CISPR is acronym for the French words for the International Special Committee on Radio Interference.  “Comité International Spécial des Perturbations Radioélectiques”.  CISPR is a special committee of the International Electrotechnical Committee (IEC).

CISPR is organized into a number of subcommittees.  These cover a variety of subjects.

CISPR SC A, Radio-interference measurements and statistical methods, “owns” standards covering the test equipment, test methods and other related subjects within CISPR.  These standards are often referenced by other standards written within CISPR.

CISPR SC B, Interference relating to industrial, scientific and medical radio-frequency apparatus, to other (heavy) industrial equipment, to overhead power lines, to high voltage equipment and to electric traction, deals with product family standards in its area of responsibility.

CISPR SC D, Electromagnetic disturbances related to electric/electronic equipment on vehicles and internal combustion engine powered devices, deals with product family standards for vehicles.

CISPR SC F, Interference relating to household appliances, tools, lighting equipment and similar apparatus, deals with product family standards for household appliances, etc.

CISPR SC H, Limits for the protection of radio services, is responsible for developing limits for emissions.  These limits may be used by other subcommittees.

CISPR SC I, Electromagnetic compatibility of information technology equipment, multimedia equipment and receivers, deals with product family standards for the subject equipment.  SC I was formed in 2001 by merging the old SC E (Broadcast receivers) and SC G (Information Technology Equipment).  This was brought about by the convergence of the two technologies in the form of digital television receivers.

CISPR S is the steering committee of CISPR.  Membership is basically comprised of the leadership of CISPR.  The Chair, Vice Chair, Secretary of CISPR and the Chairs of the subcommittees.

Subcommittees may have Working Groups or Maintenance Teams under them.  For example, SC I presently has two Working Groups.  WG2 deals with emissions standards.  WG4 deals with immunity standards.  As the older standards have been frozen, this means that WG2 is responsible for the maintenance and updating of CISPR 32 and WG4 is responsible for generating CISPR 35.

Under new IEC rules, leadership positions in the IEC (and, therefore, CISPR) are limited to a 6 year term, renewable once for an addition 3 years.  The result of this is that most leadership positions in CISPR and its subcommittees will change on November 1 of this year.  CISPR SC I has be lead since its formation in 2001 by Martin Wright of the UK.  Effective November 1 the new Chair will be the author of this blog, Ghery S. Pettit of the US.  Martin has done a great job over the past 15 years and I will be challenged to do as fine a job.

What documents are written in order to create a new standard or amend a standard?

Once the work is approved (which requires additional documents), a Working Group or Maintenance Team spends time generating a new document.  This may go out to the national committees as a Document for Comment (DC) if the work is still early, or as a Committee Draft (CD).  These are documents which request comments from the national committees.  These are not voting documents.

After the comment deadline has passed these comments are published as a Compilation of Comments (CC).  The WG or MT then goes through the comments and decides on what action, if any, will be taken on the comments.  Multiple CDs may be circulated before comments become few and it is felt that a vote may be successful.

The first voting document is a Committee Draft for Vote (CDV).  This document contains the proposed standard in what is hoped will be its final form.  The national committees vote on accepting or rejecting this document.  “Yes” votes do not require comment, “No” votes must be justified with comments.  The comments may be as simple as “No, we don’t support this standard” to detailed comments on what that national committee feels should be changed to make the standard acceptable to them.  If a CDV receives unanimous approval it may be published as an International Standard without further vote.

If the CDV is accepted with less than a unanimous vote the WG or MT will be directed by the subcommittee to address any comments that it feels would improve the standard and then circulate a Final Draft International Standards (FDIS) for vote.  The same requirements for voting apply as did for a CDV.  If this document is accepted the standard is then published by the IEC.  If it does not pass then the subcommittee must decide on the next action to take.

What constitutes a passing vote?

There are two types of members in the IEC.  And these member types vary between subcommittees.  A country may be a Participating (P) member or an Observer (O) member.  For a document to be accepted there are two criteria applied.

First, at least 67% of the P members voting must approve the document.  Less than 67% and the document is rejected.

Section, at least 75% of all votes (P and O) must be in favor or approving the document.  Less than 75% and the document is rejected.

Both criteria must be met in order for a document to be accepted.

If this seems excessive for approving a standard, remember that any national committee can vote “Yes” without further comment.  Even if they haven’t taken an active part in writing the standard.  A “No” vote requires comments and it, therefore, more difficult to write if the national committee has not taken an active part in writing the standard.

I hope this helps dispel some of the mystery behind where CISPR standards come from.  If you have questions, please feel free to e-mail me at Ghery@PettitEMCConsulting.com and I’ll be happy to answer them.