OSHA Incident Rate Calculator

OSHA incident rate calculator computes TRIR, LTIR, DART, severity rate, and LTIFR from your workplace injury cases and total hours worked. Used by HR teams, OSH professionals, and EHS managers to track workplace safety performance, file OSHA Form 300A, benchmark against BLS industry averages, and report lost-time injury frequency rates. Supports the OSHA standard 200,000-hour base and the international 1,000,000-hour LTIFR convention.

Quick Answer

OSHA incident rate = (Number of cases x 200,000) divided by total hours worked. The 200,000 hours represents 100 full-time employees working a full year, so the result is incidents per 100 FTE workers. Use TRIR for all recordables, LTIR for lost-time cases, DART for restricted-duty cases, and LTIFR (multiplier 1,000,000) for international reporting.

Enter Values

Pick the OSHA or international metric you need to report.

Recordable injuries, lost-time incidents, or DART cases for the period

Total days away from work, restricted, or transferred. Used for the Severity Rate calculation only.

All hours worked by all employees during the reporting period (typically a year)

Result

Enter values above and click Calculate to see your result.

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Formula

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Core Formula
Incident Rate=Number of Cases×200,000Total Hours Worked\text{Incident Rate} = \frac{\text{Number of Cases} \times 200{,}000}{\text{Total Hours Worked}}

How it works: OSHA incident rates normalize injury counts against the size of the workforce. The 200,000 multiplier represents 100 full-time employees working 40 hours per week for 50 weeks (the equivalent of one year of work for 100 people). Dividing by total hours worked then multiplying by 200,000 produces a rate per 100 FTE workers, which is the OSHA reporting standard. International LTIFR uses 1,000,000 hours instead, expressing rates per million hours worked.

Review and Methodology

Updated May 6, 2026

This calculator runs locally in your browser. Inputs are converted into the units required by the formula, and the result is paired with supporting references so you can verify the method before using it for planning or estimates.

Worked Example

A construction company had 4 OSHA-recordable injuries in 2025. The team logged 480,000 total hours worked across the year:
1Step 1: Multiply cases by 200,000 = 4 x 200,000 = 800,000
2Step 2: Divide by total hours worked = 800,000 / 480,000 = 1.67
3Step 3: TRIR = 1.67 incidents per 100 full-time workers per year
4Step 4: Compare to BLS construction industry average (TRIR around 2.5)
Result: 1.67 TRIR is below the construction industry average, indicating a safer-than-typical workplace.

Understanding TRIR, LTIR, DART, and LTIFR for Workplace Safety

OSHA incident rates turn raw injury counts into a number that can be compared across companies and years. The 200,000-hour base is a fixed normalizer, not a real measurement. It represents the labor of 100 full-time workers across one year (100 x 40 x 50). Whatever your headcount, dividing your incident count by your real hours worked then multiplying by 200,000 lets a 50-person site compare directly with a 5,000-person enterprise.

TRIR is the broadest metric. It counts every OSHA-recordable case: any injury that required medical treatment beyond first aid, any case of lost time, any restricted-duty assignment, hearing-loss diagnosis, or fatality. LTIR narrows that to cases where the employee missed at least one full day of work, while DART narrows it to days away, restricted duty, and transfer cases.

Severity Rate uses the same 200,000 multiplier but swaps case count for total lost workdays in the numerator. It is the metric that catches a workplace where there are few injuries but each one is serious. Pair it with TRIR to see frequency and intensity together.

LTIFR is the international cousin of LTIR. Australia, the UK, the EU, and most resource and energy industries report LTIFR per million hours worked. Multiply your LTIR by 5 to convert to LTIFR (because 1,000,000 / 200,000 = 5). World-class operators target LTIFR under 1.0.

The top three drivers of high incident rates are inadequate training, unclear hazard reporting workflows, and gaps between supervisors and frontline crews. Tracking these rates is the first step. Closing the loop with case follow-ups, return-to-work coordination, and predictive analysis is where rates actually come down.

  • TRIR formula: (Recordable Cases x 200,000) / Total Hours Worked. BLS private-industry average is around 2.7; below 1.0 is excellent.
  • LTIR counts only cases with at least one full day away from work. Always lower than TRIR for the same site.
  • DART rate includes Days Away, Restricted duty, or Transferred cases. BLS national average is 1.7.
  • Severity Rate replaces case count with total lost workdays to track injury intensity, not just frequency.
  • LTIFR uses a 1,000,000-hour multiplier (international standard). Multiply LTIR by 5 to convert.

Use this calculator before filing OSHA Form 300A, during contractor prequalification, or as part of monthly EHS dashboards. Pair it with the Cost Per Hire Calculator and Cost of Bad Hire Calculator to estimate the full financial impact of workplace incidents on your team.

You can also calculate changes using our Workplace Injury Cost Calculator, Cost of Bad Hire Calculator, Employee Turnover Cost Calculator, ROI Calculator or Break-Even Calculator.

TRIR and DART Industry Benchmarks (BLS)

U.S. Bureau of Labor Statistics private-industry TRIR and DART averages by sector. Compare your rate against your specific industry rather than the all-industry figure to set realistic safety targets.

IndustryTRIRDARTNotes
All Private Industry (avg)2.71.7National baseline reference
Agriculture, Forestry, Fishing4.62.6High-hazard outdoor and equipment work
Construction2.51.5Falls, struck-by, electrocution top hazards
Manufacturing3.31.6Machine guarding and ergonomics drive rates
Wholesale Trade2.71.7Forklift and material handling injuries
Retail Trade2.91.5Slips, trips, lifting injuries common
Transportation and Warehousing4.83.4Highest non-agriculture rate; lifting and vehicle
Healthcare and Social Assistance4.52.6Patient handling, exposure, workplace violence
Information0.80.5Office-based, low physical hazard
Finance and Insurance0.50.3Lowest among major sectors
Professional and Business Services1.00.5Office work plus field services blended
Accommodation and Food Services3.01.4Burns, cuts, slips, repetitive motion
Public Administration3.62.1Includes corrections, fire, public safety

Note: Source: U.S. Bureau of Labor Statistics, most recent published Survey of Occupational Injuries and Illnesses (SOII). Rates are per 100 full-time equivalent workers. Compare your TRIR and DART against your specific NAICS code, not the all-industry average. Rates fluctuate year to year; track your own trend alongside industry benchmarks. For educational reference only.

Frequently Asked Questions

What is the formula for TRIR?

TRIR = (Number of OSHA recordable cases x 200,000) / Total hours worked. The 200,000 multiplier represents 100 full-time employees working 2,000 hours each per year, so the result expresses incidents per 100 FTE workers. A company with 5 recordable injuries and 500,000 hours worked has a TRIR of (5 x 200,000) / 500,000 = 2.0.

What is a good TRIR rate?

The U.S. Bureau of Labor Statistics private-industry TRIR averages around 2.7. A TRIR below 1.0 is considered excellent and is the target for top-quartile performers. Construction averages 2.5, manufacturing 3.3, healthcare and social assistance 4.5, and warehousing 4.8. Always benchmark against your specific NAICS code rather than the all-industry figure.

How is LTIR different from TRIR?

TRIR counts ALL OSHA-recordable injuries: medical treatment beyond first aid, lost time, restricted duty, fatalities, and significant diagnoses. LTIR (Lost Time Incident Rate) counts only cases where an employee missed at least one full day of work. LTIR is always lower than TRIR for the same workplace and is the metric most commonly used internationally.

How do I calculate LTIFR?

LTIFR (Lost Time Injury Frequency Rate) uses the international 1,000,000-hour convention: LTIFR = (Lost Time Injuries x 1,000,000) / Total hours worked. A site with 3 lost-time injuries and 600,000 hours has an LTIFR of 5.0. Australian Safe Work and UK HSE both use this format. World-class performers report LTIFR below 1.0.

What is the DART rate and how does it differ from TRIR?

DART stands for Days Away, Restricted, or Transferred. The DART rate counts only cases serious enough to require time off, modified duty, or job transfer, which excludes minor recordables that only required medical treatment. Formula: (DART cases x 200,000) / Total hours. DART is always lower than TRIR. The BLS national DART average is around 1.7.

How do I count total hours worked for the formula?

Sum all hours actually worked by every employee during the reporting period: regular time, overtime, and temporary or contract hours that you supervise. Do NOT include vacation, sick leave, holidays, or other paid time not worked. Most employers pull this from payroll. A 50-person site averaging 2,000 productive hours per worker logs 100,000 total hours per year.

What is the severity rate and when should I use it?

The Severity Rate (also called Lost Workday Rate) measures injury severity rather than frequency. Formula: (Total lost workdays x 200,000) / Total hours worked. If your team had 30 lost workdays across 300,000 hours, the severity rate is 20. Track it alongside TRIR to see whether you are reducing both how often injuries occur AND how serious they are.

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