Author: Jim Riley Last updated: Sunday 23 September, 2012
Production & operations - Managing quality
Achieving high quality does not happen by accident. The production process must be properly managed to achieve quality standards. Quality management is concerned with controlling activities with the aim of ensuring that products and services are fit for their purpose and meet the specifications.
There are two alternative approaches to managing quality
Quality control
A definition of quality control is:
The process of inspecting products to ensure that they meet the required quality standards
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.
The main objective of quality control is to ensure that the business is achieving the standards it sets for itself.
In almost every business operation, it is not possible to achieve perfection. For example there will always be some variation in terms of materials used, production skills applied, reliability of the finished product etc.
Quality control involves setting standards about how much variation is acceptable. The aim is to ensure that a product is manufactured, or a service is provided, to meet the specifications which ensure customer needs are met.
At its simplest, quality control is achieved through inspection. For example, in a manufacturing business, trained inspectors examine samples of work-in-progress and finished goods to ensure standards are being met.
Advantages of quality control
With quality control, inspection is intended to prevent faulty products 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 organisation.
Disadvantages of quality control
A major problem is that individuals are not necessarily encouraged to take responsibility for the quality of their own work.
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 substandard product. Some rejected product 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.
Quality Assurance
A definition of quality assurance is:
The processes that ensure production quality meets the requirements of customers
This is an approach that aims to achieve quality by organising every process to get the product ‘right first time’ and prevent mistakes ever happening. This is also known as a ‘zero defect’ approach.
In quality assurance, there is more emphasis on ‘self-checking’, rather than checking by inspectors.
Advantages of quality assurance include:
Costs are reduced because there is less wastage and re-working of faulty products as the product is checked at every stage
It can help improve worker motivation as workers have more ownership and recognition for their work (see Herzberg)
It can help break down ‘us and them’ barriers between workers and managers as it eliminates the feeling of being checked up on
With all staff responsible for quality, this can help the firm gain marketing advantages arising from its consistent level of quality
Total quality management (“TQM”) is a specific approach to quality assurance that aims to develop a quality culture throughout the firm. In TQM, organisations consist of ‘quality chains’ in which each person or team treats the receiver of their work as if they were an external customer and adopts a target of ‘right first time’ or zero defects.
Quality Control or Quality Assurance – which is best?
Which approach to managing quality is best? Here is a summary of the main considerations:
Quality Assurance
Quality Control
A medium to long-term process; cannot be implemented quickly
Can be implemented at short-notice
Focus on processes – how things are made or delivered
Focus on outputs – work-in-progress and finished goods