Plumbing Africa October 2019 | Page 57

55 FEATURES Successful laboratories are the result of extensive planning, collaboration, and coordination between professionals, including plumbers. deemed to satisfy. Deem-to-satisfy rules are merely a recipe for how to comply with the performance. • A ‘rational design’ is the domain of the design engineer, wherein “people often do not read the regulations clearly, because the design has to be signed off by someone registered as an engineer, architect or scientist – no other.” Brink explains that this is being abused in South Africa – a country that has all the right regulations in place, but which are seldom enforced. • An Agrément certificate, which registers designs at the CSIR, “in which case the design is done according to the Agrément certificate and not to Part P”. nuisance, pose a health threat, or be unsafe, and piping must be correctly sized to convey the effluent safely to the municipal sewage connection. Sanitary drainage piping quality “In my view, a blocked drain that overflows inside a building or even in a public area is a ‘serious health threat’ and such situations must be mitigated by means of correct and innovative rational design by a competent registered civil or mechanical engineer,” says Brink. The most important elements of all parts of the NBR are health and safety, but also economic viability. Unfortunately, the NBR does not address the water and sanitation services of a laboratory, hospital or clinic per se, and therefore the latter must be designed as a rational design by a competent engineer, or as R158 states, an ‘experienced engineer’. This definition, however, is not sufficient since it does not define the level of competence required. It therefore lends itself to abuse by persons not fully competent or not even classified as a registered professional engineer, and who do not possess the necessary level of experience or expertise. “The difficulty is that there are different types of laboratories – in industry, schools, testing labs – which all differ based on what the scientists do and what goes into it. For instance, there has been rapid growth of testing laboratories due to changes in emphasis at the South African Bureau of Standards (SABS) over the past decade. I’ve personally designed many laboratories, which typically will have a drainage system with hot and cold water. With a few exceptions it is not unlike an ordinary house. The important difference is that it must have backflow prevention. A mortuary is also a lab, and for instance you can get back-siphonage after washing bodies, resulting in body bits and pieces entering the water system. There are also acids and other chemicals to be found in a lab, and this often requires special glass or stainless-steel piping in the plumbing, depending on the aggressiveness of the effluent. “The performance of a sanitary drainage system is specified in SANS10400-P: P2, which forms one of seven ‘regulations’ of SANS10400-P. The most important elements of the performance requirements are that the sanitary drainage system must not cause a “This is an aspect of a ‘rational design’. Regulation seven provides that you shall not discharge industrial waste into a municipal sewer system. It must be collected by a waste company and disposed of. But there are no details provided in Part P. October 2019 Volume 25 I Number 8 “The difficulty faced by designers of laboratories and healthcare facilities is that there are no standards in force governing their specifications.” www.plumbingafrica.co.za