Sewage treatment plants or facilities · California
Delta Diablo
Antioch, CA · ~68 workers · 2 years of OSHA Injury Tracking Application data.
- F
- Failing Safety Record
- 4.2
- Avg TCR
- 1.2
- Industry avg
- 0
- Fatalities
The verdict
Delta Diablo runs at 348% of its industry's injury rate - far more dangerous than the typical Sewage treatment plants or facilities workplace, earning a grade F.
- F
- Failing Safety Record
- 4.2
- avg TCR · per 100 workers
- 1.2
- industry benchmark (BLS)
- 3
- recordable injuries tracked
Grade compares Delta Diablo's OSHA Total Case Rate of 4.2 to the Sewage treatment plants or facilities BLS benchmark of 1.2 (348% of benchmark) across 2 years of Form 300A filings (2016–2024). <a href="/methodology">See methodology</a> for reporting-limitation caveats.
Injury rate over time
Delta Diablo's yearly Total Case Rate, against the 1.2 industry benchmark.
Where Delta Diablo falls in its industry
443 Sewage treatment plants or fac establishmentsSafer than 47% of graded establishments in this industry, whose median TCR is 3.9.
Narrower to California alone (the establishments it most directly competes with for workers and contracts): ranked #29 safest of 78 Sewage treatment plants or fac employers in California.
Trend analysis for Delta Diablo
Between 2023 and 2024, Delta Diablo's Total Case Rate improved from 6.8 to 1.6 recordable injuries per 100 full-time workers, a 77% decrease across 1 year of OSHA reporting.
The safest year on record was 2024, at a TCR of 1.6, while 2023 saw the highest rate, at 6.8, a spread of 5.2 points between the best and worst reporting years. That's a wide swing relative to the establishment's overall rate, worth checking the year-by-year table below for whether a single severe year is driving the average, rather than a sustained trend.
Summed across those 2 reporting years, Delta Diablo recorded 3 total injuries and illnesses, with no fatalities reported in any of those years. Readers comparing establishments should weigh the 2-year trend above alongside establishment size, since a larger workforce naturally accumulates more raw incidents even at a lower per-100-worker rate.
Verify This Employer with OSHA
The 3 injuries, 2 illnesses shown on this page for Delta Diablo are sourced from its own 2 years of mandatory OSHA Form 300A summaries. Cross-check the underlying establishment record directly against the federal source, name, NAICS classification, recordable case totals, and inspection history are all searchable on OSHA's Establishment-Specific Injury and Illness Data system.
Verify on OSHA Establishment SearchSource: U.S. Department of Labor, OSHA Establishment-Specific Injury and Illness Data. NAICS 221320 - Sewage treatment plants or facilities.
DART Rate, Transparent Calculation (2024)
What is the DART rate formula?
DART (Days Away, Restricted, or Transferred) is computed by OSHA as incidents × 200,000 ÷ hours worked. The 200,000-hour denominator equals roughly 100 full-time workers, which lets establishments of very different sizes be compared directly.
1 DART incidents × 200,000 ÷ 127,501 hours worked = 1.57 DART
Methodology: 29 CFR 1904, OSHA Form 300A recordkeeping
Cross-Validating Context, Establishment vs Industry vs State
| Benchmark | TCR | Source |
|---|---|---|
| Delta Diablo (this establishment) | 4.17 | OSHA ITA Form 300A, 2-year avg |
| Collection, treatment, and disposal of waste through a sewer system industry avg | 1.20 | BLS IIF, NAICS 221320 |
| California state avg (all industries) | 5.64 | OSHA ITA, state-level rollup |
Industry benchmarks: Bureau of Labor Statistics, Injuries, Illnesses, and Fatalities (IIF) program
Reportable Incident Timeline
Year-by-year reportable incidents (recordable injuries + illnesses + fatalities) submitted by Delta Diablo to OSHA's Injury Tracking Application. Each row anchors to OSHA's inspection records search where you can pull the underlying inspection case numbers and citations for that establishment-year.
- 2024: 1 reportable incidents · 1 injuries, 0 illnesses, 0 fatalities - OSHA inspection records (case numbers)
- 2023: 4 reportable incidents · 2 injuries, 2 illnesses, 0 fatalities - OSHA inspection records (case numbers)
Source: OSHA Inspection Information System (IMIS) - inspection case-number records
Year-by-Year Safety Data
| Year | TCR | DART | Injuries | Illnesses | Fatalities |
|---|---|---|---|---|---|
| 2024 | 1.6 | 1.6 | 1 | 0 | 0 |
| 2023 | 6.8 | 1.7 | 2 | 2 | 0 |
What this grade means for you
Use this grade as a relative read on Delta Diablo's reported OSHA injury record versus its Sewage treatment plants or facilities peers, not a verdict on whether any single site is safe today.
- At 348% of the Sewage treatment plants or facilities benchmark, Delta Diablo reports more injuries than typical peers, ask specifically how the employer is reducing them. Know your rights
- Judge this record against the wider Sewage treatment plants or facilities sector, where injury rates vary widely, before comparing it in isolation. See the industry
- Grades reflect 2016–2024 filings; check the latest establishment record straight from OSHA, or look up a different employer. Look up another
Safety grades reflect employers' self-reported OSHA Form 300A filings from 2016 to 2024 and can lag current conditions. A grade is not a guarantee that any specific workplace is safe or unsafe today. See our methodology and disclaimer.
Frequently Asked Questions
What is Delta Diablo's safety grade?
How many injuries has Delta Diablo reported?
Similar Employers
Matched by safety record across the industry, by workforce size within California, and by nearby establishments in Antioch - a different peer set than the category browse links below.
Similar TCR (~4.2)
Similar size (~68 workers)
Read our methodology - how this data is sourced, computed, and verified.
Every figure and grade on PlainSafetyScore is computed directly from OSHA's published Injury Tracking Application data and BLS industry benchmarks, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these safety grades, or report a data error. Data current as of 2016-2024 OSHA ITA release.