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TRIR & DART calculator
Enter recordable incidents, DART cases and hours worked straight from your OSHA 300A summaries. Rates are computed as you type, per year and combined across the three years most prequalification packets ask for.
| Year | Recordables | DART cases | Hours worked | TRIR | DART |
|---|---|---|---|---|---|
| — | — | ||||
| — | — | ||||
| — | — |
Don’t have hours worked handy? Estimate from headcount
Estimated hours
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An estimate only — it assumes every employee worked the full period. Payroll hours are always the defensible number, and a reviewer who asks for hours is asking for those.
How these are calculated
TRIR = (recordable incidents × 200,000) ÷ hours worked. DART uses the same denominator but counts only incidents involving days away, restricted work, or job transfer. The 200,000 is 100 full-time employees × 40 hours × 50 weeks — the normalization that makes a 12-person shop and a 900-person contractor comparable.
Use hours actually worked: include overtime, exclude vacation and holiday. Padding the denominator understates the rate and is the error most likely to be caught on audit.
Nothing you type is uploaded, stored, or sent anywhere — the arithmetic runs entirely in your browser, and there is no signup or email gate on this page.
Collecting these from subcontractors?
Re-keying thirty subs’ figures from thirty differently-formatted 300A summaries is how a wrong number ends up in your file. CoverWarden computes TRIR and DART from the uploaded 300A, checks the EMR letter against the cap you set, and flags where a submitted figure disagrees with the underlying log — and your subs upload through a free link with no account to create.
See how prequalification worksReading the two numbers together
The ratio between them carries more information than either alone. A TRIR of 4.0 with a DART of 3.6 describes a contractor having serious incidents. The same TRIR with a DART of 0.9 describes many minor ones — a different problem, a different fix, and a much easier conversation with a client.
Clients also read the three-year trend rather than a single year. For a small contractor one recordable can swing the rate by more than a full point, which is why a one-year snapshot is close to meaningless and why the combined row above is usually the more defensible figure.
Common mistakes
- Using scheduled hours instead of hours actually worked.
- Counting first-aid-only cases as recordable — the OSHA first-aid list is narrower than intuition.
- Counting days lost rather than cases in the DART column. One injury causing forty days away is one case.
- Including subcontractor hours you do not supervise, or excluding temp workers you direct.
- Mixing a fiscal year into what is a calendar-year metric.
Common questions
What is the TRIR formula?
TRIR = (number of OSHA-recordable incidents × 200,000) ÷ total hours worked in the year. The 200,000 represents 100 full-time employees working 40 hours a week for 50 weeks.
What is the DART formula?
DART = (incidents involving days away, restricted work, or job transfer × 200,000) ÷ total hours worked. It uses the same denominator as TRIR but a narrower numerator.
Do I use scheduled hours or hours actually worked?
Hours actually worked. Include overtime and exclude vacation, holiday and other paid non-work time. Using scheduled hours inflates the denominator and understates the rate.
Can DART be higher than TRIR?
No. DART counts a subset of recordable incidents, so it is always at or below TRIR. A DART above TRIR means one of the two inputs is wrong.
What is a good TRIR?
There is no universal figure. Hiring clients benchmark against the published industry average for your NAICS code and set their own thresholds, so the same rate can pass with one client and fail with another.
Is anything I enter sent to a server?
No. The calculation runs entirely in your browser and nothing is transmitted or stored.