Safety, Health, and Environment practice questions

Answer: B) The Safety Data Sheet supplied by the manufacturer

The Safety Data Sheet (SDS) is the 16-section document required by OSHA's Hazard Communication Standard. It covers a chemical's hazards, first-aid measures and safe handling. Labels and the written program serve other purposes.

• AIncorrect. Shipped-container labels must carry a product identifier, signal word, hazard statements, pictograms, precautionary statements and supplier contact information. They are not organized into 16 sections.
• BCorrect. 29 CFR 1910.1200(g) requires SDSs to follow a 16-section format. It includes Section 2 (hazard identification), Section 4 (first-aid measures) and Section 7 (handling and storage).
• CIncorrect. The written program describes how the employer handles labeling, SDSs and training, and it includes a chemical list. It is not a standardized 16-section document about one chemical.
• DIncorrect. The inventory only identifies the hazardous chemicals present. It does not give each chemical's first-aid or handling information.

Answer: A) 10

OSHA Table 1 in 29 CFR 1910.134 gives half-mask air-purifying respirators, including N95 filtering facepieces, an APF of 10. Quarter masks get 5, and full-facepiece air-purifying respirators get 50.

• ACorrect. Table 1 of 1910.134 assigns an APF of 10 to half-mask air-purifying respirators, and this includes filtering facepieces such as N95s. Used within an effective respirator program, the wearer's expected exposure is about one-tenth of the ambient concentration.
• BIncorrect. An APF of 1,000 applies to full-facepiece powered air-purifying respirators and to full-facepiece continuous-flow or pressure-demand supplied-air respirators, not to a half-mask air-purifying respirator.
• CIncorrect. An APF of 50 applies to full-facepiece air-purifying respirators and half-mask PAPRs, among others. A half-mask air-purifying respirator is rated lower.
• DIncorrect. An APF of 5 is assigned to quarter-mask air-purifying respirators. Half masks, including filtering facepieces, are assigned 10.

Answer: C) Oxygen, then flammable gases and vapors, then toxic contaminants

OSHA 1910.146 requires pre-entry atmospheric testing in a fixed order: oxygen first, then combustible (flammable) gases and vapors, then toxic gases and vapors.

• AIncorrect. This reverses the required order. Under 1910.146, oxygen content is tested first.
• BIncorrect. Flammable gases are tested second, after oxygen, not first.
• CCorrect. 1910.146(c)(5)(ii)(C) requires testing for oxygen content, then flammable gases and vapors, then potential toxic air contaminants, 'in that order.' Paragraph (d)(5)(iii) repeats this sequence.
• DIncorrect. Toxic contaminants are tested last, after oxygen and flammable gases and vapors.

Answer: A) 4 ft

• ACorrect. One foot out for every four feet of height.
• BIncorrect. That's far too shallow an angle.
• CIncorrect. Divide the height by 4.
• DIncorrect. Divide the height by 4.

Answer: D) 15 minutes

• AIncorrect. That isn't the guideline.
• BIncorrect. That's far too short.
• CIncorrect. That's too short.
• DCorrect. Then seek medical attention.

Answer: B) Work 20% of the normal duration on day 1, then add 20% each day until reaching the normal schedule

OSHA's Rule of 20 Percent has new workers work 20% of the normal duration on day 1 and add 20% each day after that, along with water, rest and shade. Most reach a full schedule by the end of the first week, though some need up to 14 days.

• AIncorrect. OSHA says new workers should work only 20% of the normal duration on day 1. Jumping to a full schedule on day 2 skips the gradual build-up they need.
• BCorrect. This is OSHA's Rule of 20 Percent: 20% of the normal duration on the first day, increasing by 20% on later days until the worker is on a normal schedule.
• CIncorrect. OSHA calls for a phased schedule for new workers. It also tells employers to use the same protections for workers returning after an absence, so phasing is not only for returning workers.
• DIncorrect. OSHA says to increase work duration by 20% on each later day, not jump to a full schedule. Some workers may need up to 14 days to adapt.

Answer: C) Airborne particles

• AIncorrect. Those need chemical cartridges.
• BIncorrect. Those need supplied air.
• CCorrect. It filters at least 95% of test particles.
• DIncorrect. It filters particles only.

Answer: C) 3 dB

• AIncorrect. That's a tenfold energy increase.
• BIncorrect. That's doubling sound pressure.
• CCorrect. 10 log₁₀ 2 ≈ 3 dB.
• DIncorrect. Use 10 log₁₀ 2.

Answer: D) Energized electrical equipment

• AIncorrect. That's Class D.
• BIncorrect. That's Class A.
• CIncorrect. That's Class B.
• DCorrect. The agent doesn't conduct electricity.

Answer: A) Tripping when it detects current leaking to ground

• ACorrect. It senses imbalance between hot and neutral.
• BIncorrect. That's a surge protector.
• CIncorrect. That's a circuit breaker's main job.
• DIncorrect. It detects ground faults.