Published 2026-03-19 · Methodology
PlainSafetyScore assigns letter grades (A through F) to employers based on their workplace injury rates relative to their industry. Here's exactly how we do it.
Data Sources
OSHA Injury Tracking Application (ITA): Federal law requires establishments with 20+ employees in high-hazard industries (and 250+ employees in all industries) to electronically submit their OSHA 300A summary data annually. We use 2016-2024 data.
BLS IIF Benchmarks: The Bureau of Labor Statistics publishes industry-average injury rates annually through its Survey of Occupational Injuries and Illnesses (SOII). We use 2-digit NAICS sector averages as benchmarks.
The Grading Formula
Each employer's average TCR (across all reported years) is compared to their industry's BLS benchmark:
- Grade A: Average TCR ≤ 50% of industry benchmark - significantly safer than average
- Grade B: Average TCR 50-80% of benchmark - better than average
- Grade C: Average TCR 80-120% of benchmark - at or near industry average
- Grade D: Average TCR 120-200% of benchmark - worse than average
- Grade F: Average TCR > 200% of benchmark - more than twice the industry average
Average employer TCR as a share of the BLS industry benchmark
A Grade A establishment runs at half its industry's injury rate or less; a Grade F runs at more than double. The benchmark is industry-specific, so a C in healthcare and a C in finance reflect very different absolute injury rates.
Why Average TCR (Not Latest Year)?
A single year can be misleading. A one-time spike might reflect an unusual event. We average across all reported years to give a more stable picture of the employer's safety culture. We show year-by-year data on each employer page so you can judge the trend yourself.
Eligibility Criteria
To receive a grade, an employer must have:
- 2+ years of reported data (reduces noise from single-year anomalies)
- Meaningful establishment size (roughly 20+ average employees, or 40,000+ annual hours)
- Valid hours-worked data for TCR calculation
Industry Benchmark Methodology
We match each employer to a BLS industry benchmark using their primary NAICS code. BLS publishes injury rate averages for each 2-digit NAICS sector annually. These benchmarks capture the inherent risk level of different types of work, construction and manufacturing have naturally higher injury rates than professional services, so comparing employers within their own sector ensures fair grading.
For employers whose NAICS code maps to multiple BLS categories, we use the most specific available benchmark. If only a broad sector benchmark is available, we use that. The benchmark year is matched to the OSHA reporting year to ensure contemporaneous comparison. BLS benchmarks are updated annually, so the standard against which each employer is measured reflects current industry conditions.
It is important to note that BLS benchmarks represent national averages. Regional variation in injury rates exists due to differences in climate, workforce demographics, and state-level regulation. An employer in a state with more stringent safety enforcement may face a higher effective bar than the national benchmark suggests.
Multi-Establishment Employers
Large companies often have multiple establishments (physical locations) reporting separately to OSHA. Each establishment receives its own grade based on its own injury data. This means a single company can have Grade A locations and Grade F locations simultaneously. We grade at the establishment level because safety conditions are inherently local, corporate policies matter, but execution varies by site.
When searching for a large employer, look for the specific location where you work or are considering employment. The corporate headquarters grade may differ significantly from a field office, warehouse, or manufacturing plant operated by the same company.
Limitations
OSHA ITA data reflects reported injuries - underreporting is a known issue. Some research suggests actual injury rates are 2-3x reported rates in some industries. An employer's grade reflects their compliance with reporting as much as their actual safety. An employer with Grade A may have excellent safety, or may have poor reporting practices.
How to Use the Grades
Use grades as a starting point for research, not a definitive verdict. A Grade D or F employer warrants closer investigation - check the establishment’s OSHA enforcement history on the OSHA inspection search, read employee reviews, and ask questions during job interviews.
Comparing Grades Across Industries
It is essential to compare employers within the same industry rather than across industries. A Grade C in healthcare (where the baseline injury rate is high) and a Grade C in finance (where the baseline is very low) represent fundamentally different absolute levels of risk. The grading system accounts for this by using industry-specific benchmarks, but users should understand that all grades are relative measures, not absolute safety indicators.
When evaluating potential employers, check both the letter grade and the raw TCR value. Two Grade B employers in different industries may have dramatically different actual injury rates. The grade tells you how the employer compares to peers; the raw rate tells you the absolute likelihood of experiencing a workplace injury at that establishment.
If you are comparing job offers across industries, say, a warehouse position versus a retail position, looking at the raw TCR for each specific employer gives a more meaningful comparison than comparing letter grades alone.
PlainSafetyScore grades are based on publicly available government data. They are not safety certifications or endorsements. Always verify current conditions directly with the employer or OSHA.