DART Rate Calculator (Days Away, Restricted & Transferred)
Calculate your DART rate — the OSHA standard measure of workplace injuries and illnesses that result in days away from work, restricted duty, or job transfers, per 100 full-time employees.
How to use this tool
- Enter number of dart cases and total hours worked by all employees in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your dart rate and the full breakdown beneath it.
⚠ This tool provides general estimates for education only and is not financial, tax or legal advice. Figures may not reflect your situation — verify with a qualified professional.
Formula
DART Rate = (Number of DART Cases × 200,000) ÷ Total Hours Worked
The constant 200,000 represents 100 full-time employees working 40 hours/week for 50 weeks per year (100 × 40 × 50 = 200,000).
How it works
The DART rate is an OSHA-standard metric that normalizes workplace injury frequency to a baseline of 100 full-time employees. Cases counted are those resulting in days away from work, job transfer, or restricted duty — more severe than simple recordable incidents. A lower DART rate indicates a safer work environment relative to industry benchmarks.
Worked example
Manufacturing Plant Safety Record
- A plant reports 5 DART cases during a year in which employees worked a combined 200,000 hours.
- Apply the formula: DART Rate = (5 × 200,000) ÷ 200,000.
- Numerator: 5 × 200,000 = 1,000,000.
- Divide: 1,000,000 ÷ 200,000 = 5.00.
The DART rate is 5.00, meaning 5 qualifying cases per 100 full-time equivalent employees.
Common mistakes to avoid
- Using calendar days instead of actual hours worked when computing total hours, which underestimates hours and artificially inflates the DART rate.
- Counting all OSHA recordable cases without confirming they also involved days away, restricted duty, or transfer -- not all recordable incidents qualify as DART cases.
- Dividing by 100,000 instead of OSHA's standard 200,000 constant, doubling the calculated rate and making it incomparable to industry benchmarks.
Key terms
- What is a DART case?
- A recordable workplace injury or illness that results in days away from work, restricted work activity, or a job transfer (beyond the day of the incident).
- Why use 200,000 as the constant?
- 200,000 equals 100 full-time employees each working 40 hours per week for 50 weeks — the OSHA standard baseline for rate calculations.
- How does DART differ from TRIR?
- The Total Recordable Incident Rate (TRIR) counts all OSHA recordable cases, while DART counts only the more severe subset that caused days away, restriction, or transfer.
- What is a good DART rate?
- A DART rate below the industry average is desirable. Many industries target below 1.0, though benchmarks vary significantly by sector.
Frequently asked questions
- What is the difference between DART rate and TRIR?
- The Total Recordable Incident Rate (TRIR) includes all OSHA recordable injuries and illnesses. The DART rate counts only cases resulting in days away, restricted duty, or job transfer. DART rate is always less than or equal to TRIR.
- Why does OSHA use the 200,000 constant?
- 200,000 represents the hours worked by 100 full-time employees over 50 weeks (100 x 40 x 50). Multiplying case count by 200,000 and dividing by actual hours normalizes the rate to a per-100-employees basis for fair cross-company comparison.
- What is a good DART rate by industry?
- DART rates vary significantly by industry. Manufacturing averages 1.0-2.0. Construction averages 1.5-2.5. Office and administrative work is typically below 0.5. The Bureau of Labor Statistics publishes annual industry benchmarks.