DESIGN : DEAR PLUMBERS 15
The rational design
By D . S ( Vollie ) Brink Pr . Eng . MSAICE , MPMISA
What is really a “ Rational Design ”?
The people who are not competent or not qualified to do a rational design are mostly the people who are against the rational design . Conversely , the people who are competent and qualified prefer a rational design because of the benefits .
What are the benefits ? The original National Building Regulations were based on three ( 3 ) important principles namely : 1 . Health 2 . Safety 3 . Economy
The health and safety elements have been emphasised over time , but the economic element did not always get the same attention .
The definition of a rational design in the formal document is not acceptable for all the “ designers ” as it is felt that it does not really define it correctly .
People who are not engineers have been involved in the defining of a definition that includes engineering design and construction .
The basis of engineering is science . Science is based in most cases on assumptions , but these assumptions must be proven by practical experience and testing .
A rational design is not a design that is based on applying fixed rules and regulations . It is , and must be , based on sound knowledge of appropriate science and assumptions which are proven .
Vollie Brink is one of the industry ’ s longest-serving wet services engineers . He continues to serve on SABS committees and has been involved in the Green Building Council ’ s Green Star rating system . Brink continues to consult for various organisations while enjoying a wellearned retirement .
The new dispensation has made further progress by means of the Health and Safety Act , but the economic element still needs attention .
There are problems in areas , mostly rural areas , where by-laws are applied as if they are above the Act and formal regulations and applied as if they are the Law and where a rational design is hampered and dictated by a local official who then does not take responsibility for his instructions , which in these cases cause serious costs .
These kinds of cases were referred to the Review Board in the past , which is why there is a dire need for the review board to be re-instated .
There are decisions made that negatively affect the economy and development of certain areas and they must be amiably addressed rather than remaining in disputes and where appropriate by means of rational and innovative , economic solutions .
Most of the disputes can be solved by means of a Review Board and to the benefit of all the responsible bodies from the owner to the institutional officials . Moreover , the local economy will also benefit .
The opposite of a rational design is where the designer diligently applies certain fixed rules and fixed regulations without taking into consideration local conditions and the suitability of these rules and regulations for the specific project and not only the fixed rules and regulations , but also the materials and equipment and the environment .
The selection of these materials and equipment etc ., plays a critically vital role in the economy of the area .
The economy is an unimportant element of a rational design as the cost of a rationally designed project can in most cases be reduced .
The “ deem-to-satisfy-rule-design ” is when everybody is issued with a size 55 overhaul and a rational design is like when everybody is issued with a “ tailor-made ”, “ fit-exactly ” overhaul .
I feel that all designs by engineers must be rationally designed projects with all the advantages of such a design . PA
Kind regards
D . S . Brink
Pr . Eng .
“ There is a dire need for the review board to be re-instated .”
October 2022 Volume 28 I Number 8 www . plumbingafrica . co . za