How do you calculate Lost Time Injury Rate?

Multiply lost-time cases by 200,000 and divide by total hours worked. With 2 lost-time cases and 500,000 hours, that is 2 x 200,000 / 500,000 = an LTIR of 0.8 per 100 workers.

What is the difference between LTIR and TRIR?

TRIR counts every OSHA-recordable case; LTIR counts only cases where the worker missed time from work. LTIR is always a subset, so it is lower — in the example, an LTIR of 0.8 against a higher overall recordable rate.

What is a good Lost Time Injury Rate?

Lower is better. Strong manufacturing programs run an LTIR under 1.0, and the worked example's 0.8 falls in that range. World-class operations target well below 0.5.

Does the day of injury count as lost time?

Under OSHA's day-count rules you start counting days away the day after the injury, not the day it occurred. But the case itself becomes a lost-time case as soon as the worker misses any subsequent scheduled day.

Is LTIR the same as lost time injury frequency rate?

They are close but not identical. LTIR here uses the 200,000-hour (per-100-workers) base common in the US. Some countries use a 1,000,000-hour base for an LTIFR, so the same injuries yield a different number.

Why use 200,000 hours in the formula?

It equals 100 employees working 2,000 hours a year, normalizing any workforce to a per-100-worker rate so a small shop and a large plant can be compared on equal footing.

Safety & Workforce calculator

Lost Time Injury Rate Calculator

The Lost Time Injury Rate (LTIR) measures how many injuries serious enough to keep a worker away from their next scheduled shift occur per 100 full-time-equivalent employees per year. Unlike the broader recordable rate, LTIR isolates the injuries that actually cost you production days and drive workers' compensation claims, making it a sharper indicator of injury severity. Safety leaders, operations managers, and insurers watch LTIR closely because it correlates directly with lost output and claim cost. A site can have a flat recordable rate but a rising LTIR — a signal that the injuries that do happen are getting more serious.

What this calculator does

Calculate LTIR (lost-time injury rate) for Safety & Workforce from lost-time cases and total hours worked, using the OSHA 200,000-hour basis.
Use it to benchmark safety performance for Safety & Workforce against OSHA and industry averages.
It computes your lost-time injury rate per 100 full-time workers from lost-time cases and total hours worked.

Formula used

LTIR = lost-time cases × 200,000 ÷ total hours worked
200,000 = 100 full-time workers × 2,000 hours per year

Inputs explained

Lost-time cases: Number of lost-time cases in the period (usually a calendar year).
Total hours worked: All employee hours worked in the same period (overtime included).

How to use the result

Use it monthly or quarterly when you need to track injury severity, support workers' comp reviews, or report a metric that excludes minor recordables.
Definitions of 'lost time' vary by region and company — some count any day away, others exclude the day of injury — so always confirm the counting rule before benchmarking against another organization.

Current U.S. benchmarks

Manufacturing hourly earnings average $30.27 (BLS, Jun 2026), up 4.4% from a year earlier. Median machinist pay is $28.24/hr (OEWS 2025), with state medians on each state page. Manufacturers have 529k open positions nationally (BLS JOLTS).

Common questions

How do you calculate Lost Time Injury Rate? Multiply lost-time cases by 200,000 and divide by total hours worked. With 2 lost-time cases and 500,000 hours, that is 2 x 200,000 / 500,000 = an LTIR of 0.8 per 100 workers.
What is the difference between LTIR and TRIR? TRIR counts every OSHA-recordable case; LTIR counts only cases where the worker missed time from work. LTIR is always a subset, so it is lower — in the example, an LTIR of 0.8 against a higher overall recordable rate.
What is a good Lost Time Injury Rate? Lower is better. Strong manufacturing programs run an LTIR under 1.0, and the worked example's 0.8 falls in that range. World-class operations target well below 0.5.
Does the day of injury count as lost time? Under OSHA's day-count rules you start counting days away the day after the injury, not the day it occurred. But the case itself becomes a lost-time case as soon as the worker misses any subsequent scheduled day.
Is LTIR the same as lost time injury frequency rate? They are close but not identical. LTIR here uses the 200,000-hour (per-100-workers) base common in the US. Some countries use a 1,000,000-hour base for an LTIFR, so the same injuries yield a different number.

Last reviewed 2026-05-12.