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Definition of Quality Assurance and Control – Differences and Examples

What is Quality Assurance (QA)?

Quality assurance (QA) is an aspect of quality management that is responsible for the implementation of specific industry standards within the production of a product/service.


Quality Assurance (QA) Vs Quality Control (QC)

Quality assurance (QA) and quality control (QC) are both part of the quality management process. However, they refer to different stages of the quality management of products or service. The difference between quality control and quality assurance is:

Quality assurance (QA) – is associated with the implementation of standards (such as ISO 9000) during the production stage.

Quality control (QC) – is associated with managing the fulfilment of quality requirements through techniques, such as inspection, to determine if the product/service meets the quality requirements.


The Quality Assurance (QA) Process:

At TWI, quality assurance (QA) is managed via conformance with ISO 9001:2015 and ISO 17025:2017:

  • Quality assurance (QA) policies and objectives are outlined by the quality management system and governed by a management team
  • The outlined assurance policies and objectives are documented by the company in the quality management system
  • This documented information is then put into practice and implemented into the operational activities, including quality of products or services. The quality improvements and status verifications are implemented following an internal audit.
  • An external assessor examines the company's quality assurance (QA) systems to ensure that TWI complies with requirements of ISO 9001:2015
  • The external assessor then produces a findings report to detail any aspects of the standard not complied with
  • The company is then given the opportunity to comply with these aspects within a time frame of usually 4-6 weeks
  • The company quality management system is then reviewed by the external assessor
  • If all standards are complied with, the company will be given certification for conforming to the required standards


Industry Quality Assurance (QA) Examples:

Quality assurance (QA) is an issue that must be addressed by standards and regulation. TWI has vast experience with different industry standards (including ISO 9001) and other quality assurance related tools. These include:

  • The development of BeamAssureTM: TWI has developed a quality assurance (QA) tool that helps monitor beam characteristics. 
  • TWI was part of the ManSVS Group Project which developed an online platform for the design of 3D printed parts.
  • A new post-manufacture inspection of adhesive bond line integrity offers increased quality assurance (QA) without significant time penalties. 
  • TWI transitioned to the latest version of the international standard ISO 9001:2015
  • TWI welding codes and standards; TWI has experience in operating codes and standards in all industries; relevant standards ensure quality assurance (QA). 
  • The SignaStir project has developed a system to detect critical defects in welds, as a response to the need for an effective in-process quality assurance (QA) and inspection method.
  • TWI carried out tests to gain the mechanical properties of adhesives. This is important as these determine the final performance of the adhesive joints. The method of testing both quality assurance (QA) and quality control (QC) when dealing with adhesive joint mechanical properties.


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