Free calculator
Work out your LTIR and severity rate.
Enter your lost-time cases, the days away and the hours worked. You'll get the rates and the math, so you can check it.
Also calledLost time injury rate calculator, LTIFR calculator, Severity rate calculator
Result
LTIR
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Severity rate
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Enter lost-time cases and hours to see LTIR.
Enter days away to see the severity rate.
Definitions of a lost-time case vary by company. Say which one you used when you share the number. OSHA’s days-away cases are the usual starting point.
This does arithmetic on what you type. Nothing leaves your browser. Check the result against your own rules and procedures.
The formulas
- LTIR = (lost-time cases × 200,000) ÷ hours worked by all employees.
- Severity rate = (days away from work × 200,000) ÷ hours worked by all employees.
- The 200,000 base stands for 100 full-time employees working a year, the same base OSHA uses for TRIR and DART.
Read it with care
- There is no single definition of a lost-time case. Some companies count any case where someone missed a shift. Others count the days-away cases on their OSHA 300 log. Some use a different base, such as one million hours. Say which one you used when you share the number.
Run this in the field.
Slice incidents by site, crew or asset type, and open the records behind any number.
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Common questions
- What is the difference between LTIR and TRIR?
- TRIR counts every recordable case. LTIR counts only the cases where someone lost time from work. LTIR is always the same as TRIR or lower for the same year.
- What is a severity rate?
- It's the days away from work per 200,000 hours worked. LTIR tells you how often people lose time. Severity tells you how much time they lose.
- What hours do I count?
- The hours employees actually worked, including overtime. Leave out paid time off. Use payroll hours if you have them.
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