A new summary on the iec protection against electric shock

The IEC publication 60364-4-41 “Electrical installations of buildings” fifth edition offers a layout rationalized of protective measures; protection under normal conditions is provided by basic protective provisions and protection under single fault conditions is provided by fault protective provisions. The author proposes a revision of a previous paper on “A summary of the IEC protection against electric shock” and refers also of the IEC protection measures for common grounding systems of HV/LV parts in TN system installations. For the electrical risk assessment, the paper suggests the analysis of the risk exposure in analogy with dynamical collisions problems. For generality and simplicity the standard IEC proposes a conventional approach for the safety design; it is responsibility of the designer to verify that in each installation the conventional safety conditions must be applied but also to perfect them to the specific actual situations.