The Days Away, Restricted, or Transferred (DART) rate is a standardized metric used to measure the severity of work-related injuries and illnesses within a workplace. This figure reflects the impact of incidents that result in an employee being unable to perform their regular duties. The calculation is federally mandated by the Occupational Safety and Health Administration (OSHA) for certain employers to track and assess their safety record, typically over a calendar year. Understanding how to accurately calculate this rate allows businesses to benchmark their performance and identify areas needing safety intervention.
Required Data for DART Calculation
Before beginning the calculation, a company must gather two primary categories of data: the count of qualifying incidents and the total labor hours worked. The official record for tracking qualifying incidents is the OSHA 300 Log, formally known as the Log of Work-Related Injuries and Illnesses. This log is required under 29 CFR 1904 and catalogs all recordable incidents for the year.
The second necessary piece of information is the total number of hours worked by all employees during the reporting period. Accurate recordkeeping of both injury outcomes and employee time is mandatory for compliance and ensures the DART rate is reliable for regulatory reporting.
Identifying DART Cases (The Numerator)
The numerator of the DART rate calculation is the total number of recordable incidents that resulted in days away from work, restricted work, or job transfer. A recordable incident is any work-related injury or illness that meets specific criteria, such as requiring medical treatment beyond first aid or resulting in loss of consciousness. The DART rate specifically isolates those cases where the severity was high enough to alter an employee’s normal work status.
A “Days Away from Work” case is counted when an employee misses one or more full calendar days following the injury. The day the injury occurred is not counted, but all subsequent calendar days, including weekends and holidays, are counted until the employee returns to work.
A “Restricted Work” case occurs when an employee is temporarily limited from performing routine job functions or cannot work the full scheduled shift. A “Transfer to Another Job” case is counted when the injured employee is moved to a different job, even for a portion of the workday, because of the injury. If a physician recommends restricted work, the case must be recorded as such, regardless of whether the employee follows the recommendation. These three outcomes are summed up to form the numerator.
Calculating Total Employee Labor Hours (The Denominator)
The denominator of the DART calculation is the Total Employee Labor Hours, representing the aggregate hours worked by all employees over the reporting period. This figure must encompass the hours worked by every individual on the payroll, including full-time, part-time, seasonal, temporary, and supervisory employees.
Employers must strictly exclude non-work time, such as vacation, sick leave, holidays, or any other paid time off, even if employees were compensated. For salaried staff, employers must estimate the hours actually worked, often using payroll records or a standard work year estimate (e.g., 2,000 hours). Contract worker hours are generally excluded but must be included if the employer supervises the contractor’s work activities daily.
Step-by-Step DART Rate Calculation
The DART rate is calculated using a standard OSHA formula to ensure comparability across different company sizes and industries. The formula is: (Number of DART Cases x 200,000) / Total Employee Labor Hours. This calculation converts raw incident data into a standardized rate representing the number of DART cases per 100 full-time equivalent workers.
The 200,000 multiplier serves as the base for the calculation. This figure represents the total hours 100 full-time employees would work in a year, assuming 40 hours per week for 50 weeks. Using this constant allows companies with different labor hour totals to calculate a rate comparable to national and industry averages.
For example, a company had 8 DART cases and 400,000 employee labor hours in a calendar year. The calculation is (8 x 200,000) / 400,000, resulting in a DART rate of 4.0. This means the company experienced four DART cases for every 100 full-time equivalent employees.
Interpreting and Benchmarking Your DART Rate
The resulting DART number signifies the rate of serious injuries and illnesses that disrupted normal work duties per 100 full-time employees. A lower DART rate suggests fewer severe injuries requiring time away or job modification, reflecting stronger safety performance.
To properly benchmark performance, companies must compare their DART rate against the average rate for their specific industry sector. This industry average is published annually by the Bureau of Labor Statistics (BLS) using the company’s North American Industry Classification System (NAICS) code. A rate higher than the national industry average signals that the existing safety program may require improvements.