Preface:

This is the third edition of CAN/CSA-C22.2 No. 60079-15, Explosive atmospheres — Part 15: Equipment protection by type of protection "n", which is an adoption, with Canadian deviations, of the identically titled IEC (International Electrotechnical Commission) Standard 60079-15 (fifth edition, 2017-12). It supersedes the previous edition published in 2016 as CAN/CSA-C22.2 No. 60079-15 (adopted IEC 60079-15:2010). It is one in a series of Standards issued by CSA Group under Part II of the Canadian Electrical Code.

For brevity, this Standard will be referred to as "CAN/CSA-C22.2 No. 60079-15" throughout.

This Standard is intended to be used in conjunction with CAN/CSA-C22.2 No. 60079-0, Explosive atmospheres — Part 0: Equipment — General requirements.

Changes to this edition include the changes to the fifth edition of the IEC Standard:
a) Enclosed break devices "nC" are now designated as "dc" and the requirements are located in CAN/CSA-C22.2 No. 60079-1.
b) Type of protection "nA" is now designated as type of protection "ec", and the requirements for "ec" equipment are located in CAN/CSA-C22.2 No. 60079-7.
c) Test time for the preparation of non-incendive component samples has been specified.
d) Additional documentation requirements for seals and gaskets have been added.
e) As the pressure inside an enclosure fitted with fans can be affected by the operation of the fan, it is now specified that the restricted breathing test is conducted with fans operating and stationary.
f) The limitations from CAN/CSA-C22.2 No. 60079-15, first edition, were added.

This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group.

Scope:

This part of IEC 60079 specifies requirements for the construction, testing and marking for Group II electrical equipment with type of protection "n" which includes; sealed devices "nC", hermetically sealed devices "nC", non-incendive components "nC" and restricted breathing enclosures "nR" intended for use in explosive gas atmospheres. This part of IEC 60079 applies to electrical equipment where the rated input voltage does not exceed 15 kV r.m.s. AC or DC including where the internal working voltages of the Ex product exceeds 15 kV, for example starters for HID luminaires.