Event chart: guests and hours
| Guests | Up to 4 hrs | 6 hrs | 8 hrs |
|---|---|---|---|
| 50 | 1 | 2 | 2 |
| 100 | 2 | 3 | 4 |
| 150 | 3 | 4 | 5 |
| 200 | 4 | 6 | 7 |
| 300 | 6 | 8 | 10 |
| 500 | 10 | 13 | 16 |
| 750 | 15 | 20 | 24 |
| 1,000 | 20 | 26 | 32 |
Serving alcohol? Add about 15% to these numbers. Lots of children? Add a handwashing station near the units.
Construction chart: OSHA 1926.51
| Workers | OSHA minimum | Recommended |
|---|---|---|
| 1–20 | 1 toilet | 1 per 10 workers |
| 20–199 | 1 toilet + 1 urinal per 40 | 1 per 10 workers + handwashing |
| 200+ | 1 toilet + 1 urinal per 50 | Site plan with service schedule |
Weddings
Plan two to three flushable units or one two-stall restroom trailer for 100 guests, plus a handwashing station by the bar or food. See the wedding guide.
Accessibility and handwashing
Public events should include at least one ADA unit, with about 5% of all units accessible as a common rule. Add one handwashing station per three to four toilets.
Sizing questions
How many porta potties do I need for 100 guests?
Two units cover 100 guests for up to four hours. Plan three for six hours and four for eight hours or when alcohol is served.
How many porta potties for 200 people?
Four units for up to four hours, five to six for six hours and six to seven when alcohol is served or the event runs all day.
How many porta potties per worker does OSHA require?
OSHA 29 CFR 1926.51 requires at least one toilet for 20 or fewer workers, and one toilet plus one urinal per 40 workers for crews of 20 to 199.
Do I need a separate unit for women?
For large events, adding about 20% more units, or a few units reserved for women, shortens lines. Flushable units and trailers are popular near the main gathering.
How many handwashing stations do I need?
One station per three to four toilets, plus one near any food service or animal area.