Calculate Days Away, Restricted, or Transferred (DART) Rate
Include all full-time, part-time, and temporary staff hours.
Calculation Results
Your DART Rate: 0.00
Understanding the OSHA DART Rate
The DART Rate is a critical safety metric used by the Occupational Safety and Health Administration (OSHA) to track how many workplace injuries or illnesses resulted in employees spending time away from work, restricted work activities, or job transfers.
Unlike the Total Recordable Incident Rate (TRIR), which counts every recordable injury, the DART rate focuses specifically on more severe incidents that impacted the employee's ability to perform their normal duties.
The DART Rate Formula
(Total DART Cases × 200,000) / Total Hours Worked
Where:
Total DART Cases: The sum of cases involving days away from work plus cases involving job transfer or restriction.
200,000: This represents the equivalent of 100 employees working 40 hours per week, 50 weeks per year. It standardizes the rate so companies of different sizes can be compared fairly.
Total Hours Worked: The actual total number of hours worked by all employees during the period (excluding vacations and sick leave).
Step-by-Step Example
Suppose your manufacturing plant has the following data for the last calendar year:
Days Away Cases: 2
Job Transfer/Restriction Cases: 3
Total Hours Worked: 450,000
Calculation:
Add the cases: 2 + 3 = 5 total DART incidents.
Multiply by 200,000: 5 × 200,000 = 1,000,000.
Divide by hours: 1,000,000 / 450,000 = 2.22.
The DART rate for this facility is 2.22, meaning for every 100 full-time employees, approximately 2.22 suffered an injury resulting in lost or restricted time.
Why the DART Rate Matters
OSHA uses DART rates to identify high-risk industries and workplaces. A high DART rate relative to your industry average can lead to:
Targeted Inspections: OSHA may prioritize your facility for programmed inspections.
Increased Insurance Premiums: Workers' compensation carriers use safety data to determine rates.
Business Reputation: Many clients and general contractors require DART and TRIR data during the bidding process.
function calculateDartRate() {
var lostDayCases = document.getElementById('lostDayCases').value;
var restrictedCases = document.getElementById('restrictedCases').value;
var totalHours = document.getElementById('totalHoursWorked').value;
var resultArea = document.getElementById('resultArea');
var errorArea = document.getElementById('errorArea');
var dartResult = document.getElementById('dartResult');
var interpretationText = document.getElementById('interpretationText');
// Reset displays
resultArea.style.display = 'none';
errorArea.style.display = 'none';
// Convert to numbers and handle empty inputs as 0 for cases
var ldc = parseFloat(lostDayCases) || 0;
var rc = parseFloat(restrictedCases) || 0;
var th = parseFloat(totalHours);
// Validation
if (isNaN(th) || th <= 0) {
errorArea.innerHTML = 'Error: Please enter a valid number for Total Hours Worked (must be greater than zero).';
errorArea.style.display = 'block';
return;
}
if (ldc < 0 || rc < 0) {
errorArea.innerHTML = 'Error: Incident cases cannot be negative.';
errorArea.style.display = 'block';
return;
}
// DART Calculation
var totalDartCases = ldc + rc;
var rate = (totalDartCases * 200000) / th;
// Round to 2 decimal places
var finalRate = rate.toFixed(2);
// Display Result
dartResult.innerHTML = finalRate;
var msg = "";
if (finalRate == 0) {
msg = "Perfect score! A zero DART rate indicates an excellent safety record for this period.";
} else if (finalRate < 1.0) {
msg = "This is generally considered a low DART rate, indicating strong safety protocols.";
} else if (finalRate < 3.0) {
msg = "This is a moderate DART rate. Check your industry North American Industry Classification System (NAICS) average for comparison.";
} else {
msg = "This DART rate is relatively high. It is recommended to review safety procedures and incident root causes.";
}
interpretationText.innerHTML = msg;
resultArea.style.display = 'block';
// Smooth scroll to result
resultArea.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}