If this is the xPM style HART cards they do a hardened version.
Not sure on the ambient temp/humidity requirements of the C200 so I guess it depends what quality of enclosure you intend to use.
The footprint of the PM IO backplanes is pretty big tho.
The C200 I/O is much smaller and probably better suited to field mounting.
I know they do a Fieldbus module for the C200 tho havnt seen a HART one yet.
Most installs I've seen have been in an equipment room.
Zone 2 is pretty lenient on protection requirements so a purged cabinet would cover it.
