What OSHA Says About Where, Not Just How Many
OSHA's construction sanitation rule, 29 CFR 1926.51, is mostly a count: one toilet for a crew of twenty or fewer, then a seat and a urinal per forty workers. But the rule only works if the toilet is somewhere the crew can get to. It exempts mobile crews, with the condition that transportation to a nearby toilet is readily available, and the exemption is the tell: OSHA assumes a fixed crew has a toilet within reach of where they're working, without a drive. On a rowhome lot that's obvious. On a six-acre site or a building going up twelve floors, it's the whole question.
The rule also says the toilet has to be kept sanitary, which means the service truck has to be able to reach it every week, and that hand washing has to be available. Put those together and the placement rule for a job site writes itself: the unit goes where the crew can walk to it in a minute or two, where the truck can get a hose to it, and where a hand wash station can stand beside it. Our How Many Porta Potties Do I Need guide covers the count; this one covers the spot.
Level, Firm and Reachable by the Truck
A portable restroom is a plastic cabin with a tank in the floor. Set on a slope, it rocks when the door swings and the tank sloshes toward the low side; set on soft fill, it sinks on the heavy corner over a wet week and leans. The spot should be level, or close enough that a couple of blocks under the low side fix it, and firm: packed gravel, asphalt, concrete, or ground that hasn't just been excavated. Wind matters too. An empty unit on an open lot in a March gust can go over, so on an exposed site it goes against a wall, a fence or a container, or gets staked.
Then think about the truck. Service means a vacuum truck parks nearby and runs a hose to the unit, pumps the tank, washes the unit and restocks it. The hose has a limited reach, so a unit tucked behind the building, up a flight of steps or at the far end of a lot the truck can't enter is a unit that can't be serviced from the street. The best spot is within a short hose run of a place the truck can legally stop, with nothing parked or stacked in the way on service day. Tell us where the truck can stop when you order and we'll set the unit to match.
Keep it away from the thing the crew is doing. A unit next to the saw station gets covered in dust; one in the swing of the excavator gets hit; one downhill of the concrete washout gets a slurry floor. Ten or fifteen feet off the work, on the way to the gate, is where people use it and nobody curses it.
On the Sidewalk or in the Street
Rowhome jobs often have no lot at all, so the unit has to go on the sidewalk or in a parking space, and that's city property. Philadelphia's Temporary No Parking permit, the one that puts a moving truck, a storage container or a dumpster in a parking lane, lists those three uses and not restrooms, so don't assume a parking-space permit covers a porta potty. Before you plan on the curb, ask the Streets Department's Right-of-Way Unit what it will allow at your address, and ask early, because a unit set on the public way without the city's say-so is the kind of thing a neighbor reports the same afternoon.
If the sidewalk is the spot, the sidewalk still has to work as a sidewalk. The ADA Standards call for a 36-inch continuous clear width on an accessible route, and a porta potty is about four feet deep; on a Philadelphia sidewalk that's often eight or nine feet wide with a tree pit and a stoop in it, that math gets tight fast. Set the unit at the building line with the door facing the street, keep the clear path on the curb side, and keep the hand wash station in line with the unit rather than beside it.
A unit in a parking lane is better for the sidewalk and worse for the neighbors, who lose a space on a block that never has enough. It also sits where a delivery truck can clip it. If it goes in the lane, put it hard against the curb at the end of the block or beside the dumpster, with the door facing the sidewalk, and plan on the service truck double-parking for a few minutes a week.
High-Rise Jobs: Units That Go Up on the Hoist
On a tower under construction, a toilet on the ground is a toilet nobody on the tenth floor uses. OSHA's reach assumption breaks down the moment a crew has to ride the hoist down and back, and the result is predictable and unpleasant. The answer is the high-rise unit: a narrow portable restroom, built to fit through a hoist door or a stairwell, with a smaller tank, that's set on the floor where the crew is working. As the building goes up, the units move up with it, every few floors, and the ground units stay for the trades at grade.
A high-rise unit's small tank fills in days, not a week, so it's paired with a holding tank on the floor: a sealed tank the unit drains into, pumped out on the service visit by a hose run up the building. That makes the service plan part of the placement plan. The units go near the hoist or the stair the service crew will use, not at the far end of the floor plate, and the holding tank sits where the hose can reach it. Tell us the floor count and the pour schedule and we'll lay it out with you before the first unit goes up.
On a mid-rise rehab, three or four stories with no hoist, the same idea applies at smaller scale: a unit on the ground, and a high-rise unit carried up a stairwell for the floors where the work is. The crew will tell you quickly whether the walk is too far.
Accessible Units and Where They Go
Construction sites are exempt from the ADA Standards' requirement for accessible portable toilets, but plenty of job sites have people who need one: an office trailer with staff and visitors, a site that's open to inspectors and clients, a renovation inside an occupied building. Where there's a reason, an accessible unit is wider, has grab bars and a level entry, and needs to sit on an accessible route: a path at least 36 inches wide, with a running slope no steeper than 1 in 20, from where people arrive to the unit's door. Gravel and a step up won't do; a paved path or a mat and a level pad will.
For an event, the accessible unit isn't optional. At least one in every cluster, and at least 5 percent of the total, on the same accessible route the guests use. It goes at the end of the row nearest the path, where a wheelchair can turn, not in the middle of the line.
Keeping the Block Happy
A porta potty on a Philadelphia block is a neighborhood issue before it's a job-site issue. The things that generate complaints are the obvious ones: a unit facing a neighbor's front window, a unit that's late on service in August, a unit that blows over, a unit left behind after the job is done. The fixes are just as plain. Face the door toward the work or the street, never toward a house. Keep the service on schedule and add a second weekly visit in the heat. Stake or wall the unit on a windy lot. And call for pickup the day the job wraps.
The service truck is the other thing the block notices. It needs to stop for a few minutes a week, and on a one-way street with no spare curb, that's a double-park. A unit set near the dumpster or at the end of the block, where the truck can pull to the curb, keeps the service visit from becoming the thing the neighbors remember about your job.
If you'd rather walk the site with someone, send the address and the start date through the quote form and tell us what the lot looks like. The Porta Potty Rental in Philadelphia page lists every unit, and contractors covers how we work with crews across a long job.
Related Pages
Sources
- OSHA 29 CFR 1926.51: Sanitation (Construction)
- U.S. Access Board: Guide to the ADA Standards, Toilet Rooms (Portable Units, §213.2)
- U.S. Access Board: Guide to the ADA Standards, Chapter 4: Accessible Routes
- City of Philadelphia: Apply for a Temporary No Parking (TNP) Permit (Moving Trucks, Storage Containers, Dumpsters)
This guide explains the rules in plain language; it isn't legal advice. Permit requirements can change, so confirm with the city before the box or the units go out.