DART Rate Calculator

What Is a DART Rate?

DART stands for Days Away, Restricted, or Transferred. The DART rate is an OSHA safety metric that measures the number of workplace injuries and illnesses resulting in days away from work, job restriction, or job transfer per 100 full-time employees over a given period. It is a key indicator used by safety managers, HR professionals, and company leadership to evaluate the severity and frequency of workplace incidents.

How the DART Rate Is Calculated

The DART rate formula is standardized by OSHA for consistent safety reporting across industries. The calculation uses the total number of DART incidents and the total hours worked by all employees during the period.

Formula:

DART Rate = (Number of DART incidents × 200,000) ÷ Total hours worked by all employees

The constant 200,000 represents the baseline of 100 full-time employees working 40 hours per week for 50 weeks per year. This normalization allows companies of different sizes to compare safety performance on an equal footing.

What counts as a DART incident:

• Days away from work beyond the day of the injury
• Restricted work activity or job transfer due to injury or illness
• Cases involving both days away and restricted duty

Minor first aid treatments that do not result in lost time, restriction, or transfer are not counted as DART incidents.

How to Use This Calculator

To calculate your DART rate, you need two pieces of data from your OSHA 300 Log and your payroll records:

1. Total DART incidents — Count all recordable injuries and illnesses that resulted in days away, restricted work, or job transfer during the period.
2. Total hours worked — Sum of all hours actually worked by all employees during the same period. Do not include vacation, sick leave, holidays, or other paid time off.

Enter these numbers into the calculator fields and the tool will compute your DART rate instantly.

Example Calculation

A manufacturing facility with 150 employees reports 4 DART incidents over the course of a year. The total hours worked by all employees during that year is 300,000 hours.

DART Rate = (4 × 200,000) ÷ 300,000 = 2.67

This means the facility experienced approximately 2.67 DART incidents per 100 full-time employees. A rate below the industry average typically indicates effective safety programs, while a higher rate may signal the need for improved hazard controls or training.

Understanding Your DART Rate Result

The DART rate is a lagging indicator — it reflects past incidents rather than predicting future risk. However, it is widely used for benchmarking and trend analysis.

What the number means:

• Lower rates suggest fewer severe incidents and stronger safety practices.
• Higher rates may indicate systemic safety issues, inadequate training, or hazardous working conditions.
• Industry comparison is important — a rate that is high for one sector may be average for another. OSHA publishes industry-specific DART rate averages for reference.

Tracking your DART rate over multiple periods helps identify trends, evaluate the effectiveness of safety interventions, and support continuous improvement efforts.

Common Mistakes When Calculating DART Rate

• Including non-DART incidents — Only count cases that involve days away, restriction, or transfer. Minor injuries treated with first aid only should be excluded.
• Using incorrect hours — Total hours worked must exclude paid time off. Using total payroll hours instead of actual hours worked inflates the denominator and understates the rate.
• Counting the day of injury — The day the injury occurred is not counted as a day away. Only subsequent calendar days away from work are included.
• Mixing time periods — Ensure both incident counts and hours worked cover the same time frame (e.g., one calendar year).

Limitations of the DART Rate

The DART rate is a useful metric but has inherent limitations. It does not account for the severity of individual incidents — a single day away counts the same as months away. It also does not capture near misses, property damage, or minor injuries that do not result in lost time. For a complete safety picture, the DART rate should be used alongside other metrics such as the Total Recordable Incident Rate (TRIR) and leading indicators like safety training completion and hazard reporting rates.

Practical Use Cases for DART Rate

• OSHA reporting and compliance — Required for certain industries and company sizes as part of annual injury and illness reporting.
• Safety program evaluation — Measure whether new safety initiatives are reducing severe incidents over time.
• Bid and contract requirements — Many clients and general contractors require a DART rate below a specified threshold to qualify for projects.
• Internal benchmarking — Compare safety performance across departments, facilities, or shifts to identify high-risk areas.
• Insurance and risk management — Workers' compensation insurers may use DART rates to assess risk and set premiums.