If you work in safety, you've almost certainly run into the TRIR — the Total Recordable Incident Rate. It's the most widely used metric for measuring workplace safety performance, and it shows up everywhere: contractor prequalification forms, insurance renewals, OSHA inspection targeting, and bid evaluations. Understanding how to calculate it, what it means, and how your number stacks up against industry averages is core knowledge for any safety professional.
TRIR measures the number of work-related injuries and illnesses per 100 full-time equivalent workers over a given period — typically a calendar year. The "recordable" part refers to incidents that meet what is OSHA's recordkeeping standard under 29 CFR 1904: injuries or illnesses that go beyond simple first aid. A cut that needs a bandage? Not recordable. A cut that needs stitches? Recordable.
The metric is derived directly from your OSHA 300 log. If your company isn't required to keep a 300 log, you'd typically track the same data internally. Either way, the math is the same — and it's simpler than it looks. The OSHA Act established the framework that makes standardized safety tracking possible across industries, requiring most employers with 11 or more employees to maintain injury and illness records.
This guide walks you through the osha trir formula, a worked example, what the numbers actually mean, and how TRIR compares to related metrics like LTIR and DART. Whether you're running an osha trir calculator manually or in a spreadsheet, the underlying formula is always the same. It doesn't change based on company size, industry, or geography — that's what makes it so useful as a universal benchmark.
One thing worth noting up front: TRIR is a lagging indicator. It tells you how many incidents already happened — it doesn't predict future risk. That's why safety professionals use it alongside leading indicators like near-miss reporting, safety observation rates, and training completion. But as a lagging indicator, TRIR is the most widely recognized and acted upon. Clients, insurers, and regulators all use it as a quick proxy for how seriously an organization takes safety. Get comfortable with this number, because it'll follow your company everywhere.
TRIR also feeds directly into two other important rates you'll encounter regularly in safety management: the DART rate and the LTIR (Lost Time Incident Rate). All three use the same 200,000-hour normalization baseline — they just count different subsets of your incident log. We'll break down all three in detail later in this guide, including worked formula examples for each.
Formula: TRIR = (Number of Recordable Incidents × 200,000) ÷ Total Hours Worked
200,000 = 100 employees × 50 weeks × 40 hours/week — the standardized baseline
Result: recordable incidents per 100 full-time workers per year
Source data: OSHA 300 log columns H + I + J (days away + restricted/transferred + other recordable)
Benchmarks: Below 3.0 = acceptable | Below 1.0 = excellent | 0.0 = zero-incident year
The trir formula osha uses looks simple, but let's break it down piece by piece so there's no ambiguity when you're running the numbers.
That 200,000 figure isn't arbitrary — it's the anchor of the whole formula. It represents a baseline of 100 employees each working a full year at 40 hours per week for 50 weeks: 100 × 50 × 40 = 200,000. By multiplying your incident count by this constant before dividing by actual hours worked, you normalize the result to a "per 100 workers" scale.
That means a company with 20 employees and one with 20,000 can compare rates directly — you're always measuring against the same hypothetical 100-worker workforce. This normalization is what makes TRIR useful as an industry benchmark. Without it, a small contractor with 3 incidents would look safer than a large corporation with 50 incidents, even if the small contractor's workers are getting hurt at five times the rate.
Say your company has 500 employees. Over the past year, they collectively worked 1,000,000 hours. Your OSHA 300 log shows 10 recordable incidents. Here's how to calculate trir from osha 300 data:
That company's TRIR is 2.0 — roughly 2 recordable incidents for every 100 workers over the year.
Smaller company — 50 employees, 95,000 hours worked, 3 recordable incidents:
TRIR = (3 × 200,000) ÷ 95,000 = 600,000 ÷ 95,000 ≈ 6.3
Same formula, very different result. A small company with just a few incidents can end up with a high TRIR because of relatively low total hours worked. One severe injury in a 10-person shop can push your rate into double digits — this is why you can't compare small-company TRIRs to large-company TRIRs without context.
When you're doing trir calculation osha-style from actual records, the OSHA 300 log is your source of truth. Pull columns H (days away from work), I (job transfer or restriction), and J (other recordable cases). Sum them — that's your incident count. Never include first-aid-only cases, near-misses, or non-work-related incidents in the trir osha formula.
For total hours worked: pull directly from payroll records. Include overtime, include hours for temporary workers you supervise day-to-day, but exclude paid time off (vacation, sick days, holidays). For salaried workers without time records, OSHA accepts 2,000 hours per year as a standard estimate. Using estimates when actual data is available introduces error — always use real numbers when you have them.
One common mistake: including cases from the prior year that are still active. For annual TRIR, count only cases first recorded during the calendar year in question, even if the worker's days away extend into the following year. Consistency in how you handle these edge cases is what makes your TRIR comparable year over year and defensible in an audit.
Another mistake worth flagging: rounding down incident counts. If your column H shows 3.5 cases because a partial year case is disputed, don't round it to 3. Dispute the classification first, then finalize the count. Rounding creates a false rate and can become a compliance issue if OSHA ever cross-references your 300 log against your 300-A summary submission. The math should reconcile exactly between the two forms.
Any injury or illness requiring treatment beyond first aid — prescription medication, sutures, staples, or physical therapy — must be recorded. Over-the-counter medication at non-prescription strength is first aid and is NOT recordable. The key question: did treatment go beyond what a first-aid kit provides?
If a worker misses one or more days because of a work-related injury or illness, the case is recordable and logged in Column H of the OSHA 300. Even a single missed day triggers recordability. The day of the injury itself does not count — it's the days after.
When a healthcare provider recommends restricted duties or a job transfer due to a work-related condition, that case goes in Column I. Light-duty assignments still count if they're medically required. If the worker returns to their normal job with no restrictions, this category doesn't apply.
Any work-related loss of consciousness — regardless of duration — is automatically recordable. This includes brief fainting episodes caused by occupational exposure, heat stress, or physical trauma on the job. No medical treatment is required; the loss of consciousness alone makes it recordable.
Occupational illnesses diagnosed by a licensed healthcare professional are recordable even if no treatment is administered. Examples include hearing loss above OSHA's action level, occupational asthma, carpal tunnel syndrome diagnosed as work-related, and TB if exposure occurred at work.
OSHA requires recording serious conditions regardless of treatment status. Needlestick injuries involving potentially contaminated sharps are always recordable. New diagnoses of occupational cancer or chronic irreversible diseases linked to workplace exposure must be recorded immediately upon diagnosis.
There's no single universal "good" TRIR — it depends heavily on your industry. The Bureau of Labor Statistics (BLS) publishes annual injury and illness data broken down by NAICS code, and that's the data you need for a meaningful comparison. Comparing your TRIR to the national all-industry average is like comparing a construction company's record to a software firm's — the exposure profiles are completely different. Always benchmark against your own NAICS code.
General rules of thumb: a TRIR below 3.0 is broadly acceptable, below 1.0 is excellent, and 0.0 means a zero-incident year. Recent BLS data shows construction averaging 2.5–3.5, manufacturing around 2.0–3.0, and office-based industries well under 1.0. High-hazard sectors like logging, commercial fishing, and roofing often run above 5.0. A manufacturing plant with a TRIR of 2.0 might be at or below industry average — a financial services firm with the same rate would be a red flag.
It's also worth calculating a three-year rolling average rather than relying on a single year. A one-year spike from a single incident can look dramatic on paper without reflecting a systemic problem, especially for smaller employers. Three years of data gives a more accurate picture of your safety culture and is typically what sophisticated clients and insurance underwriters request when evaluating your company's overall safety performance and trend line over time.
Contractor prequalification: General contractors, facility owners, and government agencies routinely screen vendors by TRIR before awarding work. Hard cutoffs are common — a TRIR above 3.0 or above twice the industry average may disqualify you from bidding regardless of technical qualifications. If you've ever completed an ISNetworld or Avetta prequalification questionnaire, your TRIR is one of the first things evaluated. Companies with poor safety records create liability exposure for clients, so they filter them out early in the selection process.
Insurance underwriting: Workers' comp carriers use TRIR alongside your Experience Modification Rate (EMR) to set premiums. A high TRIR signals a pattern of incidents, which typically means higher premiums and more restrictive policy terms. Conversely, a sustained low TRIR can qualify you for safety credits and better rates. Every fraction of a point you reduce your rate has real dollar value at renewal time.
OSHA inspection targeting: OSHA's Site-Specific Targeting (SST) program identifies high-rate establishments for programmed inspections. If your TRIR is significantly above industry average, you're more likely to receive an inspection even without a triggering complaint or reported injury. Understanding OSHA violations that commonly lead to recordable incidents is one practical way to fix root causes before they end up on your 300 log. Proper OSHA certification for your workforce is another direct lever: trained workers have fewer incidents, and the data consistently backs this up.
Knowing how to calculate trir osha-style is only half the job. Moving the number in the right direction is what actually matters for your business. Here are the practical approaches safety teams use most effectively.
Fix leading indicators first. Near-miss reports, safety observation rates, and hazard identification counts tell you what's about to go wrong if you don't act. Companies that actively track and respond to leading indicators consistently outperform peers on TRIR. If you're only counting incidents after they happen, you're always a step behind the curve.
Analyze root causes, not just incidents. Every recordable has a causal chain. A slip-and-fall isn't just "an accident" — it's the result of a wet floor, no anti-slip mat, poor lighting, or a worker carrying a load that blocked their view. Thorough root cause analysis on every recordable (and near-misses) surfaces patterns that injury counts alone can't show. If six of your ten incidents last year involved the same department or the same task, that's a signal worth acting on systematically.
Invest in consistent training. Workplaces with regular, job-specific safety training have lower injury rates — that's what the data shows year over year. One-time onboarding isn't enough. High-performing safety programs do recurring training, task-specific hazard education, and toolbox talks that keep safety front of mind. Workers who understand the hazards in their specific role make better decisions in the field. This is why investing in your team's safety knowledge has a direct return — it shows up in your TRIR.
Review recordkeeping accuracy annually. First-aid cases logged as recordables inflate your TRIR unnecessarily. Actual recordables excluded from the log create compliance exposure and give you a falsely optimistic number to manage against. Accurate records give you an accurate rate — and a defensible one if OSHA audits. Common errors include counting incidents from the prior year, excluding hours for temp workers you supervise, and misclassifying the severity category. A brief annual audit of your 300 log catches most of these before they compound.
Set annual targets and track progress quarterly. You can't improve what you don't measure consistently. Set a TRIR target at the start of each year based on your prior three-year average and your industry benchmark. Track your running rate quarterly — don't wait until year-end to find out you're off course.
If your Q2 rate is already above your full-year target, you still have time to intervene before the year closes. Some safety teams calculate a projected year-end TRIR each quarter by annualizing the incidents recorded so far, which gives leadership an early warning signal well before the damage is done.
TRIR is the broadest of the three main OSHA safety rates. Here's how they differ and why you need all three for the full picture of your safety performance.
TRIR counts every recordable case: days away from work, restricted duty, job transfer, and other recordables. It's the most comprehensive measure and the one most requested by clients and insurers. A high TRIR means incidents are frequent — but it doesn't tell you how severe they are.
LTIR (Lost Time Incident Rate) counts only cases resulting in actual days away from work (Column H on the 300 log). It's a more severe subset of TRIR. If your TRIR is 3.0 and your LTIR is 0.2, most of your incidents are minor — restricted duty or other recordables that don't knock workers off the job for extended periods.
DART Rate (Days Away, Restricted, or Transferred) sits between TRIR and LTIR. It counts cases resulting in days away from work OR restricted/transferred duty (Columns H + I). OSHA uses the DART rate in its Site-Specific Targeting inspection program alongside TRIR. The relationship between these three numbers tells a severity story: TRIR = 4.0 and LTIR = 3.8 means almost all incidents result in lost time. TRIR = 4.0 and LTIR = 0.4 means most are minor. Both demand action, but different kinds.
Make sure you know how to report to OSHA correctly when severe incidents occur — misclassification of cases skews all three metrics and creates compliance exposure under the OSHA Act recordkeeping requirements. Misreporting is itself a citable violation, separate from the underlying incident.
TRIR = (Number of Recordable Incidents × 200,000) ÷ Total Hours Worked
Recordable incidents = Sum of OSHA 300 log columns H + I + J
200,000 = standardized baseline (100 workers × 50 weeks × 40 hrs/week)
Example: 10 incidents, 1,000,000 hours → TRIR = (10 × 200,000) ÷ 1,000,000 = 2.0
Benchmarks: Below 3.0 = acceptable | Below 1.0 = excellent
LTIR = (Cases with Days Away from Work × 200,000) ÷ Total Hours Worked
Only counts cases from OSHA 300 Column H (days away from work).
Does NOT include restricted duty or job transfer cases.
Example: 4 lost-time cases, 1,000,000 hours → LTIR = (4 × 200,000) ÷ 1,000,000 = 0.8
LTIR is always ≤ TRIR. A large gap between them means most incidents are minor.
DART = (Days Away + Restricted + Transferred Cases × 200,000) ÷ Total Hours Worked
Counts OSHA 300 columns H + I (days away plus restricted/transferred).
More inclusive than LTIR, but excludes other recordable cases included in TRIR.
Example: 7 DART cases, 1,000,000 hours → DART = (7 × 200,000) ÷ 1,000,000 = 1.4
OSHA uses DART rate in its Site-Specific Targeting program for inspection selection.