- OSHA 29 CFR 1926.51(c) requires at least 1 toilet for 20 or fewer construction workers.
- Sites with 20 or more workers need 1 toilet seat and 1 urinal per 40 workers; 200 or more need 1 of each per 50.
- Farm field work under 29 CFR 1928.110 needs 1 toilet and 1 handwashing facility per 20 workers, within a 1/4-mile walk.
- Alabama is 1 of the states with no OSHA-approved State Plan, so federal OSHA covers most private employers there.
- Our recommendation goes beyond the minimum: about 1 standard unit per 10 workers, with weekly service.
OSHA portable toilet requirements for construction sites come from 29 CFR 1926.51(c), Table D-1. A site with 20 or fewer workers needs at least 1 toilet, and larger crews need 1 toilet seat and 1 urinal per 40 workers, or per 50 once you pass 200. Alabama follows these federal rules for most private employers.
This guide is general information, not legal advice. Confirm your site's needs with your safety officer.
What does OSHA Table D-1 require on a construction site?
OSHA Table D-1 in 29 CFR 1926.51(c) sets the minimum number of toilets on a construction site. A crew of 20 or fewer needs at least 1 toilet. A crew of 20 or more needs 1 toilet seat and 1 urinal per 40 workers, and a crew of 200 or more needs 1 seat and 1 urinal per 50 workers.
| Number of employees | Minimum facilities (Table D-1) |
|---|---|
| 20 or fewer | 1 toilet |
| 20 or more | 1 toilet seat and 1 urinal per 40 workers |
| 200 or more | 1 toilet seat and 1 urinal per 50 workers |
You can read the full text on the eCFR page for 29 CFR 1926.51. The rule also says that under temporary field conditions, at least 1 toilet facility must be available. Sites without a sewer may use chemical toilets, which is what a porta potty is.
Are there exceptions to the toilet rule?
The main exception to the OSHA toilet rule covers mobile crews. Section 1926.51(c) does not apply to mobile crews that have transportation readily available to nearby toilet facilities. A road crew that moves all day with a truck may qualify, but a crew working one fixed site for days or weeks usually does not.
Local codes can also limit what kind of toilet is allowed. Ask your safety officer if your crew counts as mobile before you skip a unit.
Does OSHA require handwashing on job sites?
OSHA requires handwashing facilities on job sites under 29 CFR 1926.51(f). Lavatories must be available at all places of employment, with soap, towels or air dryers, and running water. Workers using paint, coatings, herbicides, or other harmful contaminants need washing facilities near the work, though mobile crews with nearby facilities are exempt.
A standard porta potty has hand sanitizer but no sink. If your crew handles concrete, paint, or chemicals, add a hand washing station rental with soap, fresh water, and towels. Ask your safety officer if your setup meets the lavatory rule.
What are the rules for farm field work?
Farm field work follows 29 CFR 1928.110, not the construction rule. When 11 or more workers do hand labor in the field, the employer must provide 1 toilet and 1 handwashing facility for every 20 workers or fraction of 20. The facilities must sit within a one-quarter-mile walk of each worker.
- Work of 3 hours or less per day, including travel time, does not require facilities.
- Where terrain makes the quarter-mile rule impossible, facilities go at the closest point a vehicle can reach.
- Example: 35 field workers need 2 toilets and 2 handwashing facilities, since 35 is one full 20 plus a fraction.
Read the full rule on the eCFR page for 29 CFR 1928.110.
Does Alabama have its own OSHA rules?
Alabama does not have an OSHA-approved State Plan. Federal OSHA covers most private employers in Alabama, so Table D-1 applies on private construction sites, while state and local government workers fall outside federal OSHA. City or county rules may add their own sanitation needs, so check locally too.
You can confirm this on OSHA's State Plans page. Neighboring Georgia also has no State Plan for private employers, which matters for crews working near Rome, GA.
What is the legal minimum versus what we recommend?
The legal minimum and a good working setup are not the same. OSHA's minimum lets 1 toilet serve up to 20 workers. Our recommendation is about 1 standard unit per 10 workers with weekly service, a ratio that keeps lines short at breaks, keeps tanks from filling before service day, and keeps crews on site.
A standard unit has both a seat and a urinal. Many contractors count it as 1 seat plus 1 urinal, but confirm that with your safety officer. Here is the math, rounded up to whole units.
| Workers | OSHA minimum | How the math works | Our recommendation |
|---|---|---|---|
| 8 | 1 toilet | 20 or fewer = 1 | 1 standard unit, weekly service |
| 25 | 1 seat + 1 urinal | 25 ÷ 40 = 0.6, round up to 1 | 3 standard units (25 ÷ 10 = 2.5, round up) |
| 60 | 2 seats + 2 urinals | 60 ÷ 40 = 1.5, round up to 2 | 6 standard units |
| 220 | 5 seats + 5 urinals | 220 ÷ 50 = 4.4, round up to 5 | 22 standard units |
For long jobs, see our construction porta potty rental page, which covers 28-day billing and weekly service. Our guide to porta potty servicing explains when big crews need extra visits. For other crew sizes, use how many porta potties do I need.
Need units now? Call (256) 540-7374 by 12 PM Mon–Sat for same-day delivery, or request a quote.