There are three legitimate routes to acquiring the official :
is a European Standard that has been adopted as a British Standard. Its full title is: "Drainage channels for vehicular and pedestrian areas – Slotted top surfaces and/or gratings – Requirements, testing and marking." bs en 7721 pdf
Raw test results are converted into Normalised Compressive Strength ( There are three legitimate routes to acquiring the
: Allows manufacturers to repair high-value assemblies rather than scrapping them due to minor defects or damage. Oven-dry: Specimens are dried to a constant mass
BS EN 772-1 specifies the procedure to determine the compressive strength of masonry units (bricks, blocks, etc.) by applying a compressive load until failure. The standard ensures consistent, comparable strength results across laboratories and manufacturers.
Material strength can vary significantly based on moisture. The standard specifies several conditioning paths prior to testing: Samples are stored at and 60% relative humidity for a minimum of 14 days. Oven-dry: Specimens are dried to a constant mass at and cooled before testing.
The standard is well-structured, clear, and concise, making it easy to follow and understand. However, some users may find the scope and applications limited to specific types of masonry units. Overall, it's an excellent resource for those involved in the construction industry.