Quality control is the part of quality management that ensures products and service comply with requirements. It is a work method that facilitates the measurement of the quality characteristics of a unit, compares them with the established standards, and analyses the differences between the results obtained and the desired results in order to make decisions which will correct any differences.
Technical specifications define the type of controls that must be carried out to ensure the construction works are carried out correctly. They include not only products materials, but also the execution and completion of the works.
One way of controlling quality is based on the inspection or verification of finished products. The aim is to filter the products before they reach the client, so that products that do not comply with requirements are discarded or repaired. This reception control is usually carried out by people who were not involved in the production activities, which means that costs can be high, and preventative activities and improvement plans may not be effective. It is a final control, located between producer and client, and although it has the advantage of being impartial, it has a large number of drawbacks, such as slow information flows, and that the inspectors are not familiar with the circumstances of production and are not responsible for the production quality.