The Brinell test makes a large impression on the surface of the piece tested.

a$.$ Unless such a large impression can be tolerated, and often it cannot, the test is destructive.

b$.$ However, the large impression is advantageous because it gives a more representative result than would a smaller impression which would be more sensitive to local soft or hard and inhomogeneities.

c$.$ The size of the impression also renders the test less sensitive to the presence of rough surface finish and mill scale than is the case when tests are used which rely on small indentations.

d$.$ All of the above