Hanson's product range of more than 300 bricks means that it is no small task to carry out the constant routine testing that is necessary to comply with the relevant British Standard.
In addition to the quality control which is monitored constantly at each of the company's factories, standard tests measure such parameters as frost resistance, dimensional tolerance, soluble-salt content and the physical properties of bricks such as compressive strength and water absorption.
Compliance with British Standards and with ISO 9001 is mandatory, and all materials that are delivered to the customer are covered by the documentation. Hanson considers it particularly important to have such benchmark standards to assure the end user of the product quality.
Some of the BS tests are controversial.
For example, the dimensional tolerance test, rather than measuring an individual unit, measures the total length of 24 bricks and demands that this measurement should be within the given range. Although tests like this seem conservative, they are written with practicality in mind, given that with many hundreds of clay facing bricks available in the UK there are many different characteristics to take into account. These need to be covered fairly by one standard.