Question 1 of 7: Safety Engineering, Accident Theory, and Prevention Approaches

Question 1: Safety Engineering, Accident Theory, and Prevention Approaches (20 marks: 6/7/7)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

(i) Safety Engineering versus Safety Practice

• Safety engineering — applying engineering principles to design workplaces, equipment and processes so hazards are designed out or controlled at source (hazard analysis, risk assessment, guarding, ventilation, fail-safe design). Proactive and technical.
• Safety practice — the day-to-day management/administrative activities that maintain safe operations: training, procedures, inspections, permits, PPE programs, incident reporting, enforcement and safety culture. Operational and behavioural.
• Engineering builds safety in; practice sustains it. Both are essential.

(ii) Multiple-Factor Theory (diagram)

Among incident and accident theories, the single-cause and domino (Heinrich) theories trace an accident along one chain of events; multiple-factor theory instead holds that an incident or accident results from the convergence of several contributing factors (the "4 M's"), and removing or controlling any one may prevent it.

        MAN (human)          MACHINE (equipment)
        - fatigue, error     - poor guarding, defect
              \                    /
               +----> ACCIDENT <--+
              /                    \
      MEDIA (environment)     MANAGEMENT (system)
      - noise, housekeeping   - training, procedures

(iii) Reactive versus Proactive Prevention

(a) Reactive — preventive actions derived from accidents that already happened:

Accident → Investigate → Find cause → Corrective action → Prevent recurrence

(b) Proactive — hazards found and controlled before any accident:

Hazard identification → Risk assessment → Controls → Monitor/audit → Accident avoided

• The reactive approach "learns from blood"; the proactive approach prevents the first injury. A mature program uses proactive as the primary defence and reactive to close remaining gaps.