11, The Quality management system


11.1 Quality philosophy
Companies perceived as producing products of poor quality have either failed or are struggling for survival, while those recognized for quality have generally flourished. During 1970s and 1980s, product defect rate of Japanese was 10-100 times lower than his competitors. Now US and Europe have eliminated this gap with the quality level increasing from 3 sigma (AQL is 3/1000) to 6 sigma (AQL is 2 per million) in electron industry. The consumers who buy products with good quality are more loyal than those who buy based on price and always change to competitors' products with lower price. We can also find that producers with good quality have lower cost because of using advanced management method to avoid quality loss caused cost. The approaches of Deming, Juran, Shingo and others actually support each other producing total quality management (TQM) which deploys quality management in all crossed departments but not only quality department, in every area of process but not the end products and by every personnel but not only quality people.
11.2 What is quality
Quality is the competence of product or service to satisfy the customer's need or expectation. In other words, quality is customer oriented with promising something to consumer. Specific quality dimensions varies in different products with the general references as the followings.
1, Performance. Performance is specificication promisiing to and recognized by customer such as density, viscosity and volume etc.
2, Features. Such as attracting desining of the packing, high resolution screen of cell phone etc.
3, Reliability and durability. Reliability is the quality consistency under normal maintenance, production and consuming environment such as in normal living environment, one type of TV can always displays the expected pictures. And durability measures the product life etc.
4, Maintainability and serviceability. Maintainability measures whether one product such as milk filler can be mainatined to keep its quality and serviceability measures whether there is after sales service such as on-site support or remote telephone hot line assistant support.
5, Sensory charicteristics. Products with high nutrition without being tasty or good smell are generally not good quality products.
6, Ethical profile and image. Different people have different believing affecting their judge or acception of some specific products.
11.3 Quality cost audit
We need to know wether it is worth to produce one specific level of quality. In other words, we need to find the equivalent point of quality input and output. Generally, we need to consider failure cost, inspection cost and prevention cost such as quality control. Traditionally, the cost distribution of failure, inpection and prevention are 50-80%, 15-40% and 5-10%. After TQM, the cost distribution of failure, inpection and prevention are 20-50%, 15-40% and 25-50%.