Most PROs are keenly aware of OSHA and the laws that they monitor and enforce. ANSI is another organization with safety standards that are important for our industry, our companies and our customers.
Question: We are a relatively new portable restroom service company. We have heard the phrase “ANSI standards” several times. Could you explain what these are and how they affect our business?
Answer: This is an excellent question. These safety standards are specific to our industry and all PROs, regardless of years in the business, need to understand them.
Background
ANSI stands for the American National Standards Institute, and its mission is to establish voluntary safety guidelines and best practices for a variety of industries. This organization was originally established in 1918 as the American Engineering Standards Committee, and it adopted its current name in 1969.
OSHA stands for the Occupational Safety and Health Administration and was created in 1970 to ensure safe and healthy working conditions. OSHA’s safety standards are legally enforceable and can carry penalties, usually found as a result of onsite inspections.
ANSI relies on a large group of organizations, associations and industry experts to research, monitor and establish their voluntary standards. As a result of the in-depth and detailed work in establishing these practices and procedures, OSHA often adopts ANSI standards. Even if not officially adopted, OSHA can incorporate ANSI standards in their laws. It has often been mentioned that ANSI provides technical support for OSHA.
ANSI Standards for the Portable Sanitation Industry
There are two ANSI standards that PROs need to understand and implement as part of their company safety policies. These standards are:
Z4.3 (2025) – “Standard for Sanitation – Nonsewered Waste Disposal Systems at Places of Employment: Minimum Requirements”
Z4.4 (2025) – “American National Standard for Sanitation – Nonsewered Waste Disposal Systems: Use by the General Public – Minimum Requirements”
The Portable Sanitation Association International is the Accredited Standards Developer for these standards. In 2025, the updates and revisions made by the PSAI were approved by the ANSI board.
Here is a summary of each standard along with recommendations on how to use this information to benefit both your company and your customers.
ANSI Z4.3
The target market of this standard is places of employment or, to use our industry vernacular, “residential and commercial construction sites.” The highlights of this very thorough and descriptive 17-page document are summarized below.
The determination as to the number of units per site was verified and unchanged since the last PSAI review of this standard in 2015. However, as a result of COVID in 2020, additional recommendations were made in terms of hand-wash stations. The language is as follows:
“In places of employment, a minimum of one nonflushing toilet is required per 10 workers, and one hand-wash facility is required per 20 workers, provided that they are working no more than 400 cumulative hours and service occurs no less than once every seven days.”
A table is provided in the document that allows for quick access as to both the number of units and hand-wash stations required at a site based on the number of workers and cumulative hours worked. The chart also shows service frequency where additional weekly services can provide the same sanitary conditions using fewer units.
We highly suggest obtaining these charts from the source and using them as they are an excellent resource for a PRO’s administrative and sales staff to have on hand when communicating with customers about beginning new jobs or suggesting additional equipment due to an increase in the number of workers on the job site.
Toilets and hand-wash stations are to be no more than 10 minutes total travel time from where the workers are assigned to work.
ADA facilities must be provided if they are used by the general public or by any worker protected by the ADA.
Requirements for each type of equipment are then described in detail:
Portable toilet requirements:
- Units must be fabricated from nonabsorbent, watertight materials.
- Deodorizers must comply with federal, state and local provisions.
- At the time of service, the waste container must be completely drained and sanitized, then recharged with water and deodorizers before use.
- Safety Data Sheets for all chemicals and cleaners used must be available and provided by the route service technician upon request.
- Units and equipment must be placed on clear and flat terrain away from traffic and other hazards.
Hand-wash facility requirements:
- Water supplied to hand-wash stations must be potable when transferred to the freshwater compartment of the service vehicle. At the moment of transfer, the water becomes nonpotable and unsafe for consumption.
- The stations need to be labeled as “not for consumption.”
- Service includes completely draining the graywater compartment, refilling the freshwater compartment and restocking the hand soap and paper towels.
Nonsewered sanitation trailers:
This section was upgraded from the 2015 standards to include not only enclosed portable restrooms but also decontamination units, locker compartments, shower facilities, shower and restroom facilities, and laundry trailers.
- All trailers must meet Federal Motor Carrier Safety Standards.
- There are requirements for trailer steps, handrails and ramps.
- Depending on state laws, an ADA unit placed next to a trailer is sufficient but in other states, there must be ADA access to the trailer and ADA facilities inside.
This ANSI standard concludes with a statement on waste disposal — namely, all disposal must be done at approved facilities and meet all applicable federal, state and local laws.
As evidenced above, ANSI Z4.3 can serve as a cornerstone for your company’s safety and training programs. This standard also includes a library of relevant industry terms that are used in the standard and can be another resource for PROs to use in employee training sessions.
ANSI Z4.4
This standard addresses usage of portable sanitation by the general public in public environments. Once again, using our industry vernacular, ANSI Z4.4 covers “special events.”
The standards presented in ANSI Z4.3 form the foundation for this standard. In addition, “the minimum requirement for any public event where there is no sanitary sewer, septic tank or onsite sewage disposal facility is one unit and one hand-wash or hand-sanitizing station.”
As with ANSI Z4.3, this standard also contains extremely useful tables on the number of portable units and hand-wash stations required at public gatherings based on crowd size, duration of the event and whether alcohol is served.
A few of the more notable standards include:
- A requirement that portable sanitation equipment must either be placed near a light source at an event or have temporary lighting installed such that at dusk, safe access by users is available and to also deter vandalism.
- During cold weather, hand-wash stations must still be made available at public gatherings. The recommendation is that alcohol-based hand-sanitizing stations be used.
- Units with waste are not to be transported from the event. All equipment is to be pumped empty before returning to the PROs facilities.
- Any situation where more stringent sanitation standards apply than those found within these standards, the additional and/or more stringent requirements shall be met.
As with the previous standard, ANSI 4.4 includes the charts as to the number of units and hand-wash stations required at public gatherings.
Scenarios
A unique addition to this standard by the PSAI Industry Standards Committee is the inclusion of various scenarios to illustrate the provision of toilet and hand-washing facilities for circumstances of concentrated use. By reviewing these scenarios, one can better understand the practical application of these standards concerning public gatherings.
These scenarios are:
- Scenario A – Beach parking area
- Scenario B – Day hiking trail head / boat ramp
- Scenario C – Campground
- Scenario D – Multi-weekend fair
- Scenario E – Multi-day music festival with multiple stages
Another interesting requirement is that food handlers and workers in medical stations at events must have toilets and hand-wash facilities that meet ANSI 4.3 standards and are separate from the facilities provided for public use.
This document concludes with references to the minimum standards for equipment — units, hand-wash stations and trailers — and the standards for the proper disposal of wastewater as outlined in detail in ANSI Z4.3.
Final Thoughts
Both ANSI standards educate PROs on proper equipment selection, usage in the field (construction sites and special events) and safety requirements. This knowledge can be used to train employees and to incorporate into company policies. Further, these standards — particularly the charts that help to determine equipment required — can assist and educate customers while establishing your company as a qualified and dependable business partner.
