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There are no ifs, buts or short-cuts; the only option available for Sri Lanka is to develop a unified building code and a mechanism to issue conformity certificates for the materials and products used for the construction industry – Pic by Shehan Gunasekara
Context
Benjamin Franklin is known as the Father of United States of America. He was witty and intelligent. Once he said: “If you would not be forgotten, as soon as you are dead and rotten, either write things worth reading, or do things worth the writing.” I am no prodigy. However, this is an attempt to follow his advice.
An inquisitive engineer made a valuable comment on a previous column I published ‘The need of the hour – A building code for Sri Lanka’ (Daily FT – 11 July). He requested my views on the poor quality materials, ubiquitous in the Sri Lankan market. This article is a kind of response to that query.
Again, I don’t need to go beyond Benjamin Franklin to highlight the issue. He famously said: “The bitterness of the poor quality remains long after the sweetness of the low price is forgotten.” This is about that bitter reality.
Confused terminology
The three terms quality, standard and condition are used interchangeably, although the meaning of each of these terms is technically different. Quality means the conformance to the set product requirements. The product requirements are set by the designer, taking into account of the customer requirements.
In case of a building, the designer and the client set the requirements and the final quality is to be achieved by satisfying these requirements. However, the external parties have no control over the autonomy of the manufacturers who set these requirements unless the manufacturers voluntarily follow the requirements of a universally known standard. The standard is the level of quality.
This can be legislatively enforceable standard or a standard developed mutually by the manufacturer and the client. Then, the condition is a measure of the health of the product. It is a subjective measure and the current condition will impact the product’s performance during its remaining economic life. A building can be of high standard, but, of poor condition due to a poor maintenance regime in place. Also, there could be a poor quality product of good condition. Of course, the poor quality product will not last long due to the use of poor quality materials to produce it.
Standard bricks and designs
Once, the Lord Buddha requested Kisagothami who was carrying her deceased son, to find mustard seeds from a house where death had not occurred. This was intended to raise her awareness that the death was and still would be an inevitable phenomena, for all beings. In Sri Lanka, if someone is challenged to find a correct size brick from a kiln, there is a high possibility of him/her coming back without a brick.
I vividly remember the long hours spent on doing tedious structural design calculations, at the university, assuming standard size bricks, optimum quality cement, consistent ten millimetre thick mortar layers, steel members and reinforcements of British Standards quality, and specific grades of concrete. When practised in the field, I realised that the reality was far away from the fantasy structural design world. Consequently, for actual designs, inflated safety factors had to be applied to cover the never improving inferior standards of materials and the poor workmanship. This was, in addition to the recommended safety margins set by the codes.
Structural designs are done such a way that any local failures would not trigger progressive failure of the rest of the structure. However, if an engineer designs a structure just according to a Code of Practice without taking into account of the very poor standard construction materials, the designer runs into the risk of producing an under-designed structure. For such a structure, a local failure, maybe due to a mistake of the design, could trigger the progressive failure of the structure. This is a side-effect of the use of inferior standard materials and workmanship.
The easy option taken by the experienced engineers is to perform over-designs. This is akin to the treatment of the symptoms rather than the cause. Over designs essentially would mask the poor standard of material and workmanship. Over-designs cost clients dearly. It inflates the capital value of the structure artificially. It also promotes inferior standard work practices for ever, unabated.
The crooked, out of plumb brick walls, columns and beams are covered with massive layers of mortar and the designer’s expectation of vertical load transfer through load bearing walls to the foundation is literally vanished under the mortar. This is a time bomb covered by a cosmetic wrap. How long could this be allowed to go on? This is like, the nation walk towards an incoming tornado, eyes shut.
Global market
The Sri Lankan construction industry has been rapidly expanded during last twenty years, due to mega construction projects and it operates now in a global market place utilising a vast range of construction materials and products predominantly manufactured overseas. Hence, it is a mammoth task to ascertain whether the imported materials and products have been manufactured in accordance with an acceptable Code of Practice or Standard, unless product manufacturers support this verification process through labelling or documentation.
Even with such information, the genuineness cannot be guaranteed. The safety of the end user of the product or structure is compromised due to the use of substandard materials. This would affect the service life of the product or the structure.
Compliant development
Recently, a few buildings collapsed in Sri Lanka and there was a reasonable suspicion that these failures were due to under designs and substandard material and workmanship. This is an alarming situation, indeed. By the way, it is not yet clear that the Sri Lankan authorities paid any attention to my previous suggestion to develop a unified building code for Sri Lanka.
However, even having a code is only the first step of a long process. Proper designs according to the code must be followed up by the use of compliant material which is to be legally enforced through a well-developed mechanism. This mechanism must be underpinned by the following guiding pillars.
Pillar 1 – The building construction activity must be complied with all legal and safety requirements specified in Sri Lanka. This means the construction activity could be defended legally.
Pillar 2 – There should be a document clearly specifying the product standards and required evidences of conformity. Product Standards should have a reference to the Sri Lankan standards or any other relevant international standards.
Pillar 3 – Selection of products should be done with the view of the performance of end-product, which is a combination of many products together, the intended use of the end-product and the risk exposure. This will drive the selection of required evidences of conformity.
Pillar 4 – Meeting with the specified standards must be demonstrated by the conformity assessment which could be in terms of the product certification by an accredited certifying authority and also by the representative sample inspection and testing.
Pillar 5- The manufacturing source of the product and details of authenticity must be recorded and kept.
Pillar 6 – The use of the products without furnishing evidences of products conformity, must be legally banned.
Product conformity
Product conformity is the testing of performance to prove that the material, component, joint or assembly is capable of conforming to the requirements of the relevant Standard. Developed countries have dual approaches on this.
Informative approach
Some countries has made product conformity ‘informative’ only. This means the builders can voluntarily claim that they have fulfilled the product conformity requirements. This approach is acceptable if there is a significant control over importation of building materials to the country by the authorities and the material importers submit all necessary conformity documentation as a part of importation and distribution process.
Further, this approach works well when designers have the legal responsibility to specify product conformity requirements as a part of the design process and the builders fulfil these material selection requirements, otherwise risking the revocation of builders’ licences.
Within such a professional work environment, the builders would issue trade based compliance certificates for all construction works such as electrical, mechanical, plumbing etc. stating that the construction have been completed in accordance with specified standards and quality. One copy of each signed and dated compliance certificate is to be submitted directly to the licencing authority and the client will get a copy of the compliance certificate as well. These are legal documents and if inaccurate information is submitted, the builder is liable for prosecution.
Normative approach
The normative approach dictates that the product conformity is compulsory. This means representative samples of material from each batch must be tested and a certificate of conformity must be taken from an accredited testing authority before using the material for construction works.
As an example, in Australia, there is an independent certification body called “The National Association of Testing Authorities” (NATA) and it provides accreditation to the material testing organisations, to enable these organisations to issue conformance certificates for materials and products, certifying the conformance to the relevant standards. NATA has a comprehensive assessment criteria for determining the competence of a testing organisation before awarding the accreditation rights. This process includes verification of the qualifications, training and experience of the staff, availability of properly calibrated and maintained correct equipment, the use of adequate quality assurance procedures, and the application of appropriate sampling practices. Given the liberal nature of the material and product importation practices prevalent in Sri Lanka and the lack of interest on voluntary application of construction material testing prior to use, the informative approach on product conformity would not work. It should be the normative approach that would give desirable results for a country like Sri Lanka.
Conformity assessment
Conformity assessment is the periodic assessment for manufacturers to check that their products meet the requirements of the product Standard. This assessment will determine a product, process, service or system conforms to specific requirements. The product requirements could be set by a standard code, any other normative document or purely by the customers who use the product through a document such as a contract document.
Generally, Conformity Assessment Bodies (CABs) provide attestations that products, processes and systems would perform as intended. CABs would follow a few structured activities in the process of certifying a product that conforms to the specified requirements. These activities include the testing and inspection of a product, auditing of the quality management system in place for the production process and the assessing of the product and its production process.
The only way ahead
There are no ifs, buts or short-cuts. The only option available for Sri Lanka is to develop a unified building code and a mechanism to issue conformity certificates for the materials and products used for the construction industry. The importers of construction material and products should furnish valid and genuine conformity certificates to the Sri Lanka Customs before proceeding with importation. Local manufacturers must do the same before placing their products in shelves for trading. These requirements must be legally enforced. The violators must be punished as the professional negligence and the use of non-conformed materials and products causing failures of structures, is a crime, as already recognised in the developed countries.
(Eng. Janaka Seneviratne is a Chartered Professional Engineer and a Fellow of both the Institution of Engineers, Sri Lanka and Engineers Australia. He currently works for the Australian local government sector. His thirty years of experience as a professional engineer encompasses Sri Lankan and overseas work environments and many sub-branches in civil engineering and management. The author is contactable via [email protected].)