I am for the first time working in a class 1 div 2 area. B/C/D. I have to install in a room 5 mass flow meters that themselves are rated correctly. However, they have an D shell connection where 2 of the wires in this cable are for 24vdc power supply(supplied), and am using 2 of the other wires for control by a DCS, 4-20ma. These meters have to be visual of course so bottle flow rate can be monitored. I am thinking running rigid conduit to 5 indivual boxes mounting a 120V recepticle in each to make use of the plug in power supply supplied with the unit. Would a stainless 4x box be sufficient here as long as I seal the inputs? I was thinking of mounting the MFM on individual 'shelves' and running the cable into the box mentioned. Any thoughts? Anyone do anything like this before? These measure flow by the way of N2, Ar, CO2, CO and H2. Thanks for any responses.