How to Calculate Frequency Rate

by

Frequency Rate Calculator (LTIFR & TRIR)

200,000 (OSHA Standard – 100 Employees) 1,000,000 (International Standard)

Calculation Result

What is a Frequency Rate?

In occupational health and safety, the Frequency Rate is a standardized mathematical calculation used to measure the number of injuries or incidents relative to the total number of hours worked by all employees. It allows companies of different sizes to compare their safety performance on an even playing field.

The Frequency Rate Formula

To calculate the frequency rate (such as the Lost Time Injury Frequency Rate or LTIFR), use the following formula:

Frequency Rate = (Number of Incidents × Multiplier) / Total Hours Worked

Understanding the Multipliers

  • 200,000: This represents the number of hours 100 employees would work in a year (100 employees × 40 hours/week × 50 weeks/year). This is the standard used by OSHA in the United States.
  • 1,000,000: This is the international standard often used in Europe and by global manufacturing firms to represent a larger workforce sample.

How to Calculate Frequency Rate: Step-by-Step Example

Let's look at a realistic scenario for a medium-sized manufacturing plant:

  1. Identify Incidents: Suppose the plant had 4 recordable injuries over the last year.
  2. Calculate Total Hours: The company has 80 employees who worked a total of 160,000 hours during that period.
  3. Choose Multiplier: We will use the OSHA standard of 200,000.
  4. Apply Formula: (4 × 200,000) / 160,000 = 800,000 / 160,000 = 5.0.

In this example, the frequency rate is 5.0, meaning for every 100 full-time workers, there were 5 recordable injuries.

Why Tracking Frequency Rates Matters

Measuring safety rates serves several critical business functions:

  • Benchmarking: Compare your company's safety performance against industry averages.
  • Trend Analysis: Identify if safety conditions are improving or declining over time.
  • Insurance Premiums: Lower frequency rates often lead to lower Workers' Compensation insurance costs.
  • Compliance: Many regulatory bodies require the reporting of these metrics annually.
function calculateFrequency() { var incidents = document.getElementById("incidentCount").value; var hours = document.getElementById("totalHours").value; var multiplier = document.getElementById("multiplier").value; var resultArea = document.getElementById("resultArea"); var output = document.getElementById("frequencyOutput"); var interpretation = document.getElementById("interpretation"); // Validation if (incidents === "" || hours === "" || hours <= 0) { alert("Please enter valid numbers. Total hours must be greater than zero."); return; } var incidentVal = parseFloat(incidents); var hourVal = parseFloat(hours); var multiplierVal = parseFloat(multiplier); // Calculation logic var frequencyRate = (incidentVal * multiplierVal) / hourVal; // Formatting the result var finalResult = frequencyRate.toFixed(2); // Displaying the result output.innerHTML = finalResult; var multiplierText = (multiplierVal == 200000) ? "per 100 employees" : "per 1,000,000 hours worked"; interpretation.innerHTML = "This represents " + finalResult + " incidents " + multiplierText + "."; resultArea.style.display = "block"; // Scroll to result resultArea.scrollIntoView({ behavior: 'smooth', block: 'nearest' }); }

Leave a Comment