It is preferred that the carbon raiser used as an addition to electric melting furnaces be less than 0.3% volatiles content. Volatiles content can be provided on Material Certification from supplier of the carbon raiser. Petroleum Coke by-products and industrial graphite scraps with high volatiles content can cause porosity in castings. This volatiles requirement does not apply to organic charcoal carbon raisers such as charred coconut hulls.