OSHA porta potty requirements for a construction site: how many toilets per worker?

OSHA 29 CFR 1926.51(c) sets the minimum number of toilets required on a construction site. For 1 to 20 workers, you need one standard portable toilet. For 21 to 199 workers, you need one toilet seat and one urinal per 40 workers. For 200 or more workers, you need one toilet seat and one urinal per 50 workers. Mobile crews with immediate access to nearby facilities are exempt.

The count is for the peak crew size. Your site will grow to 60 workers. The OSHA rule requires two toilet seats and two urinals for that number. Many companies meet this with two standard units and one portable urinal, or three standard units. A deluxe portable toilet with a flushing bowl and sink can replace a standard unit and a handwash station.

An ADA-compliant unit is required by the ADA cluster rule. If you cluster multiple units at one location, at least 5 percent (but at least one) must be an ADA-compliant portable toilet. For a cluster of three units, one must be ADA-compliant. This unit provides the required wheelchair turning space.

Placement and service matter for compliance. The units must be serviced to be sanitary. Weekly service visits are standard. Place them on level ground with clear truck access for the vacuum truck. Blocked access results in a missed service.

For a crew of 60 working a standard week without alcohol or food service, three standard units or two standard units plus one urinal meets the OSHA minimum. Add an ADA unit if they are clustered. That's the baseline your safety officer is asking for. Does your site have any tricky access or long-term plans that change the math?