There is considerable national interest in the use of commercial microbially derived products for controlling the rate of accumulation of the contents of pit latrines. Manufacturers claim that some of these products can reduce accumulation rates, prevent the pit from ever filling up, or even result in decreases in pit contents volume. Prior to this research, there have been no scientific publications that have conclusively supported or refuted these claims. This project undertook to perform reproducible laboratory tests that would quantify the effect of commercial pit latrine additive products. Protocols were developed and tested on a range of different commercial products sold for their ability to control the rate of accumulation of pit latrine contents. The effect of commercial additives on mass loss from VIP sludge in 300 g honey jars was compared to mass loss from similar units subjected to no treatment and treatment with water. The purpose of these experiments was to separate and quantify the effect of microorganisms or enzymes originating from commercial pit latrine additives from the effect of natural processes within the pit latrine sludge (including digestion by microorganisms in the VIP sludge and dehydration) and the effects of other actions associated with treatment, such as the addition of water. Results indicated that insignificant mass loss occurred in all anaerobic test units, while significant mass loss occurred in all other test units. However, there was no statistically significant difference between any of the different treatments in the aerobic units. Investigation of analytical data from the test units indicated that mass loss in aerobic units was due to a combination of dehydration through evaporation of moisture and biological stabilisation processes, and that the latter were not significantly enhanced by the addition of commercial pit latrine products. It was concluded that there was no evidence to support claims that pit latrine additives could extend the life of a pit latrine.

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OPSOMMING Artikel 174 prosedure van die StrafproseswetAlhoewel nuttig, staan artikel 174 prosedure van die Strafproseswet die gevaar om misbruik te word as 'n aanspreeklikheidsvermydingsmeganisme, ten koste van die wyer belang van geregtigheid. Dit kan geargumenteer word dat daar reeds gewysdes is waarin hierdie gevaar verwerklik is: Die hoë-profiel saak S v Dewani, waarin die artikel 174 prosedure suksesvol ingespan om die drie beskuldigdes se ontslag te bewerkstellig, kan dien as voorbeeld. Hierdie artikel spoor die oorsprong van artikel 174 van die Strafproseswet in Suid-Afrikaanse reg na, en toon aan dat die omstandighede wat in die verlede aanleiding gegee het tot die skep van artikel 174, nie meer teenwoordig is nie. In die lig van hierdie afwesigheid van geskiedkundige regverdigingsfaktore, en bedag op die gebrek aan sekerheid in die regterlike uitoefening van die ontslag-toets, assesseer hierdie artikel die nut, nodigheid, en gepastheid van die artikel 174 prosedure in huidige Suid-Afrikaanse reg. Ten einde emuleer-waardige beste praktyk te vind, word Kanadese and Engelse benaderings tot die ontslag-prosedure onder die loep geneem.If the application of the provisions of section 174 favour the accused they are discharged from prosecution without having to testify -but with the 1 Act 51 of 1977 (hereafter the CPA).