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9990 · 4.4.3

Health and safety — practice questions

Practice and worked examples for 9990 Health and safety. Short previews only — attempt the full question in MarkScheme against the official scheme.

Worked example 1

A nurse administers the wrong drug dose during a double shift on a understaffed ward. The hospital had cut training budgets and managers discouraged incident reports. Analyse using Reason's model and work-stress theory.

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Swiss cheese — aligned holes: (1) Latent: Understaffing, cut training, culture discouraging reports; (2) Active: Nurse slip under fatigue from double shift (4.4.2 circadian/stress); (3) Defences failed: labelling, checking protocols, staffing ratios.

Human factors: Error is predictable under high load — not purely individual negligence.

Stress (demand-control): High demand, low control → strain, fatigue, impaired attention — occupational health hazard.

Safety culture fix: Blame-free near-miss reporting, restore training, staffing levels, checklist protocols (additional cheese slices).

Evaluation: Swiss cheese is descriptive not prescriptive — does not rank which layer to fix first. Legal duty and psychological safety must align. Link to Maslow — safety needs unmet under chronic hazard.

Worked example 2

A factory recorded 600 near-miss incidents, 30 minor first-aid injuries, and 1 serious lost-time injury over the past year. The average cost of a minor injury is £500, and a serious injury costs the company £50,000. Using Heinrich's Accident Ratio (1-30-600), calculate the potential annual cost saving if a new safety program costing £25,000 is implemented and successfully reduces near-misses by 50%.

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Step 1: Verify the baseline against Heinrich's Ratio. The plant's data (1 serious injury, 30 minor injuries, 600 near-misses) perfectly matches the 1-30-600 ratio. This suggests the model is applicable.

Step 2: Calculate the current annual cost of accidents. This is the sum of the costs of all injuries.

  • Cost of serious injuries = 1 * £50,000 = £50,000
  • Cost of minor injuries = 30 * £500 = £15,000
  • Total Current Annual Cost = £50,000 + £15,000 = £65,000

Step 3: Project the reduction in incidents. The program reduces near-misses by 50%. Assuming the ratio holds, other incidents will also reduce by 50%.

  • Projected serious injuries = 1 * 0.5 = 0.5 per year
  • Projected minor injuries = 30 * 0.5 = 15 per year

Step 4: Calculate the projected new annual cost of accidents.

  • Projected cost of serious injuries = 0.5 * £50,000 = £25,000
  • Projected cost of minor injuries = 15 * £500 = £7,500
  • Total Projected Annual Cost = £25,000 + £7,500 = £32,500

Step 5: Calculate the net cost saving. First, find the gross saving from accident reduction, then subtract the program cost.

  • Gross Saving = Current Cost - Projected Cost = £65,000 - £32,500 = £32,500
  • Net Annual Saving = Gross Saving - Program Cost = £32,500 - £25,000 = £7,500

Final Answer: By investing £25,000 in the safety program, the factory can expect a net saving of £7,500 in the first year, providing a strong financial justification for improving safety culture and practices.

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