Calculator inputs
Example data table
| Hours | Employees | Recordables | DART | Lost-time | Days lost | TRIR | DART rate | LTIFR | Severity |
|---|---|---|---|---|---|---|---|---|---|
| 208,000 | 100 | 3 | 2 | 1 | 12 | 2.88 | 1.92 | 4.81 | 11.54 |
| 104,000 | 55 | 1 | 1 | 0 | 4 | 1.92 | 1.92 | 0.00 | 7.69 |
| 520,000 | 250 | 10 | 6 | 3 | 45 | 3.85 | 2.31 | 5.77 | 17.31 |
Formula used
- TRIR = (Recordable Incidents × 200,000) ÷ Total Hours Worked.
- DART Rate = (DART Cases × 200,000) ÷ Total Hours Worked.
- LTIFR = (Lost-time Injuries × 1,000,000) ÷ Total Hours Worked.
- Severity Rate = (Days Lost × 200,000) ÷ Total Hours Worked.
- Estimated Injury Cost = Recordable Incidents × Average Cost per Injury.
- Premium Impact (optional) uses TRIR ÷ Benchmark TRIR, scaled by your sensitivity %.
How to use this calculator
- Choose the period label that matches your reporting window.
- Enter total hours worked for that same period.
- Fill incident counts: recordables, DART ca
Budget impact of incident rates
A single recordable case changes TRIR by 200,000 ÷ hours. At 200,000 hours, one case adds 1.00 to TRIR; at 500,000 hours, it adds 0.40. For a 52,000‑hour quarter, one case adds 3.85. Use that sensitivity when forecasting reserves, incentives, and contract pricing. If overtime lifts hours without adding cases, rates fall, but cost per hour can still rise.
Turning cases into comparable metrics
This calculator reports TRIR and DART per 200,000 hours, LTIFR per 1,000,000 hours, and a severity rate based on days lost. If your period has 208,000 hours, three recordables produce TRIR 2.88. Two DART cases produce 1.92. Twelve lost days produce severity 11.54. One lost‑time injury produces LTIFR 4.81. Incidents per 100 employees adds a workforce lens: with 100 employees and three recordables, the value is 3.00.
Cost modeling from inputs
Estimated injury cost equals recordables × average cost per injury. With three recordables and a 4,500 unit cost, total cost is 13,500. Cost per hour is 13,500 ÷ 208,000 = 0.0649. If you plan 260,000 hours next year, the same cost intensity implies 16,874. Budget controls by comparing prevention spend to the modeled savings per avoided case.
Benchmark-driven premium planning
When you enter a benchmark TRIR and base premium, the tool scales a premium delta using the TRIR ratio and your sensitivity percent. Example: TRIR 2.88 versus benchmark 3.00 yields a ratio of 0.96. With 15% sensitivity, premium delta is about −0.58%, lowering a 25,000 premium by roughly 145. If TRIR rises to 4.81, the ratio becomes 1.60 and the delta becomes about +9.62%.
Scenario planning for leadership reviews
Run best, expected, and worst cases by changing incident counts while holding hours constant. At 208,000 hours, moving from three to five recordables increases TRIR from 2.88 to 4.81, and cost rises by two injuries. Pair the chart with the export files to document assumptions, compare periods, and show measurable progress across sites. Use consistent definitions to keep comparisons defensible internally.
FAQs
What is TRIR used for in budgeting?
TRIR normalizes recordable incidents to 200,000 hours, helping you compare sites and periods. Finance teams use it to explain variance, set targets, and translate safety performance into expected cost and premium movement.
Why does the calculator use 200,000 hours?
200,000 represents 100 full‑time employees working 40 hours for 50 weeks. It standardizes incident rates so different headcounts and schedules can be compared consistently.
How should I choose average cost per injury?
Use your historical direct cost per recordable case, or a conservative planning estimate. Keep the figure consistent across scenarios so changes in cost are driven by incident counts and hours, not shifting assumptions.
Can DART be higher than recordables?
Usually no. DART cases are a subset of recordable cases involving days away, restriction, or transfer. If your entry shows DART above recordables, review your counting definitions and period filters.
Is the premium impact result official?
No. It is a planning signal that scales your TRIR against a benchmark using a sensitivity factor. Insurers apply their own underwriting models, modifiers, and credits, so treat the output as directional.
What should I export and share?
Export CSV for spreadsheets and audit trails, and export PDF for emails and approvals. Include the period label, hours, and definitions used so readers can reproduce the rates and compare periods fairly.
- Add days lost to see an optional severity view.
- Enter average cost per injury to estimate financial impact.
- Optionally add a benchmark TRIR and base premium for a planning estimate.
- Press Calculate. Results appear above the form.
- Use Download CSV or Download PDF for sharing.