Colin Cameron’s presentation is on the new edition of IEC 60079-11 Intrinsically Safe Equipment Standard. Edition 6 of IEC 60079-11 was published in 2011. A review of the standard was started by the maintenance team in 2014.

After significant re-organisation, several thousand suggestions for changes, 11 full committee meetings spanning 34 days, 14 full committee Zoom meetings, 22 specific task groups, and thousands of man hours, the long-awaited 7th edition is into its final stages before publication. Publication is expected in 2022, although the final draft stage (FDIS) against which certification is normally accepted, is expected Q3 2021.

This paper presents the significant changes from the 6th Edition, of which there are many. Some are classed as “major technical” changes which essentially mean a tightening of the rules which can have a significant impact on existing equipment, and are usually the changes that are considered when considering the impact on existing equipment of changes to standards. However, there are also a large number of clarifications which define how Edition 6 should have been interpreted, but for many manufacturers this will be different to the way that their equipment was assessed and therefore these could also have a significant impact on existing equipment.

There are also new items in the standard, such as signal isolator components that can transmit at high data rates across a very thin insulator which present great opportunities for improved functionality of intrinsically safe equipment.

Level of Protection “ic” (intrinsic safety for Zone 2 / 22) has moved further from the old Ex “nL” and now explicitly includes some non-countable faults for thermal ignition compliance.

In addition to the technical content, there has been a significant re-organisation of the standard, and there have been some changes in terminology used. This paper will be of considerable interest to all manufacturers, designers and assessors of intrinsically safe equipment.

Colin Cameron

Colin Cameron is a founder and Managing Director of Mutech Limited, an electronics product design and manufacturing service company in the UK specialising in intrinsic safety and functional safety. Mutech was established in 1985 and has been designing and manufacturing intrinsically safe equipment for their clients since 1992. Colin is Convenor of TC31 maintenance team for IEC 60079-11 Intrinsically Safe Equipment standard, member of the maintenance team for IEC 60079-25 Intrinsically Safe Systems, Chairman of the UK National Committee for IECEx, member of UK national mirror committees for IEC/T31 and IEC/T31/SC31G Intrinsic Safety, Chairman of the Technical Committee for the Association of British Mining Equipment Companies.