Southern Association of Colleges and Schools Commission on Colleges. Bob Jones University is a candidate for accreditation with the Southern Association of Colleges and Schools Commission on Colleges to award associate, baccalaureate, masters, and doctorate degrees.
hthÂ® calcium hardness increaser, 4 lbs. hthÂ® calcium hardness increaser, 4 lbs., is used to raise the calcium hardness of swimming pool water. Low calcium hardness may cause the pool water to be corrosive, resulting in damage to pool surfaces and equipment.
The Rockwell Hardness test is a hardness measurement based on the net increase in depth of impression as a load is applied. Hardness numbers have no units and are commonly given in the R, L, M, E and K scales. The higher the number in each of the scales means the harder the material.or instance, the progression from calcite to fluorite (from 3 to 4 on the Mohs scale) reflects an increase in hardness of approximately 25 percent; the progression from corundum to diamond, on the other hand (9 to 10 on the Mohs scale), reflects a hardness increase of more than 300 percent.