How Many Porta Potties Do I Need?
One planner for events, builds, oilfield locations and farm crews, plus the charts and rules behind every number.
How do I size an event?
Size an event at 1 standard unit per 50 guests for up to 4 hours. Add 1 unit for every 4 when it runs longer, add about 15% for drinks, and make at least 5% of units accessible for public events. Plan 1 handwash station per 10 toilets. For 500+ people, use the PSAI chart below.
What's the rental for?
How big is it?
What's the site like?
On the South Plains, wind and freezes change how we set a unit, not how many you need.
Check your gate width with the gate fit checker before we roll a truck.
Events: 1 unit per 50 guests for up to 4 hrs, +1 per 4 for longer events, PSAI chart for 500+, +15% with drinks, at least 5% accessible. Crews: OSHA 1926.51, 1910.141 or 1928.110 minimums vs. PSAI's 1 unit per 10 workers. Full method.
What does the PSAI chart say for big crowds?
The PSAI chart says 1,000 people need 8 units for 4 hours, 2,000 people need 16 for 6 hours, 5,000 need 50 for 8 hours, and 10,000 need 100 for 8 hours. The chart assumes no pumping during the event, which is why multi-day events add overnight services.
| People | 2 hrs | 4 hrs | 6 hrs | 8 hrs | 10 hrs |
|---|---|---|---|---|---|
| 500 | 4 | 5 | 7 | 9 | 12 |
| 1,000 | 6 | 8 | 9 | 12 | 13 |
| 2,000 | 6 | 12 | 16 | 20 | 25 |
| 5,000 | 15 | 25 | 38 | 50 | 63 |
| 10,000 | 25 | 50 | 75 | 100 | 125 |
| 20,000 | 50 | 100 | 150 | 200 | 250 |
How many for a crew?
Crews follow three OSHA tables. Construction (1926.51) needs 1 toilet for 20 or fewer workers. General industry, including oilfield locations (1910.141), needs 1 for 1–15, 2 for 16–35 and 3 for 36–55. Farm crews of 11 or more (1928.110) need 1 toilet and 1 handwash station per 20. We plan 1 unit per 10 workers.
| Workers | Construction 1926.51 | Oilfield 1910.141 | Farm 1928.110 |
|---|---|---|---|
| 10 | 1 | 1 | Not required (under 11) |
| 20 | 1 | 2 | 1 + 1 handwash |
| 40 | 1 seat + 1 urinal | 3 | 2 + 2 handwash |
| 80 | 2 seats + 2 urinals | 4 | 4 + 4 handwash |
Sources: OSHA 1926.51 · OSHA 1910.141 · OSHA 1928.110.
Written by the Scott Rental Works dispatch team: the people who schedule, deliver, service and pick up our units from 2201 34th St in Lubbock.
We checked these facts against OSHA, the International Plumbing Code, the 2010 ADA Standards, PSAI guidance, manufacturer spec sheets, NWS Lubbock climate normals and City of Lubbock pages. Last reviewed .
Related questions
Every question below was asked on a real rental call. The short answer comes first, then the conditions that change it.
How many people per porta potty?
Plan 1 standard unit per 50 guests for an event up to 4 hours. PSAI rates a unit at about 200 uses between services. Longer events, alcohol and mostly female crowds need more units or a mid-event service.
Do I need an ADA unit?
For public events, plan at least 5% of the units in each cluster as accessible, and never fewer than one. Private parties need one only if a guest uses a wheelchair or walker. If an inspector will check, rent the ADA-compliant model with paperwork.
Do I need a handwashing station?
Add one whenever food is served, at petting zoos, and on jobsites where crews handle paint, coatings or chemicals. Plan 1 station per 10 toilets. Deluxe units have their own sink, which covers small parties.
How many toilets for my crew?
OSHA 29 CFR 1926.51 requires 1 toilet for 20 or fewer workers, then 1 seat and 1 urinal per 40 workers up to 199. We recommend 1 unit per 10 workers on a 40-hour week with weekly service, which keeps lines and odor down.
What are the rules for an oilfield location?
OSHA says drilling and servicing fall under general industry, 29 CFR 1910.141. That means 1 toilet for 1–15 employees, 2 for 16–35, 3 for 36–55, and up from there. Mobile crews with quick transport to facilities are exempt. Site prep and pad building count as construction.
Do harvest crews need toilets?
Yes, on farms with 11 or more hand laborers. OSHA 1928.110 requires 1 toilet and 1 handwashing facility per 20 workers, within a quarter-mile walk, unless crews are in the field 3 hours or less. Towable units move with the crew.
Get an itemized quote
Six fields. You get one line each for the unit, dates, delivery, pickup, servicing and fees. If we can't hit your date, we'll tell you on the first call so you aren't left waiting for a callback.
- Free cancellation up to 24 hours before drop-off
- Weather call? We move your date, no charge
- Delivered pumped, sanitized and stocked