Introduction to the Severity Rate Formula

The Severity Rate Calculator is an essential tool for organizations looking to assess the impact of workplace injuries and illnesses. At the heart of this tool is the Severity Rate formula, which calculates the extent of injuries and illnesses within a workplace. This formula is crucial for maintaining a safe work environment and adhering to occupational health standards.

How the Severity Rate is Calculated

To calculate the Severity Rate, the calculator requires two key inputs: the total number of days lost due to injury or illness annually, and the total number of hours worked by all employees in the same period. The formula is:

Severity Rate (SR) = (Number of Lost Workdays × 200,000) / Total Hours Worked by Employees

The multiplier, 200,000, represents the estimated number of hours that 100 employees would work in 50 weeks, providing a standard measure for comparison.


Interpreting the Results

Once the Severity Rate is calculated, it serves as an indicator of the severity of workplace incidents. A higher rate suggests more severe incidents or a greater number of lost days, indicating a need for improved safety measures. Conversely, a lower rate reflects a safer work environment.

Practical Applications and Benefits

Organizations can use the Severity Rate to benchmark their safety performance against industry standards or historical data. Regular monitoring of this rate can help in identifying trends, directing safety initiatives, and reducing workplace incidents. This proactive approach not only enhances employee welfare but can also lead to increased productivity and reduced costs related to workplace injuries.


The Severity Rate Calculator is more than just a mathematical formula; it's a vital tool for ensuring a safe and efficient work environment. By understanding and applying this tool, organizations can significantly improve their safety standards, benefiting both their employees and their operational efficiency.

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