How to state the janka rating this is where the janka rating starts to get confusing for most.
Highest janka rating hardwood.
These ratings were calculated using the janka hardness test which measures the force needed to embed a 444 inch steel ball to half its diameter in a piece of wood.
In laymans terms it is a way to measure a woods resistance to denting.
Yet these are not hardwoods.
Janka ratings are from 0 to 4 000 the lower the rating the easier the species is susceptible to scratches and dents.
For hardwood flooring the test usually requires a 2 6 sample with a thickness of at least 6 8mm and the most commonly used test is the astm d1037.
The janka rating is a measure of the amount of force required to push a 444 diameter steel ball half way into a piece of wood.
The higher the rating the more resistant the floor will be to dents and scratches.
Forest service list the relative hardness for numerous wood species used in flooring.
Some of the hardest floors available are strand woven bamboo and eucalyptus where you may see janka ratings at levels from 3 800 to over 5 000 making them harder than all hardwoods.
The highest rating on the scale is a 4000 making for an extremely hard wood also not likely suitable for flooring because it would be so difficult to saw.
A common use of janka hardness ratings is to determine whether a species is suitable for use as flooring.