Health, Safety and Environmental Protection: Hazards, Prevention, and Workers' Compensation
Hierarchy of controls
The single most tested concept: controls ranked from most to least effective are elimination, substitution, engineering controls, administrative controls, and PPE. PPE is last because it depends on human behavior and correct use. Questions frequently present a scenario and ask for the best first control - the answer is usually the one that removes the hazard at the source.
Industrial hygiene process
Anticipate, recognize, evaluate, and control. Evaluation means measurement: full-shift time-weighted averages, short-term exposure limits, and ceiling values. Know that OSHA permissible exposure limits are legally enforceable, NIOSH recommended exposure limits are advisory, and ACGIH threshold limit values are consensus guidelines. Confusing these three is a classic distractor.
Program requirements to recognize
Hearing conservation at the 85 dBA action level with annual audiometry and a standard threshold shift defined as a 10 dB average change at 2000, 3000, and 4000 Hz in either ear; respiratory protection requiring medical evaluation before fit testing and annual fit testing; hazard communication with labels, safety data sheets, and training; bloodborne pathogens with exposure control plans; and emergency response planning. Environmental duties include hazardous waste handling, spill reporting, and air and water permits.
Workers' compensation
Compensability generally requires a work-related injury or illness arising out of and in the course of employment. Nurses document objectively, report promptly, and coordinate return-to-work with transitional duty.
Rule of thumb
Ask whether the control protects everyone without relying on individual behavior. Worked example: an 8-hour noise sample averages 92 dBA. That exceeds the 90 dBA permissible exposure limit, so feasible engineering or administrative controls come first, plus enrollment in hearing conservation with baseline and annual audiograms.