OSHA Compliance
What Is TRIR? How Employers Calculate the Total Recordable Incident Rate
Employers calculate TRIR from OSHA recordable cases and hours worked, then use the same inputs to see how TCIR and the DART rate differ. The rate is arithmetic, not a recordability decision.
Employers calculate TRIR from OSHA recordable cases and hours worked, then use the same inputs to see how TCIR and the DART rate differ. The rate is arithmetic, not a recordability decision.
TRIR is the total recordable incident rate: OSHA recordable cases times 200,000, divided by the total hours employees worked. The number is only as good as the case count and the hours underneath it.
A TRIR calculation does not decide which injuries are recordable, and it does not grade whether a safety program "worked." It is arithmetic performed after those decisions are made. This guide shows the formula, a worked example, how TRIR differs from TCIR and the DART rate, and the mistakes that make a clean-looking rate wrong.
On This Page
- TRIR Calculation for Employers
- What Goes in the Numerator
- What Goes in the Hours
- TRIR, TCIR, and the DART Rate
- A Rate Is Not a Safety Grade
- Common TRIR Calculation Mistakes
TRIR Calculation for Employers
Use one formula and label the period.
TRIR = (Number of OSHA recordable cases × 200,000) ÷ Total hours worked
The 200,000 hours are the benchmark for 100 full-time employees working 40 hours a week for 50 weeks. It is a scaling factor so a 30-person shop and a 1,000-person contractor can be compared. It is not the hours your site actually worked unless your site happened to work exactly that many.
Worked example, labeled as an illustration only. A contractor has 4 OSHA recordable cases in the calendar year and 400,000 employee hours.
TRIR = (4 × 200,000) ÷ 400,000 = 800,000 ÷ 400,000 = 2.0
Say "2.0 for calendar-year employees" out loud before you put the figure in a bid form. If someone later adds a fifth case, or discovers the hours left out overtime, the rate changes. Recalculate. Do not defend the old number.
| Piece | What to use | Example |
|---|---|---|
| Numerator | OSHA recordable cases in the same period | 4 cases |
| Multiplier | 200,000 hours, the 100-worker benchmark | 200,000 |
| Denominator | All hours worked by the employees in that rate | 400,000 |
| Result | Cases per 100 full-time workers | 2.0 |
What Goes in the Numerator
The numerator is the count of OSHA recordable cases for that employer and that period. It is not the count of clinic visits, near misses, first-aid-only events, or workers' compensation claims. Those lists overlap. They are not the same list.
Which cases belong in the count is the recordability decision. OSHA 1904.7 is the criteria. The OSHA recordable versus reportable guide separates the 300 log from severe-injury reporting clocks. The first aid versus medical treatment guide is where prescription-strength treatment and first aid get sorted. Do not rebuild those tests inside the spreadsheet.
Sending an injured worker to the clinic alone does not make a case recordable. Diagnostic procedures such as X-rays, MRIs, and blood tests are not medical treatment by themselves under OSHA 1904.7. A case can still be recordable when medical treatment, restricted work, job transfer, or days away meets OSHA criteria. Employers remain responsible for final OSHA recordability determinations.
If the case count is wrong, the TRIR calculation is wrong by the same proportion. A site that logs every clinic visit as recordable will publish a high rate that does not match OSHA's test. A site that leaves out restricted-work cases will publish a low rate that a recordkeeping review can unwind.
What Goes in the Hours
The denominator is hours worked by the employees included in that rate, for the same period as the cases. Overtime hours count as hours worked. Paid vacation, sick leave, and holidays generally do not, because they were not hours worked. Confirm the edge cases against OSHA's recordkeeping guidance and the Bureau of Labor Statistics notes on how incidence rates are computed before you lock a bid number.
Practical problems show up at the boundaries.
Temporary and staffing-company workers may sit on the host's log, the staffing firm's log, or both discussions at once. The temporary worker injury guide covers the supervision and recordkeeping split. Do not add their cases and forget their hours, or the reverse.
Multi-employer sites create the same mismatch. The multi-employer worksite guide is the place to sort whose log gets the case. The rate should use the same employer's cases and hours.
Salaried staff who are not paid by the hour still need an hour estimate if they are in the population. Write down the method. "We guessed" is how two people produce two rates from one year of work.
TRIR, TCIR, and the DART Rate
Employers and project owners often use TCIR, total case incident rate, as another name for the same total-recordable calculation as TRIR. If a contract defines TCIR differently, follow the contract and label the figure with that definition. Do not assume the acronyms are different math until you read the form.
The DART rate is narrower. DART means days away, restricted, or transferred. Count only the recordable cases that involved days away from work, restricted work, or job transfer. Then use the same 200,000 and the same hours.
DART = (Days-away, restricted, or transfer cases × 200,000) ÷ Total hours worked
Using the illustration above, if 1 of the 4 recordable cases had restricted work or days away, DART = (1 × 200,000) ÷ 400,000 = 0.5. The other three cases stay in the TRIR calculation and stay out of DART.
Lost-time rate conversations are a third column. The OSHA lost time definition explains days away versus restricted work, and the restricted work versus light duty guide is the test for which of those cases belong in DART. Name the metric on the slide.
A Rate Is Not a Safety Grade
A lower TRIR can mean fewer recordable cases. It can also mean fewer hours in the denominator, a case count that skipped restricted work, or a workforce mix that changed. A higher TRIR can mean a worse year. It can also mean the employer stopped burying restricted-work cases and started applying the 1904.7 test.
Use the rate as a lagging indicator next to leading facts: open restrictions, clinic cycle time, and whether the 300 log matches the medical notes. OSHA recordkeeping support helps employers line the log up with the file. It does not set the rate, and Industrial MD does not determine which cases are recordable.
Workers' comp injury management can shorten the life of a case through clearer restrictions and follow-up. That operational work is not a promise that the annual rate will fall. Claim cost and the OSHA rate move for different reasons. Report them as different numbers.
Common TRIR Calculation Mistakes
| Mistake | What it does to the rate | Fix |
|---|---|---|
| Counting every clinic visit | Inflates the numerator | Apply the 1904.7 test first |
| Leaving out restricted-work cases | Deflates TRIR and DART | Re-read the work-status notes |
| Hours with no overtime | Shrinks the denominator and raises the rate | Pull payroll hours, including OT |
| Cases and hours from different employers | Rate describes nobody | Match the log to the hour file |
| Calling DART a TRIR | Understates total recordables | Label the metric on the form |
| Comparing a partial year to a full year without saying so | Looks like a trend | State the dates next to the number |
Related Industrial MD Services
Employers who want the case file and the log to tell the same story can use OSHA recordkeeping support and Workers' comp injury management. Medical direction helps when a work-status note is too vague to tell restricted work from a full duty release. None of those services calculates a rate for you or decides recordability.
If your next bid form asks for a rate you cannot defend from the log and the hours, talk with Industrial MD about OSHA recordkeeping and injury documentation.
Educational and Employer Responsibility Note
This resource is for general educational and informational purposes. It does not provide legal advice, medical advice, or OSHA compliance counsel. Employers remain responsible for final recordability, employment, and workers' compensation decisions, and for the hours and case counts they report to clients and insurers.
FAQ
What is a TRIR calculation?
A TRIR calculation divides OSHA recordable cases by hours worked and scales the result to 100 full-time workers. Multiply the case count by 200,000, then divide by total hours worked in the same period. The result is a rate, not a recordability decision.
Are TRIR and TCIR different formulas?
Often they are the same total-recordable math under two names. Some contracts define TCIR their own way. Read the form, use that definition, and label the number. Do not invent a second OSHA formula.
What is the DART rate compared with TRIR?
TRIR counts all OSHA recordable cases. DART counts only the recordable cases with days away, restricted work, or job transfer. Both use 200,000 and the same hours. DART is lower than or equal to TRIR for the same period when the inputs match.
Do clinic visits raise the TRIR?
Only if the case is OSHA recordable. A clinic visit alone does not make a case recordable. First-aid-only visits stay out of the numerator. Medical treatment beyond first aid, restricted work, job transfer, or days away can put a case in the count. Employers make that call under 1904.7.
Who should sign off on the hours?
The person who owns the OSHA log and the person who owns payroll hours should agree on the population, the dates, overtime, and any estimated hours for salaried staff. A rate with an undocumented hour file will not survive a client audit or an internal review.