Allowed Div 1 Protection

[Juason]

Hello everyone. I recently ran across an example of what I believe to be a flameproof design utilizing encapsulation to provide Class 1 Div 1 product certification. Without revealing the product, the certification was specified as:

CSA Ex II 2G EEx md IIC T5
Cl 1; Zone 1; Ex md IIC T4
Cl I; Div 1; Grps. A, B, C, D; T4

The md describes how encapsulation and flameproofing are used as the protection mechanisms.

The 60079 standard appears to list only Pressurized "x", Intrinsically safe "ia/ib" or Explosion proof designs, as viable protection mechanisms in Div 1 areas. Encapsulation and Flameproof would be acceptable only for Zone 1 locations. Zone 1 certified products cannot be used in Div 1 locations specifically because of this difference in allowable protection mechanisms.

Am I correct in my assessment of this, or are they just not listing some alternate protection method by which Div 1 certification was reached?

Thanks!

 

[rbalex]

Hello everyone. I recently ran across an example of what I believe to be a flameproof design utilizing encapsulation to provide Class 1 Div 1 product certification. Without revealing the product, the certification was specified as:

CSA Ex II 2G EEx md IIC T5
Cl 1; Zone 1; Ex md IIC T4
Cl I; Div 1; Grps. A, B, C, D; T4

The md describes how encapsulation and flameproofing are used as the protection mechanisms.

The 60079 standard appears to list only Pressurized "x", Intrinsically safe "ia/ib" or Explosion proof designs, as viable protection mechanisms in Div 1 areas. Encapsulation and Flameproof would be acceptable only for Zone 1 locations. Zone 1 certified products cannot be used in Div 1 locations specifically because of this difference in allowable protection mechanisms.

Am I correct in my assessment of this, or are they just not listing some alternate protection method by which Div 1 certification was reached?

Thanks!

With respect to the NEC, only the third line (Cl I; Div 1; Grps. A, B, C, D; T4) is relevant. Depending on the certification standard and the agency that applied it, the product is suitable for Class I, Division 1.

Notes:

• "Flameproof" does not apply to "Division" certified products; while it is somewhat analogous to "Explosionproof", it is strictly a "Zone" rating.
• IEC Standard 60079 is also irrelevant Division ratings.
• The marking also would make the product unsuitable for NEC "Zones" since it must be certified as "AEx" rather than "Ex" or "EEx." See Section 505.9(C)(2).
• In general "Hermetically Sealed" is the Division analog for Zone "encapsulated" (Protection Technique "m")