DART Rate Calculator
Compute the DART rate (Days Away, Restricted, or Transferred): DART = qualifying injury cases x 200,000 / total hours — the frequency of severe injuries.
Input Data
Results
At a glance:DART (Days Away, Restricted, or Transferred) measures the frequency of 'severe' work injuries — those causing time away, restricted duty, or transfer. DART rate = (DART cases x 200,000) / total hours; 200,000 = 100 FTEs x 2,000 hrs, so the rate = cases per 100 FTEs per year. DART is the severe subset of TRIR, so DART ≤ TRIR. WARNING: 'recordable/DART' follows professional standards (e.g. OSHA); HK Labour Department criteria may differ. Education, not advice.
Formula
DART = (DART cases × 200,000) / total hours worked.
200,000 = 100 FTEs × 2,000 hrs/year, so the rate = cases per 100 FTEs per year.
$$DART = \dfrac{DART\ cases \times 200{,}000}{Total\ hours\ worked}$$$$DART \leq TRIR$$How to Use
- Enter the DART injury case count.
- Enter total hours worked.
- View the standardised DART rate.
FAQ
What is the DART rate and how is it computed?
DART is an occupational-safety core metric: Days Away, Restricted, or Transferred — injuries severe enough to cause leave (Days Away), limited duties (Restricted), or reassignment (Transferred). Formula: DART rate = (DART cases x 200,000) / total hours. The 200,000 constant = 100 full-time employees x 2,000 hours/year, standardising all firms to 'per 100 FTEs per year'. Example: 5 cases, 250,000 hours → (5 x 200,000)/250,000 = 4, i.e. ~4 severe injuries per 100 FTEs per year.
How is DART different from TRIR?
Same formula (cases x 200,000 / hours) but different numerator. TRIR covers ALL recordable injuries/illnesses (any needing more than first aid, lost consciousness, diagnosed occupational illness), regardless of severity. DART counts only the severe subset (days away, restricted, or transferred). So every DART case is recordable (in TRIR) but not vice versa (a minor injury needing simple treatment, employee works normally, is in TRIR not DART). Thus DART ≤ TRIR. TRIR shows overall frequency; DART focuses on injuries with real impact. Track both: high TRIR but low DART = many minor, few severe; high DART/TRIR ratio = severe cases dominate, warrant attention.
What is a good DART rate, and caveats?
No one-size-fits-all standard — risk varies hugely by industry (construction/manufacturing/logistics naturally higher than office). Compare with industry benchmark, not across industries; lower is better; track your own trend over time. Caveats: (1) use correct definitions per OSHA etc.; (2) total hours must be accurate (exclude leave); (3) small firms' rates swing wildly on one case; (4) it is a lagging indicator — pair with leading ones (inspections, near-miss reporting). For formal reporting, follow the local authority (HK Labour Department).
What does DART/TRIR ratio reveal?
DART divided by TRIR is a 'severity' indicator — what share of recordable injuries were severe. Example TRIR 4, DART 1.5 → 37.5% of recordables were severe. Read cases: high TRIR, low DART ratio = many minor; low TRIR but high DART ratio = infrequent but severe (high-consequence risk like falls, machinery) — prioritise engineering controls. Small-firm ratios swing; watch multi-period averages; it is lagging, so pair with leading indicators.
Which injuries count as DART, and how to count days?
A case counts if it causes any ONE of: (1) Days Away — couldn't work, took leave (even one day after the injury); (2) Restricted work — returned but can't do all normal duties (e.g. no heavy lifting); (3) Transferred — reassigned due to injury. Simple-treatment-and-normal-work cases are recordable (TRIR) but not DART. Day counting: typically from the day AFTER the injury (calendar days, not work days), often capped (e.g. 180 days). Note the DART numerator counts CASES, not total lost days (days feed other severity metrics). Follow the local authority (HK Labour Department) for classification.
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References
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.