TWI Frequently asked questions
by John Weston
Quality is an important issue and is well addressed by a number of Standards.
ISO 8402:1995 Quality management and quality assurance. Vocabulary.
This Standard notes that 'confusion has arisen in understanding the terms quality control, quality assurance, quality management and total quality management'. The Standards goes on to say that 'in simplified terms, quality control concerns the operational means to fulfil the quality requirements, while quality assurance aims at providing confidence in this fulfilment, both internally and externally to customers and authorities'. Within the Standards, the term 'ensure' means to make sure or certain, while 'assure' means to give confidence to oneself or to others.
Specifically, the Standard gives the following definitions:
3.4 quality control - operational techniques and activities that are used to fulfil requirements for quality.
3.5 quality assurance - all the planned and systematic activities implemented within the quality system and demonstrated as needed to provide adequate confidence that an entity will fulfil requirements for quality.
In developing products and services, quality assurance is a management system implemented by a company to provide objective evidence that a product or service is meeting specified requirements. Many companies have a separate Department devoted to quality assurance. A quality assurance system is said to increase customer confidence and a company's credibility, to improve work processes and efficiency, and to enable a company to compete better with others. Quality assurance was initially introduced in World War II when munitions were inspected and tested for defects after they were made. Today's quality assurance systems emphasise catching defects before they get into the final product,a philosophy known as 'right first time' - on the basis that prevention is less expensive than the cure.
ISO 9000: Quality management systems - fundamentals and vocabulary, is an international Standard that many companies use to ensure that their quality assurance system is in place and effective. Definitions withinISO 9000 include:
3.2.8. Quality Management - co-ordinated activities to direct and control an organisation with regard to quality.
3.2.11 Quality Assurance - part of quality management focused on providing confidence that quality requirements will be fulfilled.
3.2.10 Quality Control - part of quality management focused on fulfilling quality requirements.
(3.1.2 requirement - need or expectation that is stated, generally implied or obligatory.)
The objective of implementing ISO 9000 is said to guarantee that the company delivers quality products and/or services. To comply with ISO 9000, a company's management team decides quality assurance policies and objectives. Next, the systems and procedures by which the company will implement the requirements of ISO 900 are documented.
Once these documents are in place and the quality assurance procedures have been implemented and internally audited, an outside assessor examines the company's quality assurance system to make sure it complies with ISO 9000. The assessor produces a detailed report describing the parts of the Standard not adequately addressed, and the company then corrects deficiencies (within a specific time). Once the problems are corrected, the company is re-audited by the external assessor and, provided that there are no further areas of non-conformance, the company can be certified as in conformance with the Standard.
Within the 9000 series of Standards, welding is treated as a 'Special Process' since welds cannot be fully verified by subsequent inspection and testing of the product to ensure that the required quality standards have been met. ISO9000 does not include any specific requirements for the control of these special processes. To fill this gap, EN ISO 3834:2005 Quality requirements for welding, fusion welding of metallic materials has been developed. This Standard addresses the quality assurance and quality control issues for fusion welding. The guidance given by this set of Standards could also be used to give guidance with other joining technologies.
The guidelines have been prepared to describe welding quality requirements suitable for application by manufacturers, which use welding as a means of fabrication. While ISO 3834 can be a useful tool in support of ISO 9000 it canalso be used as a stand-alone document.
TWI supports its Industrial Member companies in training for, and in the implementation of, ISO 3834 and Total Quality Management. There is also wide support given in the area of qualitycontrol in manufacture, especially when using joining technologies.
Further information
How can a fabricator satisfy ISO9001/2, ISO3834 and EWF requirements?
What is 'Total Quality Management (TQM)'?
