Maryland rules for restroom, shower and combination trailer rentals
What OSHA, the ADA, Maryland agencies and local permit offices expect when you put a temporary restroom or shower trailer on a site.
OSHA and MOSH toilet and shower rules
Maryland runs its own OSHA-approved state plan, called MOSH, run by the Division of Labor and Industry. It covers private-sector workplaces and has adopted the federal construction (Part 1926) and general industry (Part 1910) standards. Those standards set minimum toilet counts by crew size, require handwashing, and require showers only when a specific standard calls for them, such as lead. Construction sites without a sewer may use chemical, recirculating or combustion toilets. Showers, where required, need hot and cold water, soap and individual towels. Employers, not the rental company, are responsible for deciding how many units a crew needs.
- Construction, 1926.51(c): 20 or fewer workers need 1 toilet; 20 or more need 1 seat and 1 urinal per 40; 200 or more, per 50.
- General industry, 1910.141(c) Table J-1: 1-15 employees need 1 toilet, 16-35 need 2, 36-55 need 3, 56-80 need 4, 81-110 need 5.
- Showers are required only when another standard says so; then 1 shower per 10 employees of each sex showering in the same shift (1926.51(f)(4), 1910.141(d)(3)).
- Example trigger: the lead standard, 1926.62(i), requires showers where feasible for workers exposed above the lead permissible exposure limit.
- Lavatories need hot and cold or tepid running water, hand soap and towels or air blowers; mobile crews with nearby facilities are exempt (1926.51(f), 1910.141(d)).
- Maryland's own unique MOSH rules listed by OSHA include field sanitation for agriculture; no Maryland-specific construction toilet table was found.
ADA and accessible restroom trailers
The 2010 ADA Standards apply to temporary as well as permanent buildings and facilities (201.3). Portable toilet units used only by construction workers on a construction site are exempt from the accessibility scoping and the accessible-route rule (203.2). Units open to the public are not exempt. For clusters of single-user portable toilet or bathing units, the Standards allow only a fraction (5 percent) to be accessible, and those must carry the International Symbol of Accessibility. An accessible toilet or shower must meet the technical rules in chapters 3, 4 and 6, such as turning space, grab bars, door width and ramp slope. Whether a multi-stall trailer counts as a cluster of single-user units is not settled here.
- Requirement: ADA Standards apply to temporary and permanent buildings and facilities (201.3). Construction-crew-only portable toilets are exempt (203.2).
- Requirement: accessible portable units in a cluster must show the International Symbol of Accessibility (213.2 Exception 3, 703.7.2.1).
- Requirement, accessible toilet room: 60 inch turning circle (304.3.1); 32 inch clear door width (404.2.3); 30 by 48 inch floor space (305.3).
- Requirement, toilets: side grab bar 42 inches minimum, rear bar 36 inches minimum (604.5). Where showers exist, one must meet 608 (213.3.6).
- Requirement for ramps: running slope not steeper than 1:12, clear width at least 36 inches, maximum 30 inch rise per run (405.2, 405.5, 405.6).
- Recommendation: Access Board guide says at least 5 percent per cluster; ADA.gov text says no more than 5 percent. Offering more is prudent.
Sources: ada.gov, ada.gov, access-board.gov
Wastewater, hauling and gray water
Maryland's on-site sewage rules (COMAR 26.04.02) define a 'portable unit' to include a restroom mounted on a trailer. For portable units the owner or operator must keep a maintenance agreement, have the unit pumped by a licensed septage hauler where applicable, supply handwashing, and supply potable water with backflow protection. Septage must go to a facility licensed by the Maryland Department of the Environment (MDE), and hauler vehicles must be kept clean, lettered and open to inspection. A time limit applies to portable units in some cases. Gray water from showers is not specifically addressed in the text reviewed, so its handling should be confirmed with MDE and the county health department.
- COMAR 26.04.02.01 defines 'portable unit' to include a transportable sewage device such as a chemical toilet or a restroom mounted on a trailer.
- COMAR 26.04.02.08 requires a maintenance agreement, pumping by a licensed septage hauler 'if applicable', handwashing stations and potable water with backflow prevention.
- COMAR 26.04.02.08 says a portable unit may not be used beyond 3 days in a 60-day period without Approving Authority authorization; context needs confirming.
- COMAR 26.04.02.09 requires septage disposal in compliance with State and local rules at a facility licensed by MDE.
- Septage vehicles must be kept clean and sanitary, carry the hauler name and the words 'Sewage Only', and are subject to inspection (26.04.02.09).
Sources: regs.maryland.gov, regs.maryland.gov, regs.maryland.gov
Maryland Department of Health and local health departments
Food service rules (COMAR 10.15.03) are administered through local approving authorities, which issue and renew food service licenses. For temporary or special food service facilities, the rules require temporary toilets where permanent ones are not required, handwashing with soap and paper towels where there is no pressure water, and potable water. Regular food service facilities need enough toilets for their size and a handwashing sink next to every toilet room. The reviewed text did not set a stand-alone toilet-count table for general public events, so event organizers should ask the county health department which permit and number of units applies to their event.
- COMAR 10.15.03.28: the 'approving authority' issues and renews food service facility licenses under Health-General sections 21-309 and 21-310.
- COMAR 10.15.03.25: special and temporary food facilities must provide temporary toilets if permanent ones are not required, and keep them sanitary.
- Same section: without pressure water, a handwashing setup with warm water, soap and paper towels is required; mobile units need a handwashing sink.
- COMAR 10.15.03.18: toilet rooms must be enclosed, ventilated and stocked with tissue; handwashing sinks must sit next to every toilet room.
- Mobile food units must hold a valid license from their home county; a mobile reciprocity license exists for operating elsewhere within 90 miles.
Sources: regs.maryland.gov, regs.maryland.gov, regs.maryland.gov, regs.maryland.gov
Fire code and the State Fire Marshal
Maryland's State Fire Prevention Code is COMAR 29.06.01. Its stated purpose includes fire hazards from how buildings, structures, tents, lots and premises are used or occupied, and it incorporates the 2024 editions of NFPA 1 (Fire Code) and NFPA 101 (Life Safety Code) with Maryland amendments. It is enforced by the State Fire Marshal or a legally designated fire official of a county or municipality, and required permits come from the appropriate authority where the activity takes place. Baltimore City is generally outside this chapter. The specific rules for tents, generator fuel storage or trailer spacing were not reviewed, so customers should ask the local fire marshal.
- COMAR 29.06.01.02 says the State Fire Prevention Code covers hazards in the use or occupancy of buildings, structures, tents, lots and premises.
- The same section incorporates the 2024 editions of NFPA 1 and NFPA 101 with State amendments in .07, .08 and .09.
- Enforcement is by the State Fire Marshal, a legally designated county or municipal fire official, or appointed persons (29.06.01.04A).
- Permits are obtained from the State Fire Marshal or the appropriate authority in the county, city or town where the activity is located (29.06.01.04D).
- The chapter generally does not apply in Baltimore City, except for conditions listed in Public Safety Article, Title 6, Subtitle 4 (29.06.01.03).
Sources: regs.maryland.gov, regs.maryland.gov, regs.maryland.gov
Site rules: Critical Area, floodplain, generators
Placing a trailer near water can trigger extra review. Maryland's Chesapeake Bay Critical Area covers land within 1,000 feet beyond the landward boundary of state or private wetlands, and local governments generally must keep at least a 100-foot buffer from tidal waters and certain streams, with limited disturbance allowed. In nontidal waters, MDE requires a permit for work that changes a stream or affects the 100-year floodplain, with specific rules for temporary floodplain construction. For power, federal OSHA requires GFCI protection or an assured grounding program for temporary construction-site receptacles, with a limited exemption for small generators. Stormwater and county zoning rules were not reviewed.
- Critical Area: land and water within 1,000 feet beyond the landward boundaries of State or private wetlands (COMAR 27.01.01.01B(18)).
- Local jurisdictions must establish a buffer of at least 100 feet from mean high water, tidal wetlands and tributary streams, with limited disturbance (COMAR 27.01.09).
- COMAR 26.17.04.03: an MDE permit is needed for work that alters a nontidal stream or affects the 100-year frequency floodplain.
- COMAR 26.17.04.08 sets conditions for temporary construction in a floodplain, such as no fill within 25 feet of a stream bank top.
- OSHA 1926.404(b)(1): 120-volt, 15 and 20 amp construction-site outlets need GFCIs or an assured equipment grounding program; 2-wire generators up to 5 kW are exempt.
Sources: regs.maryland.gov, regs.maryland.gov, regs.maryland.gov, regs.maryland.gov, osha.gov
This guide is general information, not legal advice. Rules change and local permit rules vary by county and town, so confirm the details with the agency or office named for your site. Find your place on the Maryland service area pages or call (888) 385-5513.
Request your Maryland quote
Tell us the Maryland address, how many people and how long. We reply with the trailer, the stall count and the price.
Prefer to talk? Call (888) 385-5513, open 24 hours a day.
Short-Term & Long-Term Rentals and Leasing.