Quality Control. Quality control (QC). Q uality control, focuses on the end result, such as testing a sample of items from a batch after production . Inspection takes place at all stages of the process from design to dispatch
Quality control, focuses on the end result, such as testing a sample of items from a batch after production.
Inspection takes place at all stages of the process from design to dispatch
Basically quality control tests that the standards laid out by the quality assurance standards have been met
Quality control checks will normally include:
weight checks to make sure the product is the required weight
visual checks to make sure it looks the way it should
temperature checks to make sure it is being kept at an appropriate temperature
pH checks to make sure the food has the correct acidity/alkalinity
microbiological checks to make sure bacteria are not at harmful levels
chemical checks to guard against chemical contamination
metal checks to guard against contamination by metals (usually at the packing stage, using a metal detector)
organoleptic checks to check flavour, texture and aroma by sampling the food product
1. The operational techniques and activities that sustain the product or service quality to specified requirements.
2. The use of such techniques and activities.
3. Operations intended for the assessment of the quality of products at any stage of processing or distribution .
4. Part of quality assurance intended to verify that components and systems correspond to predetermined requirements.
Basically Quality assurance sets the standard for quality control
Quality control is inspecting, measuring and testing to make sure the standards set out by quality assurance are being met.
Total quality management
Inspection takes place at stages
Quality managers need to be adaptable in order to meet customer expectations and to ensure legal compliance. They employ a variety of measures and management systems, including the ISO 9000, total quality management (TQM), as well as the continuous improvement process.
The work of the quality manager will be affected by the nature of the employing organisation but is likely to include some or all of the following activities
devising and establishing a company's quality procedures, standards and specifications;
reviewing customer requirements and ensuring that they are met;
working with purchasing staff to establish quality requirements from external suppliers;
setting standards for quality as well as health and safety;
making sure that manufacturing or production processes meet international and national standards;
defining quality procedures in conjunction with operating staff;
setting up and maintaining controls and documentation procedures;
monitoring performance by gathering relevant data and producing statistical reports;
preparing clear explanatory documents such as customers' charters
Quality control inspectors make sure that products meet standards of quality and safety. For example, they measure and weigh products, examine samples and test them.
Quality control inspectors work in a wide range of industries, including food and drink, pharmaceuticals and electronics
ISO9000: 1994 is a generic standard in several parts:ISO9001: Quality Systems - Model for Quality Assurance in Design/Development, Production, Installation and Servicing. (all of system)ISO9002: Quality Systems - Model for Quality Assurance in Production, Installation and Servicing.ISO9003 - Quality Systems - Model for Quality Assurance in Final Inspection & Test.
To follow ISO 9000, a company's management team decides quality assurance policies and objectives. Next, the company or an external consultant formally writes down the company's policies and requirements and how the staff can implement the quality assurance system.
Once this guideline is in place and the quality assurance procedures are implemented, an outside assessor examines the company's quality assurance system to make sure it complies with ISO 9000.
A detailed report describes the parts of the standard the company missed, and the company agrees to correct any problems within a specific time.
Once the problems are corrected, the company is certified as in conformance with the standard.
Finding the variance of a set of measurements
Find standard deviation of the following readings
Mean (average) = (6+5+4+7+3)/5 = 25/5 = 5
( ∑x2/n) – x (av) =( (36+25+16+49+9)/5) – 25
= (135/5) -25 = 27 -25 = 2
S = √2 = 1.41 (variance( sigma) = 1.41)
The objective of Six Sigma quality is to reduce process output variation so that on a long term basis, which is the customer’s aggregate experience with our process over time, this will result in no more than 3.4 defect parts per million (PPM
A six sigma process is one in which 99.9999966% of the products manufactured are statistically expected to be free of defects (3.4 defects per million),
Six Sigma team leaders (Black Belts) work with their teams (team members will normally be people trained up to 'Green Belt' accreditation) to analyse and measure the performance of the identified critical processes. Measurement is typically focused on highly technical interpretations of percentage
There must be evidence of the existence of a system
A record of the correct operation must be kept
This is important to trace evidence of inspection in case of future complaints or problems
Mean time between failures (MTBF) is the predicted elapsed time between inherent failures of a system during operation
MTBF can be calculated as the (average) time between failures of a system