Incident Investigation and Emergency Preparedness
This domain tests whether you can investigate to prevent recurrence rather than to assign blame, classify events correctly for OSHA recordkeeping and reporting, and build emergency plans that hold up under a drill or a real event.
Investigation method
Separate immediate causes (unsafe acts and conditions at the moment) from root causes (the management system that allowed them: design, procurement, maintenance backlog, training adequacy, supervision, staffing). Common tools are 5 Whys, fishbone diagrams, fault tree analysis, events and causal factors charting, and barrier analysis using a bow-tie.
Sequence: secure and photograph the scene before anything moves, preserve equipment and records, interview witnesses separately with open-ended questions, build a timeline, analyze causes, then assign corrective actions with owners and dates, verify completion, and share lessons learned.
Recordable versus reportable
An OSHA-recordable case involves death, days away, restricted work or transfer, medical treatment beyond first aid, loss of consciousness, or a significant diagnosis by a physician. Reporting to the agency is separate: a fatality within 8 hours; an in-patient hospitalization, amputation, or loss of an eye within 24 hours.
Emergency preparedness
An emergency action plan under 1910.38 covers reporting procedures, evacuation routes and shelter-in-place, accounting for employees, and rescue duties. Drills test alarm audibility and distinctiveness, assembly and headcount, and interface with the incident command system.
Worked example
A worker lacerates a hand and receives six sutures. Sutures are medical treatment beyond first aid, so the case is recordable on the OSHA log. If the same injury had been closed with a butterfly bandage from the first-aid kit, it would not be recordable. Neither outcome triggers the 24-hour reporting duty, which applies to in-patient hospitalization, amputation, or loss of an eye, not to sutures.
Traps that cost marks
- Writing 'employee was careless' as the root cause and stopping there.
- Cleaning up or restarting the line before the scene is documented.
- Interviewing witnesses together, which contaminates accounts.
- Corrective actions with no owner, date, or verification step.
- Confusing recordability with reportability.
- Plans that never get drilled or updated after a layout change.