What Is Lost Time Incident Rate (LTIR)?
Learn what lost time incident rate (LTIR) means, how to calculate workplace injuries causing missed days per 100 employees (formula: incidents × 200,000 ÷ hours worked), industry benchmarks (manufacturing 0.9, construction 1.8, healthcare 1.2), and proven safety improvement strategies.
What Is Lost Time Incident Rate?
Lost Time Incident Rate (LTIR) is a safety metric measuring the frequency of workplace injuries or illnesses resulting in at least one missed workday beyond the date of injury, calculated per 100 full-time employees annually. It provides a standardized measure for comparing safety performance across organizations and industries.
LTIR focuses on severe injuries requiring time off work, distinguishing it from broader metrics that include minor first-aid cases.
Quick Answer
Lost time incident rate (LTIR) measures workplace injuries causing missed workdays per 100 employees annually using the formula: (Number of lost time incidents × 200,000) ÷ Total hours worked. National average is 1.1; construction averages 1.8, manufacturing 0.9, healthcare 1.2.
According to the U.S. Bureau of Labor Statistics, private sector employers reported 1.1 lost time incidents per 100 full-time workers in 2023, down from 1.3 in 2013. Rates vary dramatically by industry—construction averages 1.8, warehousing 2.5, while professional services average 0.2.
How Do You Calculate Lost Time Incident Rate?
The LTIR Formula
LTIR = (Number of lost time incidents × 200,000) ÷ Total hours worked by all employees
Where:
- Number of lost time incidents: Workplace injuries/illnesses resulting in at least one full day away from work
- 200,000: Hours worked by 100 full-time employees annually (40 hours/week × 50 weeks × 100 workers)
- Total hours worked: Actual hours worked by all employees during the measurement period
Calculation Example
Organization with 150 employees:
- Total hours worked in year: 300,000
- Lost time incidents: 4
LTIR = (4 × 200,000) ÷ 300,000 = 2.67
This organization experienced 2.67 lost time incidents per 100 full-time employees, higher than the national average of 1.1.
What Counts as a Lost Time Incident?
Included: Severe sprains/strains, fractures, lacerations requiring stitches and recovery time, back injuries preventing work, burns, occupational illnesses causing absence, head injuries/concussions.
Excluded: Injuries where employee works restricted duty or modified schedule, medical treatment with next-day return to full duty, first aid cases, commuting injuries, pre-existing conditions unrelated to work.
Key distinction: The injury must result in at least one full workday away beyond the injury date.
What Are Industry Benchmarks for LTIR?
Industry Averages (2023 BLS Data)
| Industry | LTIR | Common Causes |
|---|---|---|
| Construction | 1.8 | Falls, struck-by, equipment injuries |
| Warehousing/Storage | 2.5 | Material handling, slips/trips/falls |
| Manufacturing | 0.9 | Machinery, assembly lines, ergonomics |
| Healthcare/Social Assistance | 1.2 | Patient handling, falls, violence |
| Retail | 1.0 | Wet floors, stocking, customer areas |
| Transportation | 2.1 | Driving, loading/unloading |
| Agriculture | 2.8 | Tractors, livestock, pesticides |
| Professional Services (office) | 0.2 | Stairs, parking lots |
| National Private Sector Average | 1.1 | Varies |
What Is a Good LTIR?
Excellent: 0.5 or lower—significantly below industry average
Good: Below industry average—effective safety practices
Average: Within 10% of industry benchmark
Concerning: 20–50% above industry average—requires intervention
Critical: 50%+ above industry average—immediate action needed
What Is the Impact of High Lost Time Incident Rate?
Workers Compensation Costs
Lost time claims average $41,000 versus $4,000 for medical-only claims—10× higher. Organizations with LTIR significantly above industry average face experience modification rates (EMR) above 1.0, increasing premiums 20–40%.
Example: A 100-employee manufacturer with 2.0 LTIR (vs 0.9 industry average) might pay $80,000 annual workers comp premium. Reducing LTIR to 1.0 could drop premiums to $55,000—$25,000 annual savings.
Productivity and Operational Losses
Absent injured workers create absenteeism requiring voluntary overtime for remaining workers, temporary replacements with lower productivity, and work delays when specialized skills are unavailable. Quality issues increase from rushed work or inexperienced replacements, impacting employee rosters and scheduling.
Employee Morale and Retention
High injury rates create fear about personal safety, reducing employee empowerment and increasing turnover. Frequent injuries signal management doesn’t prioritize worker well-being, damaging trust, impacting workplace behavior, and making recruitment difficult.
Legal and Regulatory Consequences
Severe injuries trigger OSHA investigations, potentially resulting in citations and fines. Injured workers may pursue third-party lawsuits if gross negligence is alleged. Patterns of injuries may reveal safety standard violations.
How Does LTIR Differ from Other Safety Metrics?
LTIR vs TRIR: LTIR counts only injuries causing missed workdays. TRIR counts all OSHA-recordable injuries including medical treatment, restricted work, and job transfers. TRIR is always higher than LTIR.
LTIR vs DART Rate: LTIR counts only days away from work. DART (Days Away, Restricted, or Transferred) includes days away plus restricted duty days. DART is slightly higher.
LTIR vs Severity Rate: LTIR measures frequency (how often). Severity Rate measures impact (total days lost per 100 workers). Two organizations with identical LTIR can have vastly different severity rates.
How Do You Reduce Lost Time Incident Rate?
Conduct Comprehensive Hazard Assessments
Break down each job into steps, identify hazards, develop controls. Conduct regular workplace inspections, encourage near-miss reporting, and prioritize highest-risk activities.
Implement Strong Safety Training
Provide comprehensive new hire orientation before starting work, job-specific training on safe procedures and equipment operation, annual refresher training, frequent toolbox talks, and competency verification through testing.
Provide Proper Equipment and Controls
Install engineering controls (machine guards, fall protection, ventilation), supply appropriate PPE and enforce use, make ergonomic improvements (adjustable workstations, mechanical assists), and implement regular equipment maintenance.
Create Accountability and Culture
Ensure leadership visibly prioritizes safety, hold supervisors accountable for team performance, involve frontline workers in safety committees, celebrate safe behaviors and milestones, and consistently enforce safety rules.
Investigate and Learn from Incidents
Conduct thorough root cause analysis for every lost time incident, implement corrective actions, review incidents quarterly to identify patterns, and communicate lessons learned across the organization.
Focus on High-Risk Activities
Material handling: Provide mechanical assists, train proper lifting technique, redesign processes.
Slips, trips, falls: Improve housekeeping, repair surfaces, enhance lighting, install handrails.
Equipment operation: Enhanced training, pre-use inspections, machine guarding, lockout/tagout.
Working at heights: Fall protection systems, proper ladder use, harness requirements.
Track Leading Indicators
Monitor safety observation completion rates, training completion, near-miss reporting volume, corrective action closure rates, and safety meeting attendance.
Managing Lost Time Incidents When They Occur
OSHA Recordkeeping Requirements
Record injury on OSHA Form 300 within 7 days, complete Form 301 incident report, display Form 300A summary February 1–April 30, and submit data electronically if 100+ employees in high-hazard industries.
Return to Work Programs
Offer modified duty allowing injured workers to contribute while healing, phase workers back to full duties gradually, maintain contact with absent workers, and provide reasonable accommodations.
Effective return-to-work programs can reduce lost workdays by 30–50%, lowering both LTIR and workers compensation costs.
The Bottom Line
Lost time incident rate measures workplace injuries requiring at least one missed workday beyond the injury date, calculated per 100 full-time employees using: (Number of lost time incidents × 200,000) ÷ Total hours worked. National average is 1.1, with construction averaging 1.8, warehousing 2.5, manufacturing 0.9, healthcare 1.2, and professional services 0.2.
High LTIR drives workers compensation premium increases of 20–40%, with lost time claims costing 10× more than medical-only claims ($41,000 vs $4,000). Additional impacts include productivity losses, reduced morale, recruitment difficulties, OSHA inspection risk, and operational disruption.
Reduce LTIR through comprehensive hazard assessments, strong safety training, proper equipment and engineering controls, safety culture with leadership commitment, thorough incident investigation, focus on high-risk activities, and tracking leading indicators. Effective return-to-work programs offering modified duty can reduce lost workdays by 30–50%.
Try ShiftFlow’s scheduling tools to ensure adequate coverage, prevent fatigue-related injuries, and support modified duty schedules during recovery.
Sources
- U.S. Bureau of Labor Statistics – Employer-Reported Workplace Injuries
- Occupational Safety and Health Administration – Recordkeeping Requirements
- National Safety Council – Injury Facts and Statistics
Further Reading
- Absenteeism Management – Handling unplanned absences including injuries
- Workplace Behavior Standards – Creating safety culture
- Mandatory Overtime Risks – Fatigue and injury connections
Frequently Asked Questions
What is lost time incident rate?
Lost time incident rate (LTIR) is a safety metric measuring workplace injuries or illnesses resulting in at least one missed workday beyond the injury date, calculated per 100 full-time employees annually. It tracks the frequency of serious injuries requiring time off work.
How do you calculate lost time incident rate?
LTIR = (Number of lost time incidents × 200,000) ÷ Total hours worked by all employees. The 200,000 represents hours worked by 100 full-time employees annually. Example: 3 incidents and 500,000 hours = (3 × 200,000) ÷ 500,000 = 1.2 LTIR.
What is a good lost time incident rate?
Good LTIR depends on industry: manufacturing averages 0.9, construction 1.8, retail 1.0, healthcare 1.2, warehousing 2.5. Rates below industry average are good; rates 20%+ above average indicate safety problems. National private sector average is 1.1 lost time incidents per 100 workers annually.
What counts as a lost time incident?
Workplace injuries or illnesses resulting in at least one full day away from work beyond the injury date. Includes severe sprains, fractures, lacerations requiring stitches, back injuries, burns, and occupational illnesses causing absence. Excludes injuries where employees work restricted duty without missing days.
What is the difference between LTIR and TRIR?
LTIR counts only injuries causing missed workdays. TRIR counts all OSHA-recordable injuries including medical treatment, restricted work, job transfers, and lost time. TRIR is always higher than LTIR because LTIR is a subset.
How does high LTIR affect workers compensation costs?
Organizations with LTIR 30–50% above industry average face workers compensation premium increases of 20–40%. Lost time claims cost 10× more than medical-only claims ($41,000 vs $4,000). A manufacturer reducing LTIR from 2.0 to 1.0 can save $50,000–$150,000 annually in workers comp premiums.
How do you reduce lost time incident rate?
Reduce LTIR through comprehensive hazard assessments, strong safety training, proper equipment and engineering controls, accountability and safety culture, thorough incident investigation and corrective actions, focusing on high-risk activities, and implementing return-to-work programs reducing lost workdays.
What is the difference between LTIR and DART rate?
LTIR counts only days away from work. DART Rate counts days away plus restricted duty days plus job transfers due to injury. DART is slightly higher than LTIR because it includes restricted duty cases where workers remain on-site performing modified duties.
