Quality Assurance (QA) is a set of defined processes for systematic monitoring and evaluation to assure product quality.
Quality Control (QC) is the process of confirming that the product meets the specifications. It includes the checking and testing of manufacturing procedures as well as the final products. The results from these tests are compared with a set of defined acceptance criteria. By carrying out QC testing during manufacturing, defects can be identified in a timely manner, allowing for the product flaw to be rectified and if required, adjustments to be made in the manufacturing process to prevent further defective output.
In welding, QA/QC plays a vital role in ensuring sound and reliable welds are produced and in minimizing rework.