The BS EN ISO 11432:2005 tests a sealants ability to resist being compressed, the sealant is applied to aluminium, glass or mortar (depending on it's intended use) and left to fully cure for 28 days. Some sealants will also need cycles of 70°C dry heat and immersion in 23°C water (again dependant on the intended use).
After the curing and cycling the sealant is compressed in a machine by either 20 or 25% (depending on requirements for the sealant) and the force applied recorded. The results are then converted into N/mm2 giving you the secant compression modulus.
