The Janka hardness test measures the resistance of a sample of wood to denting and wear. It measures the force required to embed an 11.28mm steel ball into wood to half the ball’s diameter. This method leaves an indentation. The Janka hardness rating is to determine whether a species is suitable for intended use. The stated results are measured in kilonewtons.
To find out which ratings are attributed to specific timbers, consult our Chop ‘O’ Meter
For more information on Janka visit https://en.wikipedia.org/wiki/Janka_hardness_test