How Many Toilets Does a Construction Site Need in Arizona?

Which rule applies to Arizona job sites?

For construction, Arizona adopts the federal rules. Arizona Administrative Code R20-5-601 requires each employer to comply with the federal construction standards in 29 CFR 1926, incorporated by reference, and applies them to construction work by both public and private employers across the state.

The sanitation section of that standard is 29 CFR 1926.51. It covers drinking water, toilets and washing facilities. Paragraph (c) is the part that sets how many toilets a construction site needs.

Projects in Maricopa County also fall under a county rule with its own ratio and a distance limit, covered in the next section.

What is Maricopa County's job-site rule?

Chapter II, Section VI, Regulation 5 of the Maricopa County Environmental Health Code says no person shall initiate or proceed with a construction, erection, alteration, repair, or razing project without first having provided "an adequate number of suitable sanitary toilets for the use of persons on the project in a ratio of at least one (1) toilet per twenty (20) persons." The toilets must be of the water-flushed or chemical type approved by the department and located on or within 200 feet of each work area within the project site.

Two details matter when planning. The county counts persons on the project, not only employees, and it sets a distance limit, so a large site with work areas far apart may need toilets in more than one place. The county text names alteration and repair projects, so remodels can be covered too; if you are not sure, ask Maricopa County Environmental Services.

The county rule applies to projects in Maricopa County. Some southeast Valley addresses are in Pinal County; for a project there, confirm Pinal County's requirements before you plan.

What does OSHA's toilet table require?

Section 1926.51(c)(1) ties the minimum number of toilet facilities to the number of employees on the site.

• 20 or fewer employees: at least one toilet facility.
• 20 or more employees: one toilet seat and one urinal per 40 workers.
• 200 or more employees: one toilet seat and one urinal per 50 workers.
• Temporary field conditions: under 1926.51(c)(2), provisions must still be made so that at least one toilet facility is available.

How do you count workers on a busy site?

OSHA's table counts employees, while the county rule counts every person on the project. Plan around the largest crew you expect on site at the same time, including subcontractors' crews, rather than an average day. Crew sizes usually change as a project moves through its phases, so revisit the count when the schedule changes.

Here is how the two rules work out for a few crew sizes. A crew of 15 needs at least one toilet under both. With 60 people on site, the county's one-toilet-per-20-persons rule works out to at least three toilets in total, placed so every work area has one on or within 200 feet; OSHA's table is counted separately in seats and urinals and gives two toilet seats and two urinals for 60 workers. Meet both. A crew of 250 falls in OSHA's 200-or-more tier at one seat and one urinal per 50 workers, five of each, while the county ratio works out to at least 13 toilets. Whoever is responsible for site safety should confirm the final count for the project.

Do toilets have to be kept clean to count?

Yes. In a 2006 interpretation letter, OSHA explained that a toilet is not provided under 1926.51(c)(1) if it is unsanitary, because unsanitary toilets are unusable and therefore not available. The letter also says the standard does not require toilets to be immaculate to be considered sanitary.

As one way to meet the obligation, OSHA pointed employers to the servicing schedule in the ANSI Z4.3 industry consensus standard, which calls for a toilet used by up to 10 people to be serviced at least once a week. OSHA's example: if 20 employees share one toilet, servicing it twice a week would likely keep it sanitary. In practice, more users per unit means more frequent servicing, so the servicing plan matters as much as the unit count.

When does OSHA not require toilets on site?

Under 1926.51(c)(4), OSHA's toilet requirements do not apply to mobile crews that have transportation readily available to nearby toilet facilities. OSHA has interpreted readily available as prompt access, and in a 2002 letter said that in general, toilets would be considered nearby if it would take less than 10 minutes to get to them.

That exception fits roving crews, such as a utility locate team moving between addresses. It does not fit a crew that works at one site all day, which needs facilities on the site. Maricopa County's rule has no mobile-crew exception in its text; for a project in the county, ask Maricopa County Environmental Services.

What about sites without a sewer connection or with hand-washing needs?

Many job sites have no sanitary sewer yet. Section 1926.51(c)(3) allows privies, chemical toilets, recirculating toilets or combustion toilets at those sites, unless local codes prohibit them. In Maricopa County, job toilets must be of the water-flushed or chemical type approved by the county.

Washing facilities are covered separately. Under 1926.51(f)(1), employers must provide adequate washing facilities for employees working with paints, coatings, herbicides, insecticides or other contaminants that could be harmful, close to the work and equipped so workers can remove those substances. Section 1926.51(f)(2) adds that washing facilities must be kept sanitary. The same standard, in paragraph (a), requires an adequate supply of potable drinking water at every place of employment.

What should you plan before ordering restrooms for a job site?

A few details up front make it easier to set up the right facilities and keep them usable for the whole project.

• The peak number of workers on site at once, and the dates that peak lasts.
• Where each work area is, so restrooms can sit on or within 200 feet of it.
• Start, finish and any shutdown dates, so delivery and pickup line up with the schedule.
• A level, stable placement that a service truck can reach, plus gate widths, turns and overhead clearance on the way in.
• Whether power and water are available near the placement, if you are considering a restroom trailer.
• Any washing needs for crews handling paints, coatings or other contaminants, and any accessibility needs for workers or visitors.

Common questions

Sources

• Maricopa County Environmental Health Code (Rev. 08/19/2026), Chapter II, Section VI (PDF)
• Maricopa County Environmental Services: Chemical toilets and portable restroom units FAQ
• OSHA: 29 CFR 1926.51, Sanitation (construction)
• OSHA interpretation (May 17, 2006): Toilets at a construction jobsite must be in a sanitary condition
• OSHA interpretation (June 7, 2002): Mobile crews must have prompt access to nearby toilet facilities
• Arizona Administrative Code R20-5-601: Federal construction standards adopted by reference