Magnetic method: Battery operated magnetic device that can measure the depth of reinforcement cover in concrete and detect the position of reinforcement bar are now available. The apparatus is known as cover meter. This can use for measuring the cover given in the lightly reinforced section.

Electrical method: Recently some electrical method employ for determine the moisture content of harden concrete. Tracing of moisture permeation through concrete and determining the thickness of concrete pavement. The accurate determination of moisture content of harden concrete is required in connecting with creep shrinkage and thermal conductivity study the fact that dielectric properties of harden concrete change with changes in moisture content is made use of in this method.