In a quality control procedure, a process is considered at an acceptable quality level if the proper statistic employed to construct a control chart does not fall exterior the bounds of the acceptable quality limits. Or else, the process is considered at a rejectable control level.
The use of the abbreviation AQL for the phrase acceptable quality limit has recently been transformed in the standards issued by a minimum of one national standards organization (ASQ/ANSI) to relate to the word acceptance quality level. It is not clear whether this interpretation will be brought into general usage, however the underlying meaning stays the same.
Statistical Quality Control is the word used to explain the set of statistical equipment used by quality experts. SQC is employed to analyze the quality issues and solve them.
Statistical quality control describes the usage of statistical methods in the maintaining and monitoring of the quality of services and products.
All the tools of SQC are beneficial in evaluating the quality of services. SQC uses various tools to analyze quality problem.
1) Descriptive Statistics
2) Statistical Process Control (SPC)
3) Acceptance Sampling
Descriptive Statistics involves explaining quality relationships and characteristics. SPC involves inspect random sample of output from procedure for characteristic. Acceptance Sampling involve batch sampling by inspection.
Quality control is a process or pair of procedures intended to make sure that a performed service or manufactured product adheres to a defined set of quality criteria or fulfills the requirements of the customer or client.
QC is similar to, however not identical with, quality assurance (QA). QA is described as a process or set of procedures intended to make sure that a service or product under development (before work is done, as opposed to afterwards) fulfills specified requirements. QA is sometimes expressed along with QC as an individual expression, quality assurance and control (QC/QA).
In order to apply an effective QC program, an enterprise should first choose which specific standards the service or product must satisfy.
Then the extent of QC actions should be determined (for instance, the percentage of units to be analyzed from each lot). Next, real-world data should be collected (for example, the percentage of units that fail) and the outcomes reported to management personnel.