Safety and OSHA Regulations Flashcards

Under OSHA's Lockout/Tagout standard (29 CFR 1910.147), which scenario correctly describes when a 'complex' lockout/tagout procedure is required instead of a 'simple' one?

Answer: When the equipment has more than one energy source that requires more than one lockout device

OSHA 29 CFR 1910.147 distinguishes between simple and complex procedures based on energy sources, not employee count, equipment age, or tool requirements. A complex LOTO procedure is required when equipment has multiple energy sources requiring multiple lockout devices, multiple crews, crafts, or trades, or when there is a particular sequence for locking out.

A maintenance technician is working in a confined space classified as 'permit-required.' The air monitor shows oxygen at 20.3%, LEL at 6%, and H₂S at 9 ppm. Which action is MOST appropriate?

Answer: Continue work — all readings are within acceptable limits

OSHA's permit-required confined space standard (29 CFR 1910.146) defines acceptable atmospheric conditions as: oxygen 19.5%–23.5%, flammable gas below 10% LEL, and toxic substances below their permissible exposure limits. H₂S PEL (ceiling) is 20 ppm under 1910.1000; 9 ppm is below it. LEL at 6% is below the 10% action threshold. All three readings are within safe parameters, so work may continue.

According to OSHA's Hazard Communication Standard (29 CFR 1910.1200), a Safety Data Sheet (SDS) Section 8 lists a chemical's TLV-TWA as 25 ppm and a STEL of 75 ppm. An employee is exposed to 30 ppm for a full 8-hour shift. Which statement is MOST accurate?

Answer: The exposure violates the TWA limit even though it is below the STEL

The TWA (Time-Weighted Average) is the concentration limit averaged over an 8-hour workday. At 30 ppm for 8 hours, the 8-hour TWA is 30 ppm, which exceeds the 25 ppm TWA limit. The STEL (Short-Term Exposure Limit) of 75 ppm applies to exposures of 15 minutes or less and is not violated here. TWA and STEL are independent limits; violating the TWA does not require also exceeding the STEL.

Under OSHA's Electrical Safety standard (29 CFR 1910.333), an unqualified employee must maintain a minimum approach distance from exposed energized parts operating at 480 volts. What is the correct minimum distance?

Answer: Any distance that prevents accidental contact (no specific numeric limit for unqualified workers)

OSHA 29 CFR 1910.333(c)(3)(i) states that unqualified persons shall maintain a distance from exposed energized parts 'sufficient to prevent accidental contact.' There is no single fixed numeric distance for unqualified workers in the general industry standard — instead, they must simply stay far enough away that contact is impossible. The specific numerical approach boundaries (e.g., 3 ft, 10 ft) come from NFPA 70E flash protection boundary tables and apply to qualified workers with PPE.

OSHA's Process Safety Management (PSM) standard (29 CFR 1910.119) requires a Process Hazard Analysis (PHA) to be revalidated on what schedule?

Answer: At least every 5 years after the initial PHA

Under 29 CFR 1910.119(e)(6), the PHA must be updated and revalidated by a team with expertise in the process at least every five years after the completion of the initial PHA. This is separate from and in addition to Management of Change (MOC) requirements, which trigger reviews for specific modifications. Annual revalidation is not required under OSHA PSM.

A worker is injured on the job and seeks first aid treatment only — no medical treatment beyond first aid is needed, and the worker returns to full duty the same day. Under OSHA's Recordkeeping Rule (29 CFR 1904), how must the employer handle this incident?

Answer: The incident is NOT recordable and does not need to be entered on the OSHA 300 Log

Under 29 CFR 1904.7, cases that involve only first aid treatment are explicitly exempt from OSHA recordkeeping requirements. 'First aid' is defined by a specific list in the standard (e.g., nonprescription medication at nonprescription strength, cleaning/bandaging wounds, use of nonrigid means of support). If no medical treatment beyond first aid was required and the worker returned to full duty, the incident is not recordable on the OSHA 300 Log. Needlestick injuries have separate recording rules but still require medical treatment to trigger recordability.