I will try and keep this as simple as possible. I have a bus washing compound with fuel dispensing accomodations. In the pit under the dispenser, two conduits come in, one for 120 volt for the dispenser and one for the card reader cable mounted between 2 dispensers. This conduit leaves the dispenser pit and goes to the card reader. THe 120 volt conduit has all the appropriate seal offs. The other conduit does not have seal offs. I feel this conduit requires one also if not for the conductor's, for the conduit itself possibly getting hazardous gases in it, but am I wrong according to
504 and who determines this to be intrinsically safe??

what type of fuel

Regular gas and diesel fuel.There is one diesel fuel pump and 2 gas dispensers. The conduits I was referring to were the gas

Paul, the equipment mounted in the hazardous area must first be approved for use in an intrinsically safe system. Usually here in the US that is already done by UL, IF it is approved as such.

Intrinsically safe barriers and equipment must also be wired according to an approved drawing.

There is a 97% chance that you are right, and seal off is required. If it was intrinsically safe, you would be hearing that feedback from the engineer and seeing a diagram on that, along with the plans.

I agree with Nick. I would need to see proper documentation as stipulated in 500.4(C) / 504.10(A) of the NEC.

I would say a seal off in the dispensor area for this cable is needed.art.514.9 (a)