Using a Durometer to measure the hardness of sponge rubber
A fast way people use to check the hardness/softness of closed cell sponge is with a Shore Durometer device. Normally the “oo” scale.
Using a hand held Durometer is very subjective, hand pressure, ambient temperature, cell size of the sponge are just a few of the variables that make the procedure not technically reproducible.
ASTM and other recognized standards do not have durometer as part of the specification. What is used is compression deflection which we will discuss in a future blog.