Is Isolated Barrier Necessary for Equipment with Intrinsic Safety Certification Ex e ib mb I IC T6 G

[John668]

The equipment holds the certification Ex e ib mb I IC T6 Gb, where "ib" signifies intrinsic safety. This certification confirms that the equipment is specifically engineered to restrict electrical energy, prevent the occurrence of sparks, and minimize excessive heat that could potentially ignite an explosive environment. Given this "ib" certification, is it accurate to state that isolated barriers are not necessary since the equipment already meets the required safety standards?

 

[FacEngrPE]

The instructions for this device will include a "certification Drawing" which will explain if barriers are needed, if there is a circuit length limit, and possible other certification constraints.

Given this "ib" certification, is it accurate to state that isolated barriers are not necessary since the equipment already meets the required safety standards?

is an incorrect statement. If the Certification Drawing requires a barrier, then one is required,

 

[waross]

If by isolated barrier you mean conduit seals or cable seals, these may be required to prevent the migration of gas outside the explosive zone.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[FacEngrPE]

Looks like a picture is needed. I have attached a copy of a certification book for a device that is listed under FM, UL, and CE rules as appropriate to use in intrinsically safe (Limited Energy) circuits .

The requirement for ITL type certified conduit seals or cable glands applies, but is not part of the intrinsic safety section (504) of the national electric code.
Similar diagrams apply for equipment type certified for application under ATEX Directives.

 

[resqcapt19]

If that is the control diagram for the instrument you are using, you are required to make the installation in accordance with that diagram. 504.10(A).
If that is not the diagram for your instrument, you need the one for the instrument being installed. Remember it is not only the field instrument that could ignite a flammable gas, it is also the possibility of power on the circuit that connects to the field instrument.