HSE Occupational Health and Industrial Hygiene 4 — Questions and Answers
Question 1: A workplace ergonomic assessment reveals that workers must repeatedly lift 40-lb boxes from floor level to shoulder height. Which intervention most directly addresses the root cause?
- Installing a height-adjustable lift table to eliminate the floor-to-shoulder lift (Correct answer)
- Requiring workers to take 10-minute breaks every hour
- Providing back belts to all workers
- Training workers on proper lifting technique only
Correct answer: Installing a height-adjustable lift table to eliminate the floor-to-shoulder lift
An engineering control that eliminates the extreme range of motion directly removes the source of the musculoskeletal hazard, which is more effective than administrative or PPE solutions.
Question 2: Under OSHA's respiratory protection standard (29 CFR 1910.134), before a tight-fitting respirator is issued, an employee must complete which mandatory step?
- Fit testing (Correct answer)
- Pulmonary function testing
- Blood pressure screening
- Industrial hygiene air monitoring
Correct answer: Fit testing
OSHA requires quantitative or qualitative fit testing to verify an adequate seal between the facepiece and the wearer's face before use in a hazardous atmosphere.
Question 3: Which radiation type has the least penetrating power and can be stopped by a sheet of paper or dead skin cells?
- Alpha particles (Correct answer)
- Beta particles
- Gamma rays
- X-rays
Correct answer: Alpha particles
Alpha particles are large and positively charged, losing energy quickly; a sheet of paper or the outer dead layer of skin is sufficient shielding.
Question 4: An occupational health nurse notices a cluster of carpal tunnel syndrome cases in the packing department. What is the most appropriate first step?
- Conduct a systematic ergonomic workstation assessment of the affected department (Correct answer)
- Refer all affected employees to orthopedic surgery immediately
- Issue wrist splints to all packing employees
- Close the department pending investigation
Correct answer: Conduct a systematic ergonomic workstation assessment of the affected department
Identifying the common risk factors through an ergonomic assessment allows targeted engineering or work-practice controls to be applied at the source.
Question 5: What is the correct OSHA confined space classification for a space large enough to enter but not designed for continuous occupancy and that has a limited means of entry or exit?
- Permit-required confined space
- Non-permit confined space (Correct answer)
- Restricted entry space
- Controlled access space
Correct answer: Non-permit confined space
A space meeting the physical definition (large enough to enter, limited entry/exit, not for continuous occupancy) without any serious hazard is classified as a non-permit confined space.
Question 6: Which industrial hygiene sampling strategy involves placing monitors in the breathing zone of individual workers throughout a full work shift?
- Personal sampling (Correct answer)
- Area sampling
- Grab sampling
- Perimeter sampling
Correct answer: Personal sampling
Personal sampling places collection media within 12 inches of the worker's nose and mouth to measure the concentration the individual actually inhales.
Question 7: What measure is used to express the lethal dose of a toxic substance required to kill 50% of a test animal population in a study?
- LD50 (Correct answer)
- LC50
- NOAEL
- LOAEL
Correct answer: LD50
LD50 (lethal dose, 50%) is the single oral or dermal dose that kills half the animal test population and is used to compare acute toxicity between substances.
HSE Occupational Health and Industrial Hygiene 4
A workplace ergonomic assessment reveals that workers must repeatedly lift 40-lb boxes from floor level to shoulder height.
Which intervention most directly addresses the root cause?