STSC Ergonomics in Construction — Questions and Answers
Question 1: Which of the following is the MOST common ergonomic risk factor contributing to musculoskeletal disorders (MSDs) in construction workers?
- Chemical exposure from solvent-based coatings
- Repetitive motion, heavy manual lifting, and sustained awkward postures (Correct answer)
- Noise levels exceeding 85 decibels
- UV radiation exposure during outdoor work
Correct answer: Repetitive motion, heavy manual lifting, and sustained awkward postures
Construction workers routinely perform heavy lifting, repetitive tasks, and work in awkward postures — the primary ergonomic risk factors for MSDs such as sprains, strains, and cumulative trauma disorders. MSDs are among the leading causes of lost workdays in the construction industry.
Question 2: A carpenter reports tingling, numbness, and intermittent whitening of the fingers after months of extended use of vibrating power tools. This is MOST consistent with:
- Noise-induced hearing loss
- Hand-Arm Vibration Syndrome (HAVS) (Correct answer)
- Heat-related illness
- Contact dermatitis
Correct answer: Hand-Arm Vibration Syndrome (HAVS)
Prolonged exposure to hand-transmitted vibration from power tools can cause Hand-Arm Vibration Syndrome (HAVS), also called vibration white finger. Symptoms include tingling, numbness, and blanching of the fingers, and the condition can be permanent if exposure is not reduced.
Question 3: Workers are repeatedly lifting 60-pound bags of concrete mix by hand. Which control BEST reduces ergonomic risk, according to the hierarchy of controls?
- Requiring workers to use proper bending-knee technique
- Issuing back-support lifting belts to all crew members
- Using a mechanical lift assist, hand truck, or conveyor (Correct answer)
- Scheduling more frequent rest breaks throughout the shift
Correct answer: Using a mechanical lift assist, hand truck, or conveyor
The hierarchy of controls prioritizes engineering controls (mechanical lifts, conveyors, or dollies) over administrative controls (technique training, breaks) or PPE (lifting belts). Eliminating or reducing the manual lift is always more effective than managing worker behavior.
Question 4: A supervisor observes drywall finishers consistently holding their arms above shoulder height for extended periods. What is the PRIMARY ergonomic concern?
- Increased risk of tripping on overhead equipment
- Elevated risk of shoulder impingement and neck musculoskeletal injury (Correct answer)
- Reduced situational awareness for slip hazards below
- Decreased grip strength on hand tools
Correct answer: Elevated risk of shoulder impingement and neck musculoskeletal injury
Sustained overhead work is a significant ergonomic stressor that increases the risk of shoulder impingement syndrome, rotator cuff injuries, and neck strain. Supervisors should evaluate adjustable scaffolding, work platforms, or extended tools to reduce the need for overhead postures.
Question 5: Under OSHA's General Duty Clause, what must a construction supervisor do when a recognized ergonomic hazard exists on site, even though no specific OSHA ergonomics standard for construction has been issued?
- Document the hazard and include it in the next monthly safety report
- Wait for OSHA to promulgate a specific ergonomics standard before acting
- Take feasible steps to reduce or eliminate the recognized hazard (Correct answer)
- Allow workers to self-select their preferred work methods
Correct answer: Take feasible steps to reduce or eliminate the recognized hazard
Section 5(a)(1) — the General Duty Clause — requires employers to address recognized hazards that are causing or likely to cause death or serious physical harm, even in the absence of a specific OSHA standard. Ergonomic hazards that cause MSDs fall within this obligation.
Question 6: Which administrative control is MOST effective for managing ergonomic risk during sustained repetitive concrete block laying?
- Issuing knee pads to all workers on the task
- Posting an ergonomics warning sign at the work area
- Rotating workers between tasks with different physical demands (Correct answer)
- Conducting a daily toolbox talk about proper lifting posture
Correct answer: Rotating workers between tasks with different physical demands
Job rotation between tasks that use different muscle groups reduces the cumulative exposure time for any single body part, lowering the risk of repetitive strain and cumulative trauma disorders. Toolbox talks and PPE increase awareness or protect against contact hazards but do not reduce ergonomic exposure.
STSC Ergonomics in Construction
Which of the following is the MOST common ergonomic risk factor contributing to musculoskeletal disorders (MSDs) in construction workers?