What is Severity Rate?
The Severity Rate, often used in occupational health and safety, measures the average time lost per worker due to work-related injuries or illnesses. It provides insight into the impact of incidents on productivity and the overall effectiveness of safety programs. A higher severity rate suggests that incidents, on average, are causing more lost workdays.
The formula for calculating the Severity Rate is:
Severity Rate = (Total Days Lost / Total Workforce Days) * 100
Where:
- Total Days Lost: This is the sum of all days that workers were absent from work due to work-related injuries or illnesses during a specific period. This typically includes days of actual absence, and sometimes also includes days for permanent disability, depending on the reporting standard.
- Total Workforce Days: This represents the total number of days worked by all employees in the workforce during the same period. It is calculated by multiplying the average number of employees by the number of working days in the period. For example, if you have 100 employees working 250 days a year, your total workforce days would be 25,000.
The result is usually expressed as a rate per 100 workforce days. A lower severity rate indicates better safety performance and less disruption from incidents.
function calculateSeverityRate() {
var totalDaysLost = parseFloat(document.getElementById("totalDaysLost").value);
var totalWorkforceDays = parseFloat(document.getElementById("totalWorkforceDays").value);
var resultElement = document.getElementById("severityRateResult");
resultElement.innerHTML = ""; // Clear previous results
if (isNaN(totalDaysLost) || isNaN(totalWorkforceDays)) {
resultElement.innerHTML = "Please enter valid numbers for both fields.";
return;
}
if (totalWorkforceDays <= 0) {
resultElement.innerHTML = "Total Workforce Days must be greater than zero.";
return;
}
if (totalDaysLost < 0) {
resultElement.innerHTML = "Total Days Lost cannot be negative.";
return;
}
var severityRate = (totalDaysLost / totalWorkforceDays) * 100;
resultElement.innerHTML = "Severity Rate:
" + severityRate.toFixed(2) + " days lost per 100 workforce days";
}
.severity-rate-calculator-container {
font-family: sans-serif;
max-width: 800px;
margin: 20px auto;
padding: 20px;
border: 1px solid #ccc;
border-radius: 8px;
background-color: #f9f9f9;
}
.severity-rate-calculator-container h2,
.severity-rate-calculator-container h3 {
text-align: center;
color: #333;
margin-bottom: 20px;
}
.calculator-inputs, .calculator-results, .calculator-explanation {
margin-bottom: 30px;
padding: 15px;
background-color: #fff;
border: 1px solid #eee;
border-radius: 5px;
}
.input-group {
margin-bottom: 15px;
display: flex;
align-items: center;
gap: 10px;
}
.input-group label {
flex: 1;
font-weight: bold;
color: #555;
}
.input-group input[type="number"] {
flex: 2;
padding: 8px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
}
.calculator-inputs button {
display: block;
width: 100%;
padding: 10px 15px;
background-color: #007bff;
color: white;
border: none;
border-radius: 5px;
font-size: 16px;
cursor: pointer;
transition: background-color 0.3s ease;
}
.calculator-inputs button:hover {
background-color: #0056b3;
}
#severityRateResult {
font-size: 1.2em;
font-weight: bold;
color: #28a745;
text-align: center;
}
.calculator-explanation p,
.calculator-explanation ul {
line-height: 1.6;
color: #444;
}
.calculator-explanation strong {
color: #333;
}