class 2, division 2

[victor e]

I have roughed in 1 and 2 gang masonry boxes in a block wall. On the open face of box side is a class 2, division 2 rated area. Are my boxes considered in the area? Do they have to be changed? (impossible now) or are surface mount devices suitable? I've searched the NEC, and cannot get a direct answer for my question. Can anyone help me with this?

 

[Coyote]

I have roughed in 1 and 2 gang masonry boxes in a block wall. On the open face of box side is a class 2, division 2 rated area. Are my boxes considered in the area? Do they have to be changed? (impossible now) or are surface mount devices suitable? I've searched the NEC, and cannot get a direct answer for my question. Can anyone help me with this?

I would say they are not allowed if they are in the CL II Div II area.
502.10 (B) (4) 2008 NEC

 

[victor e]

would the inside of a block wall- encased in cement be considered dust-tight?

 

[kwired]

would the inside of a block wall- encased in cement be considered dust-tight?

Are the block walls filled with concrete, and if not is the box within the wall subject to the class 2 environment?

Whatever covers the flush box opening needs to be dust tight.

 

[Coyote]

would the inside of a block wall- encased in cement be considered dust-tight?

If the box is not listed CL II Div II it is not dust tight.

 

[rbalex]

If the box is not listed CL II Div II it is not dust tight.

This is not correct. See the last line in the FPN for Table 110.20. Dusttight applies to Enclosure Types 3, 3S, 3SX, 3X, 5, 12, 12K, and 13.

 

[Coyote]

This is not correct. See the last line in the FPN for Table 110.20. Dusttight applies to Enclosure Types 3, 3S, 3SX, 3X, 5, 12, 12K, and 13.

Bob, thanks. I stand corrected I was thinking of Cl II Div I G. E Locations

 

[victor e]

The wall is encased with concrete.