Varistors and suppressors (TVS-diodes) are well-known and widely-used in electronic equipment as components providing voltage surge protection. For very powerful but very short-lasting pulses of the nanosecond range, with steep raising edge (such as HEMP pulses), the suitability of varistors and TVSdiodes is questionable. Since the technical community did not reach any shared vision regarding this point, the author performed its own tests described below.