The aim of this paper is to review and compare the response to the electromagnetic radiation of different structural or non-structural composites on absorption, reflections and re-reflection grades. The area of interest has been reduced to the carbon allotropy and conducting non-magnetic/magnetic fillers (inclusions, metallic powders, granular ferrites) in dielectric hosts characterized by existing mixing rules. The results could be grouped in distinctive ranges, SE ≤ 10 dB corresponding to a poor shielding, 10–30 dB describing an acceptable effectiveness and SE ≥ 30 dB exceeding the acceptable range for industrial and commercial applications of 20 dB.