Severity Meaning & Definition | EcoOnline
Health & Safety Glossary



What is Severity?

Severity is simply defined as the degree of hardness of a specific thing. Generally used with negative connotations, severity indicates just how serious or harsh the effects of an incident can be. Severity rate is a commonly used metric by companies to analyze safety standards within a company.

Companies and organizations generally use severity to determine just how critical or serious the effects of an injury or illness can be. It’s calculated by utilizing the average number of lost days due to an accident. This can indicate an organization’s safety performance.


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What is the Importance of Measuring Severity?

Most companies often have specific safety KPIs in place. These are used to track the frequency of incidents in the workplace and provide a clearer picture about the severity of each accident. The number of accidents in a company can be used to determine the effectiveness of safety protocols.

However, the severity rate showcases just how serious each accident is, and how many work days were lost due to each. This is an important metric that goes hand in hand with other safety KPIs and can provide managers with a better understanding of how to improve accident responses to reduce the severity of accidents.

Measuring severity is also important as it highlights the company’s overall safety protocols and helps managers identify areas for improvement. For instance, if there’s only one accident in a company that results in 20-30 lost workdays, the safety managers can look at specific areas to improve their accident response. 


Explaining the Severity Rate Formula

The severity rate formula is generally quite basic and is used to analyze a company’s safety performance. The severity rate formula is as follows: 

(Number of lost workdays x 200,000) / Total number of hours worked by employees.

This is a standardized formula which assumes that 100 full-time employees work 200 hours each year (40 hours for 50 weeks). 

For instance, if a company loses 10 work days due to accidents within a calendar year, and the total number of hours worked was 3,000,000 by all employees, the severity rate would be calculated as follows:

10 lost workdays x 200,000 / 3,000,000 = ~ 1 lost day for each accident. If the industry average is higher than 1, then the company is performing well in terms of safety. 

A higher severity rate would highlight that accidents in the workplace were generally of a more severe nature, resulting in employees taking off from work for extended periods of time. 

Conversely, a low severity rate indicates that any accidents which did occur didn’t actually result in any serious injury or illness. 


The Pros and Cons of Using the Severity Rate

While the severity rate formula is used to showcase the number of lost workdays, there are some fairly obvious weaknesses in the severity rate. 

The primary issue is that the severity rate number is actually an average, which means that the final calculation can be skewed significantly if there’s even one serious incident.

For instance, if a company loses one workday on average, and there’s a major accident at the end of the year that causes an employee to lose several workdays, it could skew the result entirely. 

This is one of the reasons why the severity rate can cause an exaggeration for specific accidents. Simultaneously, if there are multiple accidents but the severity rate is still around one workday or two, it can hide the fact that the company has lax security protocols that causes an increased number of accidents. 

While the severity rate has some glaring issues, it’s generally quite an important safety metric and is used across many industries. For instance, the severity rate highlights specific incidents that cause the most disruption within the company. 

Accidents which result in several weeks off for employees often lead to major disruptions, causing companies to look for replacements, pay workers’ compensation and medical bills, and affect productivity and production in the workplace. 

A higher severity rate often affects worker productivity negatively and is a clear indicator for safety agencies that the company isn’t doing enough to improve its accident response.


Why Should Companies Track and Measure Severity for Different Projects?

Tracking and managing the severity rate is generally much easier than other safety metrics since it only requires a couple of data points; the number of employee work days lost, and the number of hours worked. 

Most companies often include the severity rate in their safety dashboards to track specific functions, KPIs, and other areas of the business. Organizing this information is necessary as it provides clearer insights into the company’s overall safety performance.


Use EcoOnline’s Health & Safety Software to Track Safety Performance

EcoOnline’s Health & Safety software lets you easily track your company’s safety performance. It’s highly modular, and you can use the Event Tracking Software to report, record, and analyze the impact of any safety incidents that occur within your company.