How Many Porta Potties Per Person Does OSHA Require?

OSHA requires at least one toilet on any construction site with 20 or fewer workers, one toilet seat and one urinal for every 40 workers on crews of 20 to 199, and one toilet seat and one urinal for every 50 workers once the crew hits 200 or more. That is the short answer to how many porta potties per person OSHA requires, and it comes straight from Table D-1 in the construction sanitation standard at 29 CFR 1926.51.

OSHA Toilet Ratios by Crew Size

Table D-1 in 29 CFR 1926.51(c)(1) sets three tiers:

20 or fewer employees: at least one toilet facility.
20 to 199 employees: one toilet seat and one urinal per 40 workers.
200 or more employees: one toilet seat and one urinal per 50 workers.

Worked out, a crew of 80 needs at least two toilet seats and two urinals. A crew of 250 needs five of each. When the math produces a fraction, round up. These figures are the legal floor, not a recommendation, and the ratio assumes steady use spread evenly through the day. Real sites see spikes at shift change and lunch, so many site managers add units above the minimum to keep lines from forming.¹

The standard also addresses genuinely remote or temporary field conditions where a standard portable toilet cannot be delivered. Even then, at least one toilet facility must be available. “Temporary field conditions” is not a pass; it obligates the employer to find an alternative, which can mean arranging quick transportation to the nearest restroom.¹

Counting the Right Number of Workers

Crew sizes on construction sites move around every week as trades cycle in and out. The unit count has to match the actual headcount on any given day, not last month’s plan and not the project average. If your framers finish and 15 electricians move in behind 60 laborers, your peak headcount is what OSHA measures against, not the number you had when you priced the porta potty contract.

Tracking daily sign-ins against your unit count is the cleanest way to stay ahead of an inspector doing the same math. It also gives you a record to show that you scaled up when the crew grew.

Placement and Access

Having enough units on paper is not enough if workers cannot reach them quickly. OSHA requires prompt access and expects employers to let workers leave their work area to use the restroom as needed. For mobile crews without toilets right at the work location, OSHA expects transportation that gets a worker to a restroom in under 10 minutes.²

Rules that effectively discourage restroom use are not allowed. Sign-out procedures or requiring a supervisor’s approval are permissible only if they do not create extended delays. OSHA notes that restroom needs vary based on medication, fluid intake, temperature, and individual health, so policies that limit breaks to fixed intervals will not hold up.²

On large or multi-story projects, this practical access requirement usually means positioning units on multiple floors or at several access points, not clustering them all near the site entrance.

When a Unit Does Not Count Toward the Minimum

A toilet that is overflowing or out of supplies does not count toward your required minimum. OSHA has confirmed in interpretation letters that construction site toilets must be maintained in sanitary condition, and a unit that fails that standard is treated the same as no unit at all for compliance purposes.³

The regulation itself does not spell out an exact servicing schedule, but OSHA references ANSI Z4.3 as a benchmark. That standard calls for a portable toilet used by up to 10 workers to be serviced, meaning the waste tank emptied and the interior cleaned, at least once per week. Heavier use means more frequent service. Running extra units above the minimum can stretch the interval a bit, but letting any single unit deteriorate to unusable puts you out of compliance the moment an inspector sees it.³

Maintenance also covers stocking toilet paper and keeping doors, locks, and ventilation openings working. A servicing log with dates, unit numbers, and the vendor’s name is often the difference between a warning and a formal citation.

Accessible Units: The Construction Exemption

The ADA Standards for Accessible Design generally require at least 5% of single-user portable toilets in each cluster to be wheelchair-accessible, with a minimum of one accessible unit. Portable toilets provided on construction sites specifically for construction workers are fully exempt from that requirement.⁴

The exemption only covers units used by construction personnel. If members of the public, office staff, or other non-construction employees use the same facilities, the 5% rule applies to those units. A site with a sales office or model home that visitors enter needs ADA-compliant visitor restrooms even if the crew’s units are exempt.

Penalties for Getting the Count Wrong

OSHA treats most sanitation shortfalls as serious violations, with a penalty of up to $16,550 per violation as of 2026 and a minimum of $1,085. Each deficiency stands on its own, so missing toilets, missing handwashing stations, and unsanitary conditions can each be a separate citation from the same inspection.⁵

Willful violations, where the employer knew the requirement and consciously ignored it, top out at $165,514 per violation with a minimum of $11,823. Repeated violations, where OSHA has cited the same employer for the same issue before, carry a minimum of $4,256 and the same $165,514 ceiling. One inspection at a site with several previously flagged sanitation problems can generate six-figure exposure.⁵

Failure-to-abate penalties are their own category. If OSHA issues a citation and the employer misses the abatement deadline, the agency can assess up to $16,550 per day the violation continues, generally capped at 30 days. On a fix as simple as calling the vendor for another unit, that daily meter is expensive.⁵

1
eCFR. 29 CFR 1926.51 – Sanitation
2
Occupational Safety and Health Administration. Restrooms and Sanitation Requirements
3
Occupational Safety and Health Administration. Whether Toilets at a Construction Jobsite Must Be in a Sanitary Condition to Meet the Requirements of 29 CFR 1926.51(c)
4
United States Access Board. Chapter 6 – Toilet Rooms
5
Occupational Safety and Health Administration. 2026 Annual Adjustments to OSHA Civil Penalties