Understanding Lost Time Injury Rate
How we calculate. LTIR = (LTI count × 200,000) ÷ total hours worked. The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.
Real-world scenario: A typical Lost Time Injury Rate case uses lost-time injuries 1 and hours worked 400000. Enter the same figures below to reproduce the worked path.
What is Lost Time Injury Rate?
A severity-focused safety rate that pairs with TRIR. LTIR counts injuries with days away; TRIR includes broader recordables.
- LTI definition per safety policy
- Same hours base as TRIR when comparing
- Result is a rate, not a percent
The Formula
Worked Example
Common Use Cases
- Safety scorecards: severity rate
- Prequalification: LTI history
- Project reviews: TRIR vs LTIR
Pro Tips
- Align LTI criteria with insurer/owner
- Report beside TRIR
- Not a substitute for legal reporting
Limitations: Lost Time Injury Rate results are educational construction planning aids—not engineering, safety, legal, or cost-estimating advice. Confirm definitions with your project controls, safety, and contract documents. For earned-value SPI/CPI see the Professional hub.
FAQ
LTIR vs TRIR?
TRIR counts recordable incidents; LTIR counts lost-time injuries only. Both often use the 200,000-hour scale.
What if hours worked is 0?
LTIR is undefined—enter positive hours worked.
Authoritative References
For construction project controls and safety rate concepts, consult: