Lost Time Injury Severity Rate (LTISR) Calculator

What is Lost Time Injury Severity Rate (LTISR)?

Lost Time Injury Severity Rate (LTISR) is a key workplace safety metric that measures the severity of workplace injuries. It helps organizations understand how serious the injuries are by calculating the number of workdays lost due to reportable incidents per 1 million man-hours worked.

The formula to calculate LTISR is:

LTISR = (Mandays Lost × 1,000,000) ÷ Manhours Worked

A higher LTISR indicates more severe injuries, impacting both employee well-being and organizational productivity. Maintaining a low severity rate is crucial for a strong safety culture and regulatory compliance.

It is important to note that LTISR should be calculated only for lost time injuries that are reportable to statutory authorities. For minor injuries or internal assessments, other indicators like Severity Level (SL) may be more appropriate.

How to Calculate Lost Time Injury Severity Rate?

To accurately calculate LTISR, you need:

  • Mandays Lost: Total man-days lost due to injuries (including scheduled equivalents for fatalities and permanent disabilities).
  • Manhours Worked: Total number of hours worked by all employees during the period.

Example:
If your site had 300 mandays lost over 500,000 manhours worked:

LTISR = (300 × 1,000,000) ÷ 500,000 = 600.00

This means 600 man-days were lost per million hours worked, indicating significant injury severity that requires corrective measures.

LTISR Calculator – Quick & Easy

Use the free LTISR Calculator below to quickly find your organization's Lost Time Injury Severity Rate:

Result:

Your result will appear here

Why Tracking LTISR is Important?

  • Regulatory Compliance: Helps meet OSHA, ISO 45001, and Factories Act requirements.
  • Improved Workplace Safety: Identify critical safety issues and improve preventive programs.
  • Management Reporting: Essential KPI for safety reviews, audits, and external reporting.
  • Benchmarking: Compare safety performance internally and with industry standards.

How to Reduce Lost Time Injury Severity Rate?

  • Conduct regular hazard assessments and site inspections.
  • Implement effective safety training programs for all employees.
  • Establish a strong incident reporting and investigation process.
  • Follow a robust Corrective and Preventive Actions (CAPA) system.
  • Promote the use of Personal Protective Equipment (PPE).
  • Strengthen the Emergency Response Plan (ERP) at each site.

By proactively managing workplace safety risks, organizations can significantly reduce workplace injuries and operational disruptions.

Conclusion

Monitoring your organization's Lost Time Injury Severity Rate (LTISR) is essential for building a safer workplace. Tracking LTISR helps improve regulatory compliance, strengthen safety programs, and reduce overall incident costs.

Use our free LTISR calculator today to make your safety reporting easier and more effective!

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Lost Time Injury Severity Rate Calculator