The OSHA table
Under 29 CFR 1926.51(c)(1), toilets must be provided for employees according to this table:
| Number of employees | Minimum number of facilities |
|---|---|
| 20 or fewer | 1 |
| 20 or more | 1 toilet seat and 1 urinal per 40 workers |
| 200 or more | 1 toilet seat and 1 urinal per 50 workers |
Source: OSHA 29 CFR 1926.51(c). This is general information, not legal advice. Confirm current requirements with OSHA or ADOSH.
Examples
| Crew size | Minimum | What we'd suggest in a Phoenix summer |
|---|---|---|
| 8 workers | 1 toilet | 1 unit, weekly service |
| 20 workers | 1 toilet | 2 units, or 1 with extra service |
| 60 workers | 2 seats + 2 urinals | Units spread across the site, plus handwashing |
Other requirements to know
Mobile crews
The toilet requirements don't apply to mobile crews that have transportation readily available to nearby toilet facilities, such as road crews moving between locations.
Where there's no sewer
Where no sanitary sewer is available, OSHA permits chemical toilets, recirculating toilets and other approved options. Portable toilets are the standard solution on most sites.
Washing facilities
OSHA 1926.51(f) requires adequate washing facilities for employees working with paints, coatings, herbicides, insecticides or other contaminants that can be harmful. That covers many trades. Portable handwashing stations meet this need on sites without running water.
Arizona: ADOSH
Arizona runs a state OSHA plan through the Arizona Division of Occupational Safety and Health (ADOSH), which covers most private employers in the state and generally follows the federal construction standards.
Why the minimum isn't enough in Phoenix
Heat safety guidance encourages workers to drink water frequently in hot weather, which means more restroom trips. A single toilet for a 20-person crew in July will fill quickly and become unpleasant, and workers avoid unpleasant restrooms by drinking less, which is a heat-illness risk. Add units or service visits in summer. See porta potties in Arizona summer.
Keep it simple
Tell us your crew size, shift length and project timeline. We'll recommend units, ADA and handwashing needs, and a service schedule. We'll deliver roll-off dumpsters for the same site too.
Set up compliant site restroomsCall with crew size and start date.
(602) 595-7860Common questions
How many porta potties does OSHA require per worker?
One toilet for 20 or fewer workers. For 20 or more, 1 toilet seat and 1 urinal per 40 workers. For 200 or more, 1 of each per 50 workers (29 CFR 1926.51).
Does OSHA require handwashing stations on construction sites?
OSHA requires adequate washing facilities where workers handle harmful contaminants such as paints and coatings (1926.51(f)). Many sites use portable handwashing stations for this.