In a world increasingly dependent on electronic solutions, electromagnetic compatibility (EMC) has become an essential factor.

Electromagnetic compatibility is the ability of various electronic equipments work perfectly sharing the same environment, i.e. to ensure that an electrical signal generated by one does not interfere with others.

There are several international standards that regulate the tests required for any equipment that is certified for use in different countries where standards are mandatory.

As an example we can cite:

- CISPR 22 Information technology equipment - Radio disturbance characteristics - Limits and methods of measurement,

- CISPR 25 Vehicles, boats and internal combustion engines - Radio disturbance characteristics - Limits and methods of measurement for the protection of on-board receivers

- IEC 61000-6-3 ed2.0 Electromagnetic compatibility (EMC) - Part 6-3: Generic standards - Emission standard for residential, commercial and light-industrial environments

Besides these, several other standards, national and international should be applied.

One item common to all standards is the need for a controlled electromagnetic environment to perform the measurements prescribed by them.

The most common way to implement a test environment in EMC is the use of an electromagnetic shielding, where walls, ceiling and floor made of conductive material are attached, preventing electromagnetic energy  generated inside from spreading outside and vice versa.

Some tests need more than a simple electromagnetic shielding, they need an anechoic or semi-anechoic chamber, where RF absorption materials are applied to the walls, ceiling and floor.

The use of absorbing material is indicated to reduce signal reflections within the shielded room.