The Occupational Safety and Health Administration (OSHA) has established standard metrics to measure workplace safety, two of the most critical being Days Away, Restricted or Transferred rate (DART) and Total Recordable Incident Rate (TRIR).

These metrics measure how often incidents resulting in medical treatment beyond first aid and incidents resulting in days away from work, restricted duty, or job transfers occur, relative to the hours worked. They are considered lagging indicators, reflecting past incident history, and are calculated from data that companies record on OSHA injury logs (OSHA Form 300/300A) each year.

In this guide, we’ll compare the two metrics side by side, show examples of how they work in practice, explore why they matter for compliance and operations, examine their limitations, and close with how Highwire incorporates them into its safety evaluations.

We’ll also finish by defining TRIR and DART, then walk through how each is calculated and used in construction.

What is DART?

DART stands for Days Away, Restricted or Transferred. The DART rate zeros in on the more serious subset of recordable incidents. Those that are severe enough to result in a worker missing days of work, doing restricted/light duties, or being transferred to a different job role due to injury.

DART measures the rate of workplace injuries that significantly disrupt normal work. While TRIR counts all recordable cases, DART counts only the cases with days away or work modifications, making it a focused metric for the impact of injuries on operations.

All DART cases are by definition OSHA-recordable, but they represent the more severe injuries/illnesses that affect an employee’s ability to perform their regular job. For example, if a construction worker sprains their back and cannot lift heavy materials for a week (restricted duty), that incident would count toward their DART rate. If another worker suffers a more minor injury like a cut requiring stitches but returns to full duty the next day, it’s recordable (and impacts their TRIR) but not a DART case because it didn’t cause time away or restrictions.

How is DART Calculated?

The DART rate uses a formula structurally similar to TRIR, again normalizing to 200,000 hours of work exposure. The formula is:

Here, “Number of DART cases” is the count of recordable incidents that resulted in days away, restricted duty, or transfer. Using the earlier example company (200,000 work hours in a year), if 2 out of its 5 recordable incidents were DART cases, the DART rate would be (2 × 200,000) / 200,000 = 2.0. This means 2 cases per 100 workers caused lost or restricted time–aligning with the notion that DART is a subset of the total incidents.

In practice, a company’s DART rate will always be equal to or lower than its TRIR (since you’re filtering down to the more severe incidents). Based on data from the Bureau of Labor Statistics, the average DART rate in construction is around 1.5 cases per 100 workers.

How to Use DART in Construction

The DART rate is a critical metric for understanding the severity and operational impact of safety incidents. Because it highlights cases that interfere with production (through absences or light-duty assignments), DART is directly tied to productivity and project scheduling.

Construction safety managers analyze DART rates to pinpoint where serious injuries are happening and to gauge the effectiveness of controls in preventing severe harm. For instance, comparing DART rates across multiple projects or departments can reveal which job sites or activities have higher rates of severe injuries, focusing attention on those trouble spots. Additionally, DART gives management a tangible way to quantify lost work time.

A rising DART rate is a clear call to action. It often points to underlying issues like unsafe conditions, gaps in training, or inadequate planning for high-risk tasks. Employers track DARTrates closely over time to measure improvements. If safety initiatives are effective, both TRIR and DART rates should fall.

What is TRIR (Total Recordable Incident Rate)?

Total Recordable Incident Rate (TRIR)–also called Total Case Incident Rate (TCIR) or simply the OSHA Recordable Rate–is a standardized measure of how often a company experiences OSHA-recordable injuries and illnesses, normalized per 100 full-time workers. In essence, TRIR answers: “How many recordable incidents did we have for a given amount of work exposure?”

OSHA defines a recordable incident as any work-related injury or illness that results in death, loss of consciousness, days away from work, restricted work or job transfer, or medical treatment beyond first aid. This means everything from a serious accident leading to lost workdays to a more minor injury just requiring stitches (beyond first aid) is “recordable.” TRIR casts a wide net by including all such incidents, both major and minor, that meet OSHA’s recordability criteria.

How is TRIR Calculated?

TRIR is calculated with a simple formula that scales the number of incidents to a standard labor exposure of 200,000 hours (which is roughly equivalent to 100 full-time workers working a year).

The formula is:

The 200,000-hour factor allows companies of different sizes to be compared on an equal basis. For example, if a construction firm had 5 recordable injuries in a year and its employees worked 200,000 hours in that period, the TRIR would be (5 × 200,000) / 200,000 = 5.0. In plain terms, that translates to 5 recordable cases per 100 full-time workers in a year.

Lower is better. A low TRIR indicates fewer incidents relative to hours worked, whereas a high TRIR indicates a higher frequency of injuries.

To learn more about how TRIR is calculated, refer to our guide: Understanding TRIR: What It Is, How to Calculate It, and Why It Matters.

How to Use TRIR In Construction

Safety professionals and executives track TRIR as a broad indicator of overall safety performance. Because it captures all recordable incidents, TRIR provides a big-picture view of the company’s injury rate. A rising TRIR over time is a warning sign that safety performance may be deteriorating. It often signals the need for intervention, such as additional training or process changes. Conversely, a declining TRIR demonstrates improvements in safety programs.

TRIR is widely used for internal trend analysis (e.g., year-over-year performance) and external benchmarking. The Bureau of Labor Statistics (BLS) publishes average incident rates by industry, allowing construction firms to compare their TRIR against industry peers. Overall, TRIR is one of the most important lagging metrics to gauge if a company is handling jobsite risks effectively.

DART and TRIR Key Differences

While both TRIR and DART are OSHA-standard incident rates that use the same formula structure, they measure slightly different aspects of workplace injuries.

Here’s a comparison of the two metrics and what they include.

Scope of Incidents: TRIR counts all OSHA-recordable incidents, including both minor and major injuries (anything beyond first aid). DART drills in on a subset of those recordable cases. Specifically, the ones with the most severe outcomes: days away from work, restricted duties, or job transfers. Every DART case is also recordable, but not every recordable case qualifies as DART.

Formula and Value: Both are calculated per 200,000 hours worked. Because DART uses a smaller subset of incidents as its numerator, its value will always be less than or equal to TRIR for the same period. For example, if a company experiences several medical-treatment cases without lost time, those would increase TRIR but not DART. The difference between the two rates simply reflects how many recordable injuries resulted in time away or work restrictions.

Use Cases: TRIR allows organizations to measure the frequency of all recordable incidents, providing a snapshot of how often incidents are occurring.. DART, by contrast, focuses on the portion of incidents that caused employees to miss work or be reassigned–in other words, the more severe subset of safety cases. Both are lagging indicators that together provide a fuller picture of workplace safety outcomes.

In summary, TRIR captures the total number of recordable injuries, while DART drills in on the subset involving more serious consequences such as lost workdays, restricted duty, or job transfers.

Examples of DART and TRIR in Practice

To illustrate the difference between these metrics, let’s look at a realistic scenario:

Imagine a mid-size construction company with about 100 full-time workers (roughly 200,000 work hours in a year). In the past year, this company had 5 OSHA-recordable incidents in total. Out of these 5 cases, 2 incidents resulted in days away from work or restricted duty for the injured employees. The other 3 were recordable only because they needed medical treatment beyond first aid, but the workers returned to full duty immediately.

• TRIR Calculation: Using the formula, TRIR = (5 × 200,000) / 200,000 = 5.0. This means the company experienced the equivalent of 5 recordable injuries per 100 workers over the year. Those 5 include everything from relatively minor injuries (e.g. one requiring stitches) to the more serious ones.

• DART Calculation: DART = (2 × 200,000) / 200,000 = 2.0. This reflects 2 cases per 100 workers where injuries actually caused the person to miss work or be on restricted duty. In our scenario, these 2 were the more severe incidents (one involved an absence from work and the other required light duty assignment during recovery).

From this example, you can see the DART rate (2.0) is lower than the TRIR (5.0), since DART only counts the subset of incidents that had serious outcomes. The TRIR of 5.0 captures the overall injury frequency (five people were hurt enough to need more than first aid), whereas the DART rate of 2.0 focuses on the two cases with the most severe outcomes, keeping workers off their normal job duties.

This gap between TRIR and DART is typical. It tells us that several incidents, while recordable, did not result in days away from work, restricted duty, or job transfers. If, hypothetically, all 5 injuries had caused days away, restrictions, or job transfers, then the TRIR and the DART rate would both be 5.0. But in many cases, the TRIR will be higher, and the difference between the two numbers effectively indicates how many incidents resulted in less severe outcomes.

To put it another way, TRIR answers “how many people suffered an injury” while DART answers “how many people couldn’t work (or fully work) because of their injury."

By examining both metrics, you gain insight into not just how often injuries happen, but also how severe their outcomes are.

Why DART and TRIR Matter in Construction

Maintaining low TRIR and DART rates isn’t just about bragging rights. It has real consequences for compliance, business competitiveness, and the bottom line.

Here’s why these metrics are so important in construction.

• Benchmarking and Reputation: TRIR and DART allow construction companies to benchmark their safety performance against industry averages and competitors. The BLS publishes annual average rates (for instance, recent data showed an average TRIR of around 3.1 for construction companies). Firms that maintain rates better (lower) than the industry average can advertise that achievement, which enhances their reputation for safety. On the flip side, a contractor with a TRIR or DART significantly worse than average may stand out. In an industry where clients and partners care about safety records, being above average can be a competitive advantage. Internally, benchmarking year over year also fosters a culture of continuous improvement (e.g., aiming to beat last year’s safety record).

• Insurance and Cost Impact: Safety metrics have a direct line to insurance costs and overall financial performance. A high frequency of injuries (high TRIR) or severe injuries (high DART) will drive up workers’ compensation claims, which in turn can raise a company’s Experience Modification Rate (EMR) and insurance premiums. Essentially, insurers see a high TRIR/DART as an indication of risk, and they charge more to cover that risk. Conversely, a strong safety record can lower insurance costs over time. Keeping DART low is especially impactful because it means fewer lost-time injuries, which are often the costliest. Moreover, injuries bring indirect costs: lost productivity, project delays, overtime for replacement workers, and potential legal liabilities. By preventing incidents (thus keeping TRIR/DART down), construction companies avoid these costs and improve their profitability.

• Client Prequalification: Construction firms are frequently required to submit their TRIR and DART rates when bidding for projects or getting approved as vendors. Many project owners, general contractors, and government contracts have prequalification standards. They may disqualify or scrutinize contractors with a TRIR or DART above a certain threshold. In fact, most formal prequalification systems look at lagging indicators like TRIR and DART to judge if a contractor is “safe enough” to work on a project. A low TRIR/DART can be the difference between winning a contract or being passed over. Clients see these numbers as shorthand for how serious a contractor is about safety. Thus, excelling in these metrics opens up business opportunities, whereas poor rates can shut you out of lucrative jobs.

• Operational Excellence: Safety and operations go hand-in-hand. A high DART means frequent disruptions. Workers off the job or on light duty can slow down projects and strain the remaining crew. By tracking and minimizing DART, companies are essentially minimizing unplanned downtime due to injuries. This leads to more predictable project schedules and better labor productivity. A high TRIR can indicate systemic issues that affect morale and efficiency. If workers see colleagues getting hurt often, it can create distractions or hesitations that also impact productivity. On the positive side, a strong safety record (low TRIR/DART) contributes to smoother operations: crews can focus on their work rather than dealing with accidents, and experienced workers remain on the job. Safety metrics also provide data to support operational decisions. For example, management can use DART metrics to quantify how many work hours were lost to injuries, strengthening the case for investments in safety training or better equipment (as these investments directly protect manpower and project timelines). In short, focusing on TRIR and DART is part of running an efficient, high-quality construction operation, not just a paperwork exercise.

Limitations of DART and TRIR as Safety Performance Metrics

DART and TRIR have notable drawbacks as primary safety indicators. Both are lagging measures that look backward at past incidents, offering only a narrow snapshot of injuries rather than an ongoing risk profile. Moreover, they rely on self-reported injury logs that can be underreported or manipulated, and they count all recordable injuries equally regardless of severity. This means a minor injury and a major accident carry the same weight in the rate, while critical warning signs like near-misses or unsafe conditions are ignored by these measures. As a result, a low DART rate or TRIR alone can paint an overly simplistic or misleading picture of safety performance and has little predictive value for future accidents.

DART and TRIR figures can also be gamed. Companies under pressure to maintain low rates might discourage reporting or use aggressive case management (e.g. returning injured workers to light duty) to keep incidents off the official record. Thus, a “good” rate is not always proof of a strong safety program. It could simply reflect hidden injuries or a culture of silence rather than true risk reduction. Smaller contractors and short-duration projects also experience large swings in these metrics from a single incident, making one year’s rate statistically unreliable for comparisons.

Construction industry dynamics further expose the limitations of these metrics. High workforce turnover and heavy use of subcontractors mean that the personnel and safety practices on site change frequently, making historical incident rates less indicative of current risk. A general contractor’s TRIR may not capture injuries among subcontractor or temporary workers, and those short-term workers might even hesitate to report incidents due to job insecurity.

Overemphasizing DART or TRIR targets can also undermine safety culture. If contract bids or bonuses hinge on these numbers, organizations may unintentionally incentivize keeping injuries off the books instead of openly addressing hazards.

In summary, while DART and TRIR are useful baseline indicators of past performance, they often fail to reflect true safety culture or risk on a project. They should be balanced with proactive safety metrics and candid reporting practices to present a more complete picture of risk.

How Highwire Uses DART and TRIR in Safety Evaluations

Highwire’s safety risk management platform integrates TRIR and DART as core components of its contractor evaluation system. During prequalification, Highwire collects each contractor’s OSHA 300A logs for the past three years to compute average TRIR and DART rates, quantifying both overall recordable injuries and more serious cases involving lost or restricted days. These three-year averages are benchmarked against the latest Bureau of Labor Statistics industry rates for the contractor’s trade, ensuring performance is judged relative to peers rather than in isolation.

In Highwire’s scoring model, a contractor with incident rates well below industry norms earns the maximum safety points in these categories (for example, a DART rate under 60% of the industry average yields full credit) while an abnormally high rate (over 200% of the norm) results in zero points. Together, the TRIR and DART metrics form a substantial portion of the overall Highwire Safety Score (part of the 55% weight allocated to lagging indicators of past performance), providing a quantitative baseline of a contractor’s safety record.

The Highwire platform incorporates TRIR and DART seamlessly into its dashboards and analytics to support data-driven safety decisions. Contractors and clients can view a transparent breakdown of how these metrics influence the 0–100 Safety Score on the Highwire dashboard, which highlights the specific factors contributing to the score and flags safety strengths or weaknesses in the contractor’s profile.

A Trending Safety Analysis graph further visualizes each contractor’s recordable incident rate (TRIR) and DART rate over time alongside their Safety Score, complete with peer benchmarks for context. This integrated approach allows project owners and safety managers to quickly identify if a contractor’s incident rates deviate from industry expectations and to factor those insights into prequalification or risk mitigation strategies.

Notably, Highwire treats TRIR and DART as important inputs rather than stand-alone verdicts. The platform balances these lagging metrics with in-depth evaluations of safety programs, management systems, and other leading indicators, ensuring that contractor assessments account for both past performance and the proactive measures in place to prevent future incidents.