OSHA Severity Rate Calculator
This represents the number of lost days per 100 full-time employees.
What is the OSHA Severity Rate?
The OSHA Severity Rate is a safety metric used to quantify the seriousness of workplace injuries and illnesses. While the incidence rate (Frequency Rate) tells you how often accidents happen, the Severity Rate tells you how severe those accidents are by measuring the amount of lost work time they cause.
This calculation calculates the number of lost workdays experienced per 100 full-time equivalent employees (FTEs). A higher severity rate indicates that although accidents might not be frequent, the ones that do occur result in significant time away from work, implying more serious injuries.
The Calculation Formula
The standard formula used for calculating the Severity Rate is based on the OSHA standard benchmark of 200,000 hours (which represents 100 employees working 40 hours per week for 50 weeks a year).
Where:
- Total Lost Work Days: The cumulative number of days employees were away from work due to work-related injuries or illnesses during the reporting period.
- Total Employee Hours Worked: The sum of all actual hours worked by all employees during the same period.
- 200,000: The normalization constant to standardize the rate per 100 full-time employees.
Example Calculation
Let's look at a practical example for a manufacturing plant:
- The company experienced 3 incidents resulting in a total of 45 lost work days.
- The company has 250 employees who worked a total of 500,000 hours during the year.
Plugging these numbers into the calculator:
Calculation: (45 × 200,000) / 500,000 = 9,000,000 / 500,000 = 18.0
This means the facility lost 18 days of productivity for every 100 full-time employees due to injury.
Why is Severity Rate Important?
Tracking the Severity Rate is crucial for EHS (Environment, Health, and Safety) managers for several reasons:
- Depth of Analysis: It provides context to the frequency rate. A company might have very few accidents (low frequency) but if every accident results in months of recovery, there is a critical safety hazard that needs addressing.
- Cost Indicator: Lost days equate to lost productivity and higher workers' compensation costs. A high severity rate is a leading indicator of financial risk.
- Performance Benchmarking: It allows companies to compare their safety performance year-over-year or against industry averages, regardless of changes in workforce size.
How to Lower Your Severity Rate
Improving your severity rate requires a focus on preventing serious injuries, not just minor first-aid incidents. Strategies include:
- Conducting thorough Job Hazard Analyses (JHAs) for high-risk tasks.
- Implementing robust Return-to-Work programs to help employees safely return to light duty sooner.
- Investing in engineering controls to remove hazards that cause debilitating injuries (e.g., fall protection, machine guarding).