Lost Time Injury Severity Rate Calculator

Severity Rate Formula:

\[ \text{Severity Rate} = \frac{\text{Number of Lost Workdays} \times 200000}{\text{Total Hours Worked}} \]

Severity Rate:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Lost Time Injury Severity Rate?

The Lost Time Injury Severity Rate is a safety metric that measures the severity of workplace injuries by calculating the number of lost workdays per 200,000 hours worked. It helps organizations assess the impact of workplace injuries on productivity and employee wellbeing.

2. How Does the Calculator Work?

The calculator uses the Severity Rate formula:

\[ \text{Severity Rate} = \frac{\text{Number of Lost Workdays} \times 200000}{\text{Total Hours Worked}} \]

Where:

Number of Lost Workdays — Total days away from work due to workplace injuries
Total Hours Worked — Sum of all hours worked by all employees during the period
200,000 — Base for 100 full-time workers (50 weeks × 40 hours × 100 workers)

Explanation: The formula standardizes the severity measurement across organizations of different sizes by using the 200,000 hour baseline.

3. Importance of Severity Rate Calculation

Details: Tracking severity rate helps organizations identify high-risk activities, evaluate safety program effectiveness, prioritize safety improvements, and benchmark against industry standards. A lower severity rate indicates better injury management and workplace safety.

4. Using the Calculator

Tips: Enter the total number of lost workdays (must be ≥ 0) and total hours worked (must be > 0). The calculator will compute the severity rate per 200,000 hours worked.

5. Frequently Asked Questions (FAQ)

Q1: What constitutes a "lost workday"?
A: A lost workday is any day an employee is unable to work due to a work-related injury or illness, excluding the day of injury and any days the employee would not have worked anyway.

Q2: Why use 200,000 hours as the baseline?
A: 200,000 hours represents 100 employees working 40 hours per week for 50 weeks per year, providing a standard benchmark for comparison across organizations.

Q3: How does severity rate differ from frequency rate?
A: Frequency rate measures how often injuries occur, while severity rate measures how serious they are in terms of lost work time.

Q4: What is considered a good severity rate?
A: This varies by industry, but generally lower rates are better. Compare against industry benchmarks and track trends over time within your organization.

Q5: Should all injuries be included in the calculation?
A: Only recordable injuries that result in days away from work should be included, following OSHA recordkeeping guidelines.