Julia Rutherford Silvers, CSEP

Certified Special Events Professional

Event Management Authority

Like angels and elephants dancing on the head of a pin, our dreams and responsibilities may have no limits, but must be balanced according to the music of the moment.









Toilet Facilities

1 January 2010

Something to do

Something to see

Something to eat and drink

Somewhere to pee

Reprinted with permission from Risk Management for Meetings and Events (Butterworth-Heinemann, 2008)


As my little poem above illustrates, toilets will be needed for virtually every event. The event organizer will need to determine if there are sufficient toilet facilities at a purpose-built facility such as a hotel or convention center, and will need to arrange for portable toilet facilities for an event held at a site that does not already have them on-site (or enough of them for the size of the crowd expected).


Do the Math?

There are no universal standards for how many toilets are required and the guidance varies (see below); mandatory requirements vary by jurisdiction (country, state, and/or municipality). The reason for this is because calculating the number of toilets needed for an event is a multi-faceted mathematical exercise. The factors in determining toilet demand include:


Number of people in attendance – This is the baseline for determining the number of toilets (and hand-wash stations) needed but here’s why the guidance can be so confusing… no one is providing comparable figures.

  • A news story in the Wall Street Journal on the Obama inauguration cited:

    • The US Army standard is 1 toilet per 25 males and 1 toilet per 17 females

    • The US Park Service recommends 1 toilet per 300 people

    • Portable Sanitation Association International recommended 1 toilet per 134 people

    • International Code Council requires 1 toilet per 40 people at nightclubs

  • The Health & Safety Executive in the UK specifies 1 toilet per 500 males and 1 urinal per 150 males; and 1 toilet per 100 females for an event of six hours or more (if the event is less than six hours, the number of persons per toilet increases approximately 15%).

  • The US and Australian manuals for safe and healthy mass gatherings specify that the baseline for an eight-hour gathering of 500 or less should be 1 toilet and 2 urinals for males and 6 toilets for females (the charts provided go up to 5,000 persons and percentages for events of fewer hours).

  • The Canadian manual gives as its guidance 3 toilets and 3 urinals for males and 9 toilets for females for 1,200 persons.

Ratio of men to women –It is a physical fact of nature that men typically can urinate faster than women due to the types of clothing they wear and the ability to do so standing up rather than sitting or squatting. Studies suggest it takes 25 to 40% longer for a woman to use toilet facilities, and often longer due to waiting lines for facilities that are gender-specific. Unless the demographics of the specific event audience suggests otherwise, guidance is based upon a presumption of a 50/50 ratio.


Designated toilets – When gender-neutral or unisex facilities are provided (e.g. portable toilet stalls with both a seat and a urinal) calculations can be adjusted accordingly. In the alternative, gender-specific toilet facilities could be re-designated to accommodate a higher ratio as appropriate (or as needed). Accessibility legislation often mandates a certain percentage (typically 5%) of the total number of toilets be handicap-accessible. Certain jurisdictions also require separate toilet facilities (and specific hand-washing capabilities) for food service personnel, as well as specific limitations with regard to proximity to food service outlets.


Duration of the event – The longer the event, the more often an individual will need to use the toilet facilities. People typically need to urinate every two to four hours; this, of course, varies depending on fluid consumption and other activities.


Agenda of the event – Many event schedules have components that cause uneven usage distribution such as seminar sessions at a conference, segments of a concert or theatrical production, half-time at a sports event, or after the signature finale of a celebration or festival. When these breaks in the action occur, a much higher percentage of the audience will make a beeline for the toilets than if the agenda was less structured.


Event site – Toilet facilities should be properly positioned so that demand is evenly distributed. Typically toilet facilities at entry or exit points incur the highest usage, as do locations adjacent to high demand attractions or along high-traffic routes. Make certain toilet locations are clearly marked on site maps and other on-site signage so that users can locate other facilities that may be under-utilized.


Weather (for outdoor events) – Extreme heat and extreme cold both cause dehydration, which causes the kidneys to flush out water through sweating and urination. However, cold weather prevents one from sweating so you urinate even more.


Availability of alcohol and caffeinated beverages – Most guidance specifies anywhere from 20 to 40% additional toilet facilities are needed if alcohol is served. This is because alcohol consumption causes dehydration. The same holds true for caffeinated beverages such as colas and coffee. You urinate more fluid than the amount of water in the beverage, which then causes you to thirst for more fluids… a cycle that increases toilet demand.


How do I find out what my event will need?

You can look at websites of portable toilet suppliers for toilet calculator charts as a start. You should work with the vendor you select for your specific event because they should be able to incorporate the regulations pertinent to that jurisdiction and their experience with the types of events similar to yours. Always confirm your plans with the local authorities (they will probably be asking you for this information in the permit process for conducting your event). And don’t assume that a purpose-built facility will have sufficient toilet facilities. Know your event and know your audience!


My point of view…

Being a female who has stood in line far too many times, my personal recommendation is that you allot at least twice as many toilets for women if they are gender-designated. I, and many women I know, have been known to commandeer the men’s toilet facilities if the lines are too long!



2001-2016, Julia Rutherford Silvers, CSEP. Albuquerque, NM, USA. All Rights Reserved.

Terms of Use & Disclaimer