After studying the situation in slums around the world, UN-HABITAT sought to devise a system that would replace manual pit latrine and septic tank emptying. It commissioned a mechanical system that would be capable of being manufactured locally using readily available components, that would be affordable, easily serviceable, able to operate in narrow passageways where other conventional exhauster vehicles cannot pass, and capable of sucking out dense waste sludge for transportation to a larger tanker vehicle. At the same time it was imperative that excrement be removed as safely as possible without posing further health hazards in slums. Thus in 1995 Manus Coffey and Associates Ltd (MCA) and UN-HABITAT designed and built the first prototype in Ireland: the MK I UN-HABITAT Vacutug.
http://www.un-habitat.org/categories.asp?catid=548
[Accessed: 04.01.2011]