Answer / carl_ellis

I totally disagree. Because NFPA 86 (2007) specifically
states that there is no need to impose requirements for
wiring methods appropriate for a hazardous (classified
area).

------- NFPA 86 (2007) ------------
A.4.1.3.3 Unless otherwise required by the local
environment, ovens and furnaces and the surrounding area
are not classified as a hazardous (classified) location.
The primary source of ignition associated with an oven
installation is the oven heating system or equipment or
materials heated. The presence of these ignition sources
precludes the need for imposing requirements for wiring
methods appropriate for a hazardous (classified) location.
Refer to Section 3.3 of NFPA497, Recommended Practice for
the Classification of Flammable Liquids, Gases, or Vapors
and of Hazardous (Classified) Locations for Electrical
Installations in Chemical Process Areas, and Section 3.3
------------ end ---------------

The 'gas train' or 'fuel train' is a pipe carrying fuel.
It is assumed that the fuel stays in the pipe until it gets
to the burner or is bypassed to an equally secure pilot
fuel line.

Control components in the pipeline typically need agency
approvals for conformance to failsafe conditions, but not
for explosion protection.

Carl Ellis
Measure First

Answer / swapnil s. dhamanse

First,you should read about NFPA 31 standard.My suggestion
is that you shoud used Eex type instrument on fuel
line,because most of fuel of boiler are flamable,so you
must used flame proof/explosion proof instrument.but,my
question is that why people think too to take decision
about about safety? boiler is highly hazardous area.I know
that outside the fuel line there is less posibilities of
flamable & explosive source but as per NFPA standard you
must use Eex type instruments.

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