Class 1 Div 1 Location

[inspector 102]

In a room that has a floor area of 3200 sf, and an area around the equipment of a 15 foot circle that is classified as C1D1, Does the remaining portion of the room require similar protection. Where do I find the section describing C1D1 limits. I do not deal with this enough to be comfortable making a decision. Local industry has asked me to look into this for their safety compliance. Any assistance appreciated.

 

[tryinghard]

C1D1 is usually a 20' radius around the classified item. Its also 18" plane adjacent to it. So electrical can be outside the C1D1 if it is 20" above or alongside, see Figure 514.3 for a visual (of 514.3(B)(1)).

 

[weressl]

In a room that has a floor area of 3200 sf, and an area around the equipment of a 15 foot circle that is classified as C1D1, Does the remaining portion of the room require similar protection. Where do I find the section describing C1D1 limits. I do not deal with this enough to be comfortable making a decision. Local industry has asked me to look into this for their safety compliance. Any assistance appreciated.

Give them the Obama answer: It's above my paygrade.

Seriously, this descision needs a lot more informatin than this. It is very difficult to have an inside area classified as anything less than Div. 1 for the entire area UNLESS there is adequate ventilation provided. Engineers, operations and safety people usually required to sit together and decide the answers based on the NFPA requirements.