What country and what industry - i.e. which codes and standards apply? Offshore in the North Sea is different than a refinery in Texas.
What do you mean by instrument cable? Does this mean 4-20 mAdc or TIA 232 or thermocouple? Intrinsically safe? Copper Ethernet?
There are lots of ways to cover the explosion proof issue. What is the area classification? Marine industry likes different stuff than onshore industry. I am used to conduit. Others may use MI cable or armored cable, etc.
Tell us more.
For 4-20 mAdc home run cables I prefer bundles with individually shielded twisted pairs rated 600 V (another controversy) rated 90 degree C and for wet locations. What if it is on a heater stack? OK, higher than 90 degree C.
John