Lost Time Injury Incident Rate

Lost time injury incident rate, abbreviated as LTIIR, is the frequency of workplace incidents that result in lost time from work.  It is a variation of injury rate metrics that specifically focuses on incidents causing employees to miss work beyond the day of the incident.

The lost time injury incident rate helps organizations assess the frequency of incidents leading to lost work time, providing insights into workplace safety performance.  A lower LTIIR indicates fewer incidents resulting in lost time relative to the number of hours worked, suggesting better safety practices.  Conversely, a higher LTIIR indicates a higher frequency of incidents leading to lost time and may signal areas where safety measures need improvement or where specific hazards require attention

 

Lost Time Injury Incident Rate formula The constant is usually 200,000 work hours, representing the equivalent of 100 full time employees working 40 hours per week for 50 weeks in a year.  However, this constant may vary depending on the organization or jurisdiction.

\( LTIIR =  (TNLTI \;/\; TNHW) \; 200,000 \)

Symbol

\( LTIIR \) = lost time injury incident rate

\( TNLTI \) = total number of lost time incidents

\( TNHW \) = total number of hours worked by all employees