composting chamber. Composting toilets can be used to implement an ecological sanitation approach for resource recovery, and some people call their composting toilet designs "ecosan toilets" for that reason. However, this is not recommended as the two terms (i.e. composting and ecosan) are not identical. Composting toilets have also been called "sawdust toilets", which can be appropriate if the amount of aerobic composting taking place in the toilet's container is very limited. The "Clivus multrum" is a type of composting toilet which has a large composting chamber below the toilet seat and also receives undigested organic material to increase the carbon to nitrogen ratio. Alternatives with smaller composting chambers are called "self-contained composting toilets" since the composting chamber is part of the toilet unit itself. Applications Composting toilets can be suitable in areas such as a rural area or a park that lacks a suitable water supply, sewers and sewage treatment. They can also help increase the resilience of existing sanitation systems in the face of possible natural disasters such as climate change, earthquakes or tsunami. Composting toilets can reduce or perhaps eliminate the need for a septic tank system to reduce environmental footprint (particularly when used in conjunction with an on-site greywater treatment system). These types of toilets can be used for resource recovery by reusing sanitized feces and urine as fertilizer and soil conditioner for gardening or ornamental activities. Basics Components and use A composting toilet consists of two elements: a place to sit or squat and a collection/composting unit. The composting unit consists of four main parts: storage or composting chamber a ventilation unit to ensure that the degradation process in the toilet is predominantly aerobic and to vent odorous gases a leachate collection or urine diversion system to remove excess liquid an access door for extracting the compost Many composting toilets collect urine in the same chamber as feces, thus they do not divert urine. Adding small amounts of water that is used for anal cleansing is no problem for the composting toilet to handle. Some composting toilets divert urine (and water used for anal washing) to prevent the creation of anaerobic conditions that can result from over saturation of the compost, which leads to odors and vector problems. This usually requires all users to use the toilet in a seated position. Offering a waterless urinal in addition to the toilet can help keep excess amounts