# The Electromagnetic Compatibility Regulations 2005, Regulation 4: Electromagnetic disturbance


In these Regulations, “electromagnetic disturbance” means, subject to paragraphs (2) to (6) below, any electromagnetic phenomenon which is liable to degrade the performance of relevant apparatus.
(1) Without prejudice to the generality of paragraph (1) above, the following phenomena shall be regarded as electromagnetic disturbance (being phenomena expressly stated to be such in Article 1.2 of the EMC Directive):—
(a) electromagnetic noise;
(b) unwanted signals; and
(c) changes in the propagation medium.
(2) Without prejudice to the generality of paragraph (1) above and in addition to the phenomena regarded as electromagnetic disturbance pursuant to paragraph (2) above, the phenomena and effects listed in Schedule 2 hereto may be regarded as electromagnetic disturbance.
(3) A signal or emission which is a necessary function, or consequence of the operation, of relevant apparatus shall not be taken to be electromagnetic disturbance if, in relation to that apparatus, that signal or emission is permitted, and does not exceed the limits specified, by—
(a) the applicable EMC standard;
(b) a condition of the technical report or technical certificate;
(c) where the apparatus is radiocommunication transmission apparatus—
(i) a condition of the EC type-examination certificate; or
(ii) a term, provision or limitation of—
(aa) a licence granted under section 1 of the 1949 Act; or
(bb) regulations made under that section; or
(d) where the apparatus is—
(i) radiocommunication transmission apparatus; or
(ii) apparatus other than wireless telegraphy apparatus which operates by emitting electromagnetic radiation in the radio frequency spectrum,
any relevant provisions of regulations made under section 10 of the 1949 Act concerning radio frequency spectrum planning.
(4) A nuclear electromagnetic pulse (“NEMP”) shall not be regarded as electromagnetic disturbance.
(5) Without prejudice to the generality of the foregoing provisions of this regulation, the performance of relevant apparatus shall be taken to be degraded if any of the following types of interference with its function occur—
(a) permanent, temporary or intermittent—
(i) total loss of function;
(ii) significant impairment of function; or
(b) where the apparatus is information storage or retrieval equipment, destruction or corruption of information stored thereby.

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Source: https://www.legislation.gov.uk/uksi/2005/281/regulation/4 (the official version)
Page: https://openlegislation.uk/electromagnetic-compatibility-regulations-2005/regulation-4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.