Protection concepts North America and Canada
The tables below list the types of protection methods and basic concepts of protection according to US and Canadian standards for electrical equipment that is to be operated or installed in hazardous areas. The matrix is constructed to enable the fast cross referencing of protection concepts for classes and divisions, or classes and zones including the applicable US and Canadian standards.
For definitions of hazardous zones, please see Hazardous areas according to ATEX, IECEx zones and North American Classes and Divisions section.
Similar matrix of protection concepts can also be found for ATEX and IECEx.
Electrical equipment for flammable gases, vapours and mist | ||||||||||
US code | CAN code | Type of protection | Basic concept of protection | Class I Div | Class I Zone |
US Standard | CA Standard | |||
1 | 2 | 0 | 1 | 2 | ||||||
AEx e | Ex e | Increased safety | No arcs, sparks or hot surfaces | • |
• |
ISA 60079-7 | CSA E60079-7 | |||
(NI) | (NI) | Non-incendive | • |
ISA 12.12.01 / FM 3611 | C22.2 No. 213 | |||||
AEx nA | Ex nA | Non-sparking | • |
ISA 60079-15 | CSA E60079-15 | |||||
(XP) | (XP) | Explosion proof | Contain the explosion and extinguish the flame |
• |
• |
UL 1203 / FM 3615 | C22.2 No. 30 | |||
AEx d | Ex d | Flame proof | • |
• |
ISA 60079-1 / UL 1203 / FM 3615 | CSA 60079-1 | ||||
AEx q | Ex q | Powder filled | • |
• |
ISA 60079-5 | CSA E60079-5 | ||||
AEx nC | Ex nC | Enclosed break | • |
ISA 60079-15 | CSA E60079-15 | |||||
(IS) | (IS) | Intrinsic safety | Limit energy of sparks and surface temperature | • |
• |
UL 913 / FM 3610 | 22.3 No. 157 | |||
AEx ia | EX ia | • |
• |
• |
ISA 60079-11 / FM 3616 | CSA E60079-11 | ||||
AEx ib | EX ib | • |
• |
ISA 60079-15 | CSA E60079-15 | |||||
AEx nL | EX nL | Limited energy | • |
ISA 60079-15 | CSA E60079-11 | |||||
Type X | Type X | Pressurised | Keep flammable gas out | • |
• |
NFPA 496 (FM 3620) | NFPA 496 | |||
Type Y | Type Y | • |
• |
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Type Z | Type Z | • |
||||||||
AEx px | Ex px | • | • |
ISA 60079-2 | CSA E60079-2 | |||||
AEx py | Ex py | • |
• |
|||||||
AEx pz | Ex pz | • |
||||||||
AEx nR | Ex nR | Restricted breathing | • |
ISA 60079-15 | CSA E60079-15 | |||||
AEx m | Ex m | Encapsulated | • | • | ISA 60079-18 | CSA E60079-18 | ||||
AEx ma | N/A | • | • | • | N/A | |||||
AEx mb | • | • | ||||||||
AEx o | Ex o | Oil immersion | • | • | ISA 60079-6 | CSA E60079-6 |
Electrical equipment for combustible dust | |||||||||||
US code | CAN code | Type of protection | Basic concept of protection |
Class II Div | Class III Div 1&2 |
Class II Zone | US Standard | CA Standard | |||
1 | 2 | 0 | 20 | 21 | 22 | ||||||
(DIP) | (DIP) | Dust ignition protection | Keep combustible dust out | • |
• |
• |
UL 1203 / FM 3616 | CSA C22.2 No. 25 | |||
(NI) | (NI) | Dust protected | • | • | ISA 12.12.01 / FM 3611 | CSA C22.2 No. 25 | |||||
AEx ta | Ex ta | Protection by enclosure | • | • | • | ISA 60079-31 | CSA C22.2 No. 60079-31 | ||||
AEx tb | Ex tb | • | • | ||||||||
AEx tc | Ex tc | • |
|||||||||
N/A | N/A | Fibre & flying protection | • | UL 1203 / ISA 12.12.01 | CSA C22.2 No. 25 | ||||||
AEx maD | N/A | Encapsulation | • | • | • | ISA 60079-18 | N/A | ||||
AEx mbD | • | • | |||||||||
(PX) | (PX) | Pressurisation | • | • | • | NFPA 496 (FM 3620) | NFPA 496 | ||||
(PY) | (PY) | • | • | • | |||||||
(PZ) | (PZ) | • | • | ||||||||
AEx pD | N/A | • | ISA 61241-2 | N/A | |||||||
(IS) | (IS) | Intrinsic safety | Limit energy of sparks and surface temperature |
• | • | • | UL 913 / FM 3610 | CSA C22.2 No. 157 | |||
AEx iaD | N/A | • | • | • | ISA 60079-11 | N/A | |||||
AEx ibD | • | • |
Guide for Hazardous Areas
- Hazardous areas according to ATEX, IECEx zones and North American Classes and Divisions
- Gas & dust groups and temperature classifications
- Apparatus groups and common flammable gases, vapours and dust types
- Protection concepts ATEX and IECEx
- Protection concepts North America and Canada
- IP ratings and NEMA enclosure types
- Cable gland selection
- Typical equipment marking and references
E2S offers an extensive range of intrinsically safe, explosion & flameproof and non-sparking audible and visual signals, PA loudspeakers and manual call points for hazardous areas.