaffolds and scaffold components shall not be loaded in excess of their maximum intended loads or rated capacities, whichever is less. 1926.451(a)(6): scaffolds shall be designed by a qualified person and shall be constructed and loaded in accordance with that design. 'Close enough' is not a compliance defense — 52 psf exceeds 50 psf, period. For masonry work, a heavy-duty scaffold rated at 75 psf is required per 1926.451(a)(1) when significant material weight is involved.
Q5/ 40
On a two-point suspension scaffold (swing stage), two window installers are working at the 12th floor. The scaffold platform is 32 inches wide. What fall protection is required for each worker?
✅ Correct Answer: B
1926.451(g)(1)(ii): each employee on a single-point or two-point adjustable suspension scaffold shall be protected by BOTH a personal fall arrest system AND a guardrail system. This is a higher standard than supported scaffolds because swing stages present unique risks — hoist failure, platform tilt, and dynamic loading. The PFAS must be attached to an independent vertical lifeline or a structural anchorage, NOT to the scaffold itself unless the scaffold is designed for it.
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Q6/ 40
A competent person inspects a supported scaffold at the start of the shift and finds the cross-bracing is missing a locking pin on the third tier. The competent person tells workers to start using the scaffold while he goes to get a replacement pin. Is this acceptable?
✅ Correct Answer: C
1926.451(f)(3): any scaffold, including accessories such as braces, damaged or weakened from any cause shall be immediately removed from service and shall not be used until repairs are completed. Cross-bracing IS structural — it provides lateral stability. A scaffold with missing locking pins can collapse under load. The competent person's duty is to prevent use, not to allow interim use with warnings.
Q7/ 40
Workers access a scaffold platform by climbing the cross-braces. The scaffold is 25 feet high. The site superintendent says, 'That's how we always do it.' What does OSHA 1926.451(e) require for scaffold access?
✅ Correct Answer: C
1926.451(e)(1): a portable ladder, hook-on ladder, attachable ladder, stairway, or ramp must be provided when access is more than 2 feet above or below a point of access. 1926.451(e)(6)(i) explicitly states: cross-braces are prohibited as a means of access. Additionally, 1926.451(e)(2) requires the bottom rung of access ladders be no more than 24 inches above the starting point. 'How we always do it' is a leading indicator of a serious OSHA violation.
Q8/ 40
A supported scaffold 30 feet high and 5 feet wide (single bay) is erected adjacent to a building but is not yet tied to the structure. Workers notice the scaffold swaying in a 15 mph wind. What does the standard require?
✅ Correct Answer: B
1926.451(c)(1): supported scaffolds with a height-to-base width ratio (including outriggers) of more than 4:1 shall be restrained from tipping by guying, tying, bracing, or equivalent means. At 30 feet high / 5 feet wide = 6:1 ratio — clearly exceeding the 4:1 threshold. The manufacturer's tie pattern must be followed. Counterweights (C) are not a recognized scaffold stabilization method for supported scaffolds.
Q9/ 40
A scaffold is erected directly under an active 7,200-volt overhead power line. The minimum clearance distance from the scaffold to the line is measured at 2.5 feet. Workers are installing siding from the scaffold. Is this compliant?
✅ Correct Answer: C
1926.451(f)(6): scaffolds shall not be erected, used, dismantled, altered, or moved such that they or any conductive material handled on them might come closer to exposed and energized power lines than the distances in 1926.1408 Table A. For lines ≤50 kV (including 7,200V), the minimum clearance is 10 feet. Even insulated lines require clearance — insulation is an additional safeguard, not a substitute for clearance distance. At only 2.5 feet, this is an electrocution waiting to happen.
Q10/ 40
A tube and coupler scaffold is erected by a crew. The qualified person's design called for specific coupler torque values and placement patterns. During inspection, the competent person finds several couplers have been tightened by hand only ('snug tight' but not torqued). What is the correct action?
✅ Correct Answer: C
1926.451(a)(6): scaffolds must be designed by a qualified person and constructed and loaded in accordance with that design. If the design specifies torque values, deviating from them means the scaffold is not constructed per design. 1926.451(f)(3): scaffolds with weakened or altered components must be immediately removed from service. Under-torqued couplers can slip under load, causing progressive collapse. The 'red tag' (flagging for later repair) violates the 'immediately remove from service' requirement.