The standard classifies and codifies a great number of external influences to which an electrical system may be subjected: presence of water, solid objects, risk of impacts, vibrations, presence of corrosive substances, etc.

These situations can affect electrical components with a variable intensity depending on the characteristics of the system: presence of water, for example, can be either some drops of water falling or total immersion.

The standard IEC 60529 (EN 60529) indicates, by means of the IP code, the degree of protection for electrical devices

against access to energised parts and against the entry of water and of foreign solid objects.
This standard does not consider the protection against the risk of explosion or environmental situations like humidity, corrosive vapours, moulds or insects.
The IP code is composed of 2 characteristic digits and can be expanded by an additional letter if the protection of persons against access to energised parts is greater than the one indicated by the first digit.
Another supplementary letter indicates additional information on the protection of material.

To see classification criteria of the IP code click here.

The standards EN 50102 defines the degree of protection against mechanical impacts indicated with the letters IK, followed by anumber. The following table indicates the impact values in joules corresponding to each code

IK code  impact energy  00  not protected  01  0,15 Joule  02  0,2 Joule  03  0,35 Joule  04  0,5 Joule  05  0,7 Joule  06  1 Joule  07  2 Joule  08  5 Joule  09  10 Joule