TRIFR Calculator (Australia)
TRIFR (Per Million Hours)
Based on the Australian standard multiplication factor of 1,000,000.
What is TRIFR?
Total Recordable Injury Frequency Rate (TRIFR) is a key Work Health and Safety (WHS) lagging indicator used extensively in Australia to measure safety performance. Unlike LTIFR (which only counts Lost Time Injuries), TRIFR provides a broader view of safety incidents by including all injuries that required medical attention or restricted work duties, not just those that resulted in time off work.
Monitoring TRIFR allows Australian organizations to identify trends in lower-severity injuries before they escalate into serious incidents.
How to Calculate TRIFR in Australia
The standard formula used in Australia calculates the number of recordable injuries per one million hours worked. This normalization allows companies of different sizes to compare their safety performance accurately.
Total Recordable Injuries (TRI) is the sum of:
- Fatalities: Work-related deaths.
- Lost Time Injuries (LTI): Injuries resulting in the loss of one or more full shifts.
- Medical Treatment Injuries (MTI): Injuries requiring treatment by a medical practitioner (beyond first aid).
- Restricted Work Injuries (RWI): Injuries where the worker can return to work but is unable to perform full duties.
Note: First Aid Injuries are generally NOT included in the TRI calculation.
Calculation Example
Consider a mining company in Western Australia with the following safety data for the financial year:
- 1 Lost Time Injury (LTI)
- 2 Medical Treatment Injuries (MTI)
- 1 Restricted Work Injury (RWI)
- Total Hours Worked: 500,000 hours
Step 1: Calculate Total Recordable Injuries
TRI = 1 + 2 + 1 = 4 injuries
Step 2: Apply the Formula
TRIFR = (4 × 1,000,000) / 500,000
TRIFR = 4,000,000 / 500,000
TRIFR = 8.0
This means there were 8 recordable injuries for every million hours worked.
Why Use 1,000,000 vs 200,000?
In Australia (following Safe Work Australia guidelines) and many parts of Europe, the multiplication factor is 1,000,000. This represents the frequency of injuries per 500 full-time workers working a year. However, in the USA (OSHA standards), the factor is typically 200,000 (representing 100 employees). When benchmarking internationally, ensure you are comparing rates calculated with the same multiplication factor.