hazardous locations C1D1 and C1D2 right next to each other

[diazcolocho]

Dear mr. Mike holt

I really enjoy Reading your nec articles all the time ever since I graduated from university
And would like to address a particular question to you in regards to your most recent article
Understanding requirements for haz locations:

1. If we were to have a situation very similar to the one depicted on fig 2 of your article

Whereby you have a C1D1 area right next to a C1D2 area, would you consider using
C1D1 lighting fixtures for that area and C1D2 fixtures for the other one even though
They are right next to each other? Why? Is this sustained in the nec or not?

1. What is your best recommendation as I am in the middle of one exact situation for

Paint company where they will store the paint and on the other one mix and prepare
The paint

Thanks and hoping to hearing from you soon,

Ing. Juan Diaz Colocho, MSEE, PE
DIAZ COLOCHO HERMANOS
CARIBE HOBBY CENTER
ASESORIA Y TECNOLOGIA EN ILUMINACION (IESNA CERTIFIED)
TEL 503-22981005 / 70053980

 

[rbalex]

Welcome to the forums.

I believe this is the newsletter you were referring to but I couldn't find figure 2. However, if I understand your question, it isn't critical.

In "open air" there will always be a Division 2 envelope around Division 1. See Section 500.5(B)(2)(3).

Equipment may be installed per the area classification it is located in. Even if the Division 2 equipment is immediately next to an "imaginary" boundary, it would still be acceptable. (You have to draw the line somewhere.)

Luminaires (fixtures) do have a few special cautions, the primary (but not only) one being operating temperatures. See Section 501.130.

 

[MRKN]

I as well have no idea what figure you're referencing.

With that said, it all comes down to presence of a vapor-tight barrier. In general a non-vaportight barrier will have no effect on the radius of the boundary, whereas a vaportight barrier would. The question then becomes if you have an enclosed area .. as this will prevent dispersion and allow accumulation.

See Figures 2-5 in API RP-500, one of these will be applicable for your question.

 

[Dale001289]

Dear mr. Mike holt

I really enjoy Reading your nec articles all the time ever since I graduated from university
And would like to address a particular question to you in regards to your most recent article
Understanding requirements for haz locations:

1. If we were to have a situation very similar to the one depicted on fig 2 of your article

Whereby you have a C1D1 area right next to a C1D2 area, would you consider using
C1D1 lighting fixtures for that area and C1D2 fixtures for the other one even though
They are right next to each other? Why? Is this sustained in the nec or not?

1. What is your best recommendation as I am in the middle of one exact situation for

Paint company where they will store the paint and on the other one mix and prepare
The paint

Thanks and hoping to hearing from you soon,

Ing. Juan Diaz Colocho, MSEE, PE
DIAZ COLOCHO HERMANOS
CARIBE HOBBY CENTER
ASESORIA Y TECNOLOGIA EN ILUMINACION (IESNA CERTIFIED)
TEL 503-22981005 / 70053980

Just FYI -heavy industry these days is leaning heavily toward LED type lighting fixtures. Unlike HID (high intensity discharge) luminaires with ballasts etc, surface temperature (T-rating) for LED lighting is more 'friendly'. Crouse-Hinds has a nice Class I, Division 1 LED luminaire - 'HAZARD*GARD EVLL' that you might want to investigate.

 

[MRKN]

Yes, they are also justified based on cost savings and rebate incentives alone.

 

[rbalex]

As I understood his question, he was asking if a Division 2 location adjoining or abutting a Division 1 location (with or without a vaportight barrier) required Division 1 luminaires in Division 2. (More or less API RP 500 Figure 2, or maybe 4 or 5) The answer is no, equipment only needs to be suitable for the Division it's located in.

I have no problem with LEDs and can recommend them too. I actually helped an "unnamed" manufacturer evaluate their line and can basically endorse almost any listed major. (I don't know all of them, of course)