Chemical toilet

A chemical toilet collects human excreta in a holding tank and uses chemicals to minimize odors. These toilets are usually, but not always, self-contained and movable. A chemical toilet is structured around a relatively small tank, which needs to be emptied frequently. It is not connected to a hole in the ground (like a pit latrine), nor to a septic tank, nor is it plumbed into a municipal system leading to a sewage treatment plant. When the tank is emptied, the contents are usually pumped into a sanitary sewer or directly to a treatment plant.

The portable toilets used on construction sites and at large gatherings such as music festivals are well-known types of chemical toilet. As they are usually used for short periods and because of their high prices, they are mostly rented rather than bought, often including servicing and cleaning.

Aircraft lavatories and passenger train toilets were in the past often designed as chemical toilets but are nowadays more likely to be vacuum toilets.

A simpler type of chemical toilet may be used in travel trailers (caravans) and on small boats.

Many chemical toilets use a blue dye in the bowl water. In the past, disinfection was generally carried out by mixing formaldehyde, bleach, or similar chemicals with the toilet water when flushed. Modern formulations are nitrate-based and work biologically.

Chemical toilets are a type of portable toilet and is also known by various tradenames, such as Port-a-John (American English), Portaloo (British English), or honey bucket. The last two are the names of companies and "Portaloo" is a British and European Community registered trade mark.

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