DART Rate Calculator (OSHA)
Calculation Results
Your DART Rate is:
Total DART Incidents:
Understanding the DART Rate Calculation Formula
The DART rate (Days Away, Restricted, or Transferred) is a critical safety metric used by the Occupational Safety and Health Administration (OSHA) to measure workplace safety performance. Unlike the Total Recordable Incident Rate (TRIR), which counts all recordable incidents, the DART rate specifically focuses on more severe incidents that result in an employee missing work, being restricted in their duties, or being transferred to another job.
The DART Rate Formula
To calculate your organization's DART rate, you need three specific data points: the number of cases involving days away from work, the number of cases involving job transfer or restriction, and the total number of hours worked by all employees during the reference period (usually one calendar year).
Where:
N = Number of DART incidents (Days Away + Restricted/Transfer cases)
EH = Total employee hours worked
200,000 = Benchmark constant (100 employees × 40 hours × 50 weeks)
Step-by-Step Calculation Guide
- Identify DART Incidents: Sum the number of OSHA recordable injuries/illnesses that resulted in days away from work (Column H on OSHA 300 Log) and those that resulted in job transfer or restriction (Column I on OSHA 300 Log). Do not include "Other Recordable Cases" (Column J).
- Determine Total Hours: Calculate the total number of hours worked by all employees during the specific time period. This should include overtime but exclude vacation, sick leave, and holidays.
- Apply the Constant: Multiply your total number of DART incidents by 200,000. This constant normalizes the data to represent a rate per 100 full-time equivalent employees.
- Divide by Hours: Divide the result by the total hours worked to get your DART rate.
Example Calculation
Let's assume a manufacturing company has the following safety data for the year:
- 3 cases involving days away from work.
- 2 cases involving job restriction or transfer.
- 450,000 total hours worked by all employees.
Step 1: Total DART Incidents = 3 + 2 = 5
Step 2: Multiply by Constant = 5 × 200,000 = 1,000,000
Step 3: Divide by Hours = 1,000,000 / 450,000 = 2.22
The DART rate for this company is 2.22, meaning for every 100 full-time employees, approximately 2.2 experienced an injury severe enough to affect their regular work duties.
Why is DART Rate Important?
The DART rate is often viewed as a more accurate reflection of safety severity than TRIR. A high DART rate indicates that when accidents happen, they tend to be severe enough to impact productivity and employee well-being. Many industries use DART rates to benchmark safety performance, and a lower rate can lead to lower insurance premiums and better eligibility for government contracts.
DART vs. TRIR
While TRIR (Total Recordable Incident Rate) captures the frequency of all OSHA-recordable incidents, DART isolates the incidents that have a direct impact on staffing and operations. It helps safety managers identify if their safety programs are failing to prevent severe injuries, even if minor injuries are being controlled.