TRIR — OSHA Total Recordable Incident Rate
TRIR = (recordable cases × 200,000) ÷ total hours worked
Source: OSHA 29 CFR 1904 · 200,000 ≈ 100 employees × 40 hr/wk × 50 wk/yr · Full guide
TRIR—
US private-industry avg: 2.7 · Construction: 2.5 · Mining: 1.7 · Manufacturing: 2.8 (BLS SOII 2024)
LTIFR — Lost Time Injury Frequency Rate
LTIFR = (LTI cases × 1,000,000) ÷ total hours worked
Source: ILO Resolution III · International standard, per million hours · LTIFR vs TRIR
LTIFR—
UK HSE all industries: ~1.0 · GCC oil & gas (IOGP): 0.4–0.8 · Construction (UAE OSHAD-SF): ~3.0
DART — Days Away, Restricted, or Transferred Rate
DART = (DART cases × 200,000) ÷ total hours worked
Source: OSHA 29 CFR 1904.7 · subset of TRIR; cases with days away or job transfer/restriction
DART—
US private-industry avg: 1.7 (BLS SOII 2024)
AFR — Accident Frequency Rate
AFR = (accidents × 1,000,000) ÷ total hours worked
Generic frequency rate per million hours; UK HSE / GCC default. Use this when "accident" is broader than OSHA recordable.
AFR—
Severity Rate — Days Lost per Million Hours
Severity = (days lost × 1,000,000) ÷ total hours worked
Source: ILO Resolution III · how serious the injuries are, on average
Severity Rate—
TRIFR — Total Recordable Injury Frequency Rate
TRIFR = (recordable injuries × 1,000,000) ÷ total hours worked
Australia / NZ / IOGP standard. Same numerator as TRIR but per-million-hours basis. Comparison
TRIFR—
IOGP global oil & gas: ~0.83 · Australian construction: ~5.2 (Safe Work Australia)