Many in the construction industry are aware of the standards for quality implementation, however, newcomers may assume the concepts of quality assurance and quality control are one and the same. It should be general understanding that these two concepts, although aimed at same purpose, are actually dissimilar. The means by which quality assurance and control are achieved is different along with the assigning of responsibilities to stakeholders.
Quality Assurance is the action of ensuring that the defined processes to achieve the documented quality requirements and standards are strictly adhered to. This action also takes into cognizance the outcome from the quality control process, as it helps to know which processes may not have been followed through. For example, say the process to obtain a concrete grade of 50 N/mm2 has been stated that 0.2 water/cement ratio be used as well a certain quantity of super-plasticizer, then these parameters are the target for quality assurance. During the concrete mixing process, the engineers and workmen are to ensure that these figures from the quality document do not vary on site.
Quality Control is the act of monitoring and recording results of executing the quality activities to assess performance of the finished product or item and recommend necessary changes. The activities involved is comparing the recorded values of the product or item against the specified standards in the quality document or project specifications. It is through quality control that we can ascertain that a quality assurance process was effective or if some changes are required.
The table below shows some differences between the two concepts:
The Responsible Parties for Quality
A project can have high quality standards only if the quality management plan trickles down from top to bottom. There are a number of upcoming contracting forms which work on projects but do not seem to meet the quality standards they desire. They sometimes feel their workmen are the problem and thus, there is constant recycling of employees due to the desire to improve the company’s quality on projects; this is a misconception. According to the Project Management Institute’s Body of Knowledge, PMBOK 5th Edition, “quality is the primary responsibility of the Management of a company”. The table below shows the hierarchy of stakeholder responsibility to quality:
In all, quality assurance and quality control are separately important concepts to which responsibility needs to be assigned to the appropriate stakeholders. The best option is to be proactive, if however there are some unforeseen occurrences, then corrections need to be made. Quality is not inspected into a project, but rather, it is planned.
1 – PMBOK® Guide – Fifth Edition (Project Management Body of Knowledge)