To calculate the total recordable incident rate, take the number of OSHA-recordable cases on your 300 log for the calendar year, multiply by 200,000, then divide by the total hours worked by all covered employees that year. The result is an incidence rate: recordable cases per 100 full-time workers. It takes about 20 minutes once your logs are current.
The number itself is simple. Most of the trouble comes from the two inputs. Employers routinely inflate the numerator by counting first-aid events and near misses, or understate the denominator by leaving out part-time, seasonal, temporary and overtime hours.
I have watched safety managers in r/SafetyProfessionals argue for years over whether the multiplier should be 200,000 or 1,000,000, and one consultant tracking rates for small-business clients in a spreadsheet described that particular argument as the thing that “drives me up the freakin’ wall.” Both numbers are legitimate; they belong to different metrics. That confusion, plus a handful of avoidable counting errors, accounts for most of the bad TRIR figures I see published.
Table of Contents
What You Need
The total recordable incident rate, usually shortened to TRIR, is OSHA’s standard frequency measure: how many recordable work-related injuries and illnesses occurred for every 100 full-time equivalent employees in a calendar year. It appears on Form 300A, gets posted in the workplace, and shows up in contractor prequalification reviews and insurance conversations. It is also, by itself, a fairly blunt instrument. Treat it as a starting measure rather than a verdict on your safety program.
Before you touch a spreadsheet, line up five things:
- The OSHA 300 Log. This is the running list of recordable cases. Every case that ends up in the numerator has to appear here first, with the right checkboxes ticked.
- Form 300A, the annual summary. One per establishment, certified by a company executive, and posted between February 1 and April 30 each year.
- Form 301 incident reports. The detail behind each 300 log entry. You need these to settle borderline cases, and our guide on how to fill out an incident report at work covers what a complete one looks like.
- Total hours worked. Actual hours on the clock for every covered employee, including part-time, seasonal, temporary, administrative, clerical, supervisory staff and overtime.
- A defined reporting period. Normally January 1 to December 31.
Also check whether you are a partially exempt employer. Small employers in a partially exempt industry may be able to post the 300A without keeping the full 300 log, but the OSHA recordability criteria in 29 CFR 1904.7 still apply whenever you do log cases, and clients or insurers generally expect a TRIR either way.
Step-by-Step: How to Calculate Total Recordable Incident Rate
Here is the whole method in one line:
TRIR = (Number of recordable cases x 200,000) / Total hours worked
Why 200,000? Because it represents the hours worked in one year by 100 full-time employees: 100 workers x 40 hours a week x 50 working weeks. Multiplying by 200,000 converts any company’s raw numbers into cases per 100 full-time equivalent workers, which is what makes a 12-person shop and a 12,000-person plant comparable.
1. Confirm the Reporting Period
OSHA measures on a calendar year. Everything you count and every hour you add has to come from that same January-to-December window, or your numerator and denominator describe different populations and the resulting rate is fiction.
Quarterly rates are fine for internal trending. Just label them as quarterly so nobody compares them against a calendar-year number later. If you have acquired or divested a site mid-year, decide up front whether to report the site only for the months you owned it, and write that decision down.
2. Count OSHA Recordable Cases
A case is recordable if it is work-related and meets at least one of these conditions under 29 CFR 1904.7: it results in death, days away from work, restricted work or a job transfer, loss of consciousness, medical treatment beyond first aid, or a diagnosis of a significant injury or illness that would likely keep the employee from doing routine work for a year or result in permanent impairment.
Several specific situations count as medical treatment beyond first aid: treatment by a licensed healthcare professional, prescription medication, the employee keeping the injury wrapped or bandaged, any form of surgery, and diagnostic tests such as X-rays or blood work. Needlestick injuries, medical removal protection, tuberculosis exposure and hearing loss that crosses the standard threshold shift all count even without treatment beyond first aid. If a needlestick is involved, our step-by-step on bloodborne pathogen exposure after an incident covers the reporting timeline you also owe.
| Incident | Counts in the numerator? | Why |
|---|---|---|
| Sprained wrist, employee keeps it wrapped and works full duty | No | First aid only, no treatment beyond it |
| Same sprain, seen by a physician and given a prescription | Yes | Medical treatment beyond first aid |
| Slip on a loading dock, no treatment, no lost time | No | No recordable criterion met |
| Back strain needing a doctor’s visit and light duty | Yes | Medical treatment plus restricted work |
| Near miss, nothing damaged or hurt | No | No incident occurred |
| Heat-related illness diagnosed by a clinician | Yes | Diagnosis of a significant illness |
| Back pain reported after a long drive home in a personal vehicle | No | Not work-related |
Count each case once. If someone is restricted for a week and then sent home for a week, that is still a single case with a single start date. When you add them up, use the totals line at the bottom of the 300 log rather than re-tallying entries by hand.
3. Total Employee Hours Worked
The denominator is actual hours worked, not hours scheduled and not payroll totals. Overtime hours count. Hours worked by temporary and contract workers count when you supervise them. Hours for employees who are on the clock but not producing still count, because that is real exposure time.
Do not count hours for people who were never on your payroll: independent contractors you do not supervise, volunteers, or staff at a location you do not control. Those exclusions are frequent sources of disputes when a rate is compared across companies.
If you do not run a timekeeping system, you can still build a defensible denominator. Take the FTE count by month, multiply by roughly 173 hours for a full-time employee, and adjust for overtime and partial-year staff. Document the method you used in a note alongside the calculation so an auditor or client can follow it. A clearly labeled estimate beats a number someone invented in a spreadsheet last spring.
4. Apply the Total Recordable Incident Rate (TRIR) Formula
Example one, a mid-size employer: A 240-person distribution company records 11 cases in 2026 and its employees worked 468,000 hours that year.
TRIR = (11 x 200,000) / 468,000 = 2,200,000 / 468,000 = 4.70
That result means 4.7 recordable cases for every 100 full-time equivalent workers in 2026.
Example two, a small employer: A 14-person specialty contractor has 2 recordable cases and 96,000 hours worked.
TRIR = (2 x 200,000) / 96,000 = 400,000 / 96,000 = 3.33
Two injuries is a small number, but at this size it produces a rate that looks similar to a 500-person company’s rate with ten times the headcount. This is why small-employer rates swing so violently from year to year. Aggregating three years fixes it: 5 cases and 288,000 hours gives (5 x 200,000) / 288,000 = 3.47, and that number means something.
Example three, multiple sites: A company with two plants under one corporate 300A adds cases and hours across establishments first, then applies the formula once.
Plant A: 6 cases, 210,000 hours. Plant B: 3 cases, 140,000 hours. Combined: 9 cases, 350,000 hours.
TRIR = (9 x 200,000) / 350,000 = 1,800,000 / 350,000 = 5.14
Averaging the two plant rates would give 6.67 and 4.29, which overstates the combined result because Plant A carried more hours. When employers operating several sites publish rates, the combined calculation is the one that stays consistent with BLS data, which is also calculated establishment by establishment and then combined.
5. Check and Report the Result
Round to two decimal places and do it the same way every year. A rate of 2.705 and a rate of 2.71 are not meaningfully different, and switching conventions between reports makes trend lines useless.
Compare against your own prior year first, then against Bureau of Labor Statistics data for your industry and establishment size. Label the result as an incidence rate, never a percentage or a probability. A TRIR of 4.7 does not mean 4.7 percent of your workforce was injured; it means 4.7 cases per 100 FTE.
Recent BLS survey years have placed private industry averages in the low-to-mid 2s, with construction and manufacturing well above that and professional services well below. Pull the current figures for your own NAICS code and size category from the BLS occupational injuries and illnesses program rather than quoting a number you saw in an old blog post, because the published rates move each survey year.
Common Mistakes
Most incorrect rates come from one of six errors:
1. Using 1,000,000 instead of 200,000 for TRIR. The million-hour constant belongs to lost-time injury frequency rate and several British-style accident frequency measures, not to TRIR. If you see a number five times larger than its neighbors, check the multiplier first. Here is the mapping that resolves the argument:
| Metric | Numerator | Constant | What it isolates |
|---|---|---|---|
| TRIR (also TRC, TRI, OSHA incident rate) | All recordable cases | 200,000 | Frequency of all recordable events |
| DART | Days away, restricted, or transferred cases | 200,000 | Frequency of cases that affect the job |
| LTIR / LTIFR | Lost-time cases | 1,000,000 in most company programs; some use 200,000 | Frequency of lost-time injuries |
| Severity rate | Days away or restricted | 200,000 | Impact rather than frequency |
Note the trap: many employers calculate LTIFR on the same 200,000 base. The constant is a company convention, not an OSHA requirement, so always ask what basis a comparison figure uses.
2. Counting first-aid cases and near misses. If the only treatment was a bandage, an ice pack or a cleaning from the first-aid kit, the case does not belong in the numerator. Neither does a near miss, an equipment malfunction with no injury, or a claim that has not been evaluated yet.
3. Mixing reporting periods. Twelve months of cases over six months of hours produces a rate twice as high as reality. This is the easiest error to make when someone compiles the 300 log in January but pulls hours from a fiscal-year payroll report.
4. Leaving hours out of the denominator. Excluding overtime, part-time staff, seasonal workers, temps or office staff shrinks the denominator and inflates the rate. It is the single most common reason a company’s TRIR looks worse than the underlying data supports.
5. Comparing across industries without size context. Construction and warehousing have higher reportable rates than finance or software largely because the work involves more exposure hours of physical hazard. Pull the comparison for your NAICS code and your establishment size band, not the private industry average.
6. Reusing last year’s hours. Growing companies are tempted to keep a stable denominator year to year so the rate only moves when incidents change. Every hour worked counts, every year.
To audit an existing spreadsheet, work through four checks: pull the numerator straight from the 300 log total line; confirm the denominator matches the same calendar year; rebuild the hours figure from payroll, adding overtime and including temporary workers; and confirm the constant is 200,000. If any of the four does not reconcile, fix it before the number goes to a client.
Frequently Asked Questions
Why is TRIR calculated using 200,000 hours?
Because 200,000 represents one year of work by 100 full-time employees: 100 workers times 40 hours per week times 50 working weeks. Multiplying by that constant converts your raw count into cases per 100 full-time equivalent workers, which is how OSHA expresses incidence rates and how BLS publishes them. It is a normalization choice, not a safety threshold.
Does first aid count toward the total recordable incident rate?
No. An injury that needs only first aid does not meet any recordability criterion in 29 CFR 1904.7 and stays out of the numerator. Exceptions exist: needlestick injuries involving potentially infectious material, medical removal protection, tuberculosis exposure, and hearing loss that crosses the standard threshold shift count as recordable even without treatment beyond first aid.
What counts as a good TRIR?
It depends on your industry and your size. Recent BLS survey years put private industry averages in the low-to-mid 2s per 100 full-time workers, with construction and manufacturing well above and professional services well below. A meaningful judgment compares your rate to the BLS figure for your NAICS code and establishment size, and to your own trend over three years.
Is LTIFR 1,000,000 or 200,000?
Both exist. TRIR, DART and severity rates use a 200,000-hour base. Lost-time injury frequency rate is calculated on 1,000,000 hours by many companies and on 200,000 by others, because OSHA does not prescribe it. Any LTIFR you read should be accompanied by its base. Converting a 200,000-based LTIFR to a million basis requires multiplying by five.
Where do I find my TRIR rate?
Your own rate comes from your OSHA 300 log: total recordable cases in the summary line, with total hours worked for the same calendar year, run through the formula. Form 300A carries the summary and stays posted from February 1 through April 30. You can also get your establishment’s published rate from the BLS occupational injuries and illnesses tables, searchable by NAICS code and industry.
How should small employers handle TRIR volatility?
Aggregate. Combine cases and hours across three years, then apply the 200,000 constant once to the totals. A single injury at a 12-person business can swing the annual rate by several whole points, which makes year-to-year comparison meaningless. The three-year total smooths that out and is still a valid incidence rate under OSHA rules.
Conclusion: Start With the OSHA Logs
Open the 300 log, read the totals line, and write that number at the top of your sheet. Everything after that is arithmetic: multiply recordable cases by 200,000, divide by total hours worked for the same calendar year, and round to two decimals. If the hours figure is not trustworthy, fix that before publishing anything.
And remember what the number is. TRIR is a lagging frequency measure that treats a splinter removed at a first-aid station the same as a fracture, and it says nothing about the near misses you got lucky on. Track leading indicators alongside it, and check current OSHA recordkeeping requirements and 29 CFR 1904.7 before you rely on your figures.