The OSHA table
| Number of employees | Minimum facilities (29 CFR 1926.51, 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 |
Most standard portable toilets include both a seat and a urinal, so one unit typically counts toward both.
Minimum vs. what crews actually need
The OSHA table is a floor. Most contractors plan more units so crews aren't waiting in line, particularly on long shifts. The common industry guideline is one unit per ten workers per 40-hour week with weekly service.
| Workers | OSHA minimum | Recommended (40 hrs/week) | Recommended (50 hrs/week) |
|---|---|---|---|
| 5 | 1 | 1 | 1 |
| 10 | 1 | 1 | 2 |
| 20 | 1 | 2 | 3 |
| 30 | 1 | 3 | 4 |
| 50 | 2 | 5 | 7 |
| 75 | 2 | 8 | 10 |
| 100 | 3 | 10 | 13 |
Handwashing requirements
Under 29 CFR 1926.51(f), employers must provide adequate washing facilities for employees applying paints, coatings, herbicides or insecticides, or doing other work where contaminants may be harmful. Facilities must be near the worksite and equipped for workers to remove the contaminants. Many contractors simply add a handwashing station to every site.
Mobile crews
The requirement doesn't apply to mobile crews that have transportation readily available to nearby toilet facilities. Road crews and short-duration jobs often fall under this exception; fixed job sites generally don't.
This guide summarizes the federal standard for general information. Check current OSHA regulations and any state, local or contract requirements for your project.
Frequently asked questions
How many porta potties does OSHA require per worker?
One toilet for 20 or fewer workers, one toilet seat and one urinal per 40 workers for 20 or more, and one seat and one urinal per 50 workers for 200 or more (29 CFR 1926.51).
Does OSHA say how often portable toilets must be cleaned?
OSHA requires sanitation facilities to be maintained in a sanitary condition. Weekly service is the industry standard for a typical crew, with more frequent service for heavy use.
Are handwashing stations required on construction sites?
OSHA requires washing facilities for workers applying paints, coatings, herbicides or insecticides, or doing other work where contaminants may be harmful.