College of Production Technology

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Chris Greenwood – MD, College of Production Technology (CPT)

I have often been asked for the difference between Quality Control and Quality Assurance. Below I have broken them up for you.

What is quality control?

Quality control is a process employed to ensure a certain level of quality in a product or service. It may include whatever actions a business deems necessary to provide for the control and verification of certain characteristics of a product or service. The basic goal of quality control is to ensure that the products, services, or processes provided MEET SPECIFIC REQUIREMENTS and are dependable, satisfactory, and fiscally sound.

Essentially, quality control involves the examination of a product, service, or process for certain minimum levels of quality. The goal of a quality control team is to identify products or services that do not meet a company’s specified standards of quality. If a problem is identified, the job of a quality control team or professional may involve stopping production temporarily. Depending on the particular service or product, as well as the type of problem identified, production or implementation may not cease entirely.

Usually, it is not the job of a quality control team or professional to correct quality issues. Typically, other individuals are involved in the process of discovering the cause of quality issues and fixing them. Once such problems are overcome, the product, service, or process continues production or implementation as usual.

Quality control can cover not just products, services, and processes, but also people. Employees are an important part of any company. If a company has employees that don’t have adequate skills or training, have trouble understanding directions, or are misinformed, quality may be severely diminished. When quality control is considered in terms of human beings, it concerns correctable issues. However, it should not be confused with human resource issues.

Often, quality control is confused with quality assurance. Though the two are very similar, there are some basic differences. Quality control is concerned with the product, while quality assurance is process-oriented.

Even with such a clear-cut difference defined, identifying the differences between the two can be hard. Basically, quality control involves evaluating a product, activity, process, or service. By contrast, quality assurance is designed to make sure processes are sufficient to meet objectives. Simply put, quality assurance ensures a product or service is manufactured, implemented, created, or produced in the right way; while quality control evaluates whether or not the end result is satisfactory.

What is quality assurance?

Quality assurance is the process of verifying or determining whether products or services meet or exceed customer expectations. Quality assurance is a process-driven approach with specific steps to help define and attain goals. This process considers design, development, production, and service.

This method checks the quality of completed products for faults. Quality inspectors measure or test every product, samples from each batch, or random samples – as appropriate to the kind of product produced.

  • Advantages – inspection is intended to prevent faulty products from reaching the customer. This approach means having specially trained inspectors, rather than every individual being responsible for his or her own work. Furthermore, it is thought that inspectors may be better placed to find widespread problems across an organization.
  • Disadvantages – individuals are not necessarily encouraged to take responsibility for the quality of their own work. Giving workers responsibility for their own work helps to improve motivation by increasing the interest and variety in the job, so quality assurance tends to be preferred for this reason as well. Other approaches to quality (such as TQM, see below) mean that there is much less need for quality control if the whole process is geared towards ‘zero defects’ or getting it right the first time.

Rejected product is expensive for a firm as it has incurred the full costs of production but cannot be sold as the manufacturer does not want its name associated with a substandard product. Some rejected products can be re-worked, but in many industries, it has to be scrapped – either way, rejects incur more costs.

A quality control approach can be highly effective at preventing defective products from reaching the customer. However, if defect levels are very high, the company’s profitability will suffer unless steps are taken to tackle the root causes of the failures.

The most popular tool used to determine quality assurance is the Shewhart Cycle, developed by Dr. W. Edwards Deming. This cycle for quality assurance consists of four steps: Plan, Do, Check and Act. These steps are commonly abbreviated as PDCA.

At the College of Production Technology (CPT), we offer Quality Assurance training as a Registered Skills Programme or as a Workshop. Please contact CPT on 0860 278 278 or info@cpt.co.za for more information.


At the College of Production Technology (CPT), we offer Quality Assurance training as a Registered Skills Programme or as a Workshop. Please contact CPT on 0860 278 278 or info@cpt.co.za for more information.

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