Accident Frequency Rate (AFR)
Construction – number of reportable accidents per 100,000 hours worked on site
What is Accident Frequency Rate (AFR)?
Accident frequency rate is the number of reportable accidents for every 100,000 hours worked on site. It shows how often accidents happen relative to the amount of work done.
It is a standard safety measure in construction and engineering, letting companies of different sizes and periods be compared fairly.
How this KPI is measured
- Function
- Human Resources
- Sub-function
- Wellbeing
- Industry
- Construction & Engineering
- Type
- Lagging
- Impact
- Risk
- Unit
- rate/100K hrs
- Measurement frequency
- Monthly
- Formula
- (Reportable accidents × 100,000) / Total site hours worked
How to calculate it
Multiply the number of reportable accidents by 100,000, then divide by total site hours worked.
For example, if there were 6 reportable accidents over 1,200,000 hours, the rate is (6 x 100,000) / 1,200,000 = 0.5.
Use the same definition of reportable throughout, and remember to include subcontractor hours where appropriate.
Where it is used
Monitoring site safety
Track accident trends.
Comparing sites and contractors
Benchmark.
Meeting reporting requirements
Share data with regulators and clients.
How to improve it
Tips and common mistakes
- Do not discourage reporting. Under-reporting hides risk.
- Use with leading measures such as near misses.
- Follow legal reporting requirements.
More Human Resources kpi library
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