This article is about: What is Quality Control and What is Quality Assurance and their Application in the Construction Industry
What is Quality Control QC?
Quality is defined as 'fitness to purpose', i.e. in terms of Construction it is providing a building which provides an appropriate quality for the purpose for which it is intended. The price to be paid for a building is a reflection of the expectations of quality - A cheaper building probably uses inferior materials and is likely to be less attractive and less durable. The quality is also related to the timing of when it is delivered.
Quality Control in the construction industry can be looked at as having three elements:
- To produce a building which satisfies the client
- To produce a building where quality is related to the price.
- To produce a building in which sufficient time is allowed to obtain the desired quality.
Like most other aspects of construction management quality control has to be planned. Planning seeks 'order' and a quality control system for a construction project reflects this sense of order. It may be seen to be in five basic stages:
- Setting the quality standard or quality of design required by client.
- Planning how to achieve the required quality, construction methods, equipments, materials and personnel to be employed.
- Construct the building right first time.
- Correct any quality deficiencies.
- Provide for long term quality control through establishing systems and developing a quality culture.
It is obvious that quality is proportional to costs associated with the construction process. Costs associated with quality need to be identified for management decisions. The costs of quality can be broken down as follows:
- Failure costs: The costs of demolishing and rebuilding, the cost of production time, delays to other gangs
- Appraisal costs: The cost of inspection and testing.
- Prevention costs: The costs of providing better designs, more training to reduce failure costs, more maintenance.
What is Quality Assurance QA?
Quality assurance is a mechanism for ensuring that the construction process takes place within the framework of a quality management system. This suggests that quality assurance defines the organization structure, tasks and duties for implementing quality management.
In 1987, the Building research establishment surveyed the quality problems on Britain's construction sites. They found that half of the faults were design related, and 40% of the problems arose from faulty construction. 10% were product failing.
- misunderstanding the client's brief to develop the design
- using information which is incorrect or out of date
- misunderstanding of the client's expectations of quality standards
- lack of co-ordination between the designers.
- Loose or inappropriate specifications
- Not building to drawings or specifications
- poor supervision leading to bad workmanship
- insufficient management of the quality of construction.
- In order to eliminate those potential problems many clients have looked to quality assurance to reassure them that they will get the right building without undue quality problems.
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