scope:

This document defines statistical considerations for the evaluation of radio frequency emission of mass produced products.

Note 1 It is based on CISPR TR 16-4-3.

The reasons for such statistical considerations are:

a) that the abatement of interference aims that the majority of the products to be approved shall not cause interference;

b) that the CISPR limits should be suitable for the purpose of type approval of mass- produced products as well as approval of single-produced products;

c) that to ensure compliance of mass-produced products with the CISPR limits, statistical techniques have to be applied;

d) that it is important for international trade that the limits shall be interpreted in the same way in every country;

Therefore, this document specifies requirements and provides guidance based on statistical techniques. EMC compliance of mass-produced products with the requirements of this document are based on the application of statistical techniques that reassure the consumer, with an 80 % degree of confidence, that 80 % of the products of a type being investigated comply with the emission limits.

This document does not define limits or measuring methods. It can be used only after radio frequency emission measurements have been performed according to the applicable radio frequency emission standard.

Note 2 Clause 4 gives some general requirements on the interpretation of CISPR radio disturbance limits and specifies different methods, which can be used alternatively. Clause 5 gives some specific requirements for certain product groups.

Note 3 The 80 %/80 % rule protects the consumer from non-compliant products, but it says hardly anything about the manufacturer's risk, whether a type of products will be accepted during a second statistical evaluation. More information on the acceptance probability for a repeated measurement is given in CISPR 16-4-3.