X-no-Archive:yes
There are hardened versions of various handheld RF or serial devices,
although I've seen even those tortured to death. But I would think that they
should be able to handle dirt, dust, and oil. Ones I worked with, some six
years ago, where essentially DOS PCs under the hood, although that was
anything but obvious. The names Trakker and Spectrum come to mind, although
at this point I don't even remember much of the detail. When you see workers
in a store inventorying the shelves, they are often using some such device.

Greg Stigers
http://www.cgiusa.com