International Standards and Conformity Assessment for all electrical, electronic and related technologies



Reference EN 60079-31:2009
Title Explosive atmospheres - Part 31: Equipment dust ignition protection by enclosure "t"
Project Number 21153
Abstract/Scope IEC 60079-31:2008 is applicable to electrical equipment protected by enclosure and surface temperature limitation for use in explosive dust atmospheres. It specifies requirements for design, construction and testing of electrical equipment. This standard supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of this standard shall take precedence. This first edition of IEC 60079-31 has been developed from the first edition of IEC 61241-1 (2004) which it now cancels and supersedes. The significant changes with respect to the previous edition are: - Title changed to Equipment dust ignition protection by enclosure 't' - Combination and rationalisation of practice A and B into a single practice, and some constructional requirements that may have applied to only one practice now apply to all enclosures - Introduction of three levels of protection, 'ta', 'tb' and 'tc' - Defined test voltage ranges and overload conditions for thermal tests - Introduction of a pressure test prior to the IP test - Restrictions on power and voltage levels for level of protection 'ta' - Introduction of a variant of the IP6X test for level of protection 'ta' - Compulsory dust layer thermal test for protection level 'ta' by surrounding the enclosure with dust to a depth of at least 500 mm on all available surfaces. The contents of the corrigendum of March 2009 have been included in this copy.


Current Stage code 6060
Current Stage code date 2009-12-04
Current Stage code deadline 2010-07-01
Deadline date for vote  


Directive(s) ATEX (94/9/EC)
Order Voucher  


IEC Technical Body IEC/TC 31
Reference Document IEC 60079-31:2008 (EQV) + corrigendum Mar. 2009 (EQV)
ICS 29.260.20 - Electrical apparatus for explosive atmospheres
Keywords Explosive atmospheres; Dust; Ignition protection
Note Supersedes EN 61241-1:2004 + corr. Dec. 2006
Special National Condition(s)  


Categories - Aspects
Product Life Cycle


Deadline Date
6060 2009-12-04 2010-07-01 export to doc file  EN  FR  DE
5099 2009-10-01 2009-12-01  
5061 2009-08-27 2009-10-01  
5060 2008-10-21 2008-11-21 export to doc file  EN
5020 2008-08-15 2008-10-17  
3090 2007-08-10 2008-08-31  
5060 2007-07-30 2007-08-09 export to doc file  EN
5020 2007-02-23 2007-07-27  
1090 2007-02-20 2007-02-23  

Implementation Dates

date of Ratification (DOR) (1) 2009-10-01
date of Availability (DAV) (2) 2009-12-04
date of Announcement (DOA) (3) 2010-01-01
date of Publication (DOP) (4) 2010-07-01
date of Withdrawal (DOW) (5) 2012-10-01


Supersedes EN 61241-1:2004
EN 61241-1:2004/corrigendum Dec. 2006
Superseded by FprEN 60079-31:2013
Normative reference (6) ISO 965-1:1998
ISO 965-3:1998
EN 60034-1:2004
EN 60079-0:2009
EN 60079-7:2007
EN 60127-1:2006
EN 60691:2003

(1) Date of ratification (dor) date when the Technical Board notes the approval of an EN (and HD for CENELEC), from which time the standard may be said to be approved

(2) Date of availability (dav) date when the definitive text in the official language versions of an approved CEN/CENELEC publication is distributed by the Central Secretariat

(3) Date of announcement (doa) latest date by which the existence of an EN (and HD for CENELEC), a TS or a CWA has to be announced at national level

(4) Date of publication (dop) latest date by which an EN has to be implemented at national level by publication of an identical national standard or by endorsement

(5) Date of withdrawal (dow) latest date by which national standards conflicting with an EN (and HD for CENELEC) have to be withdrawn

(6) This list of normative references is purely indicative. The only official list of normative reference is the list of the published standard.