Hi Jim,
I did not take any extra steps to protect the AJA from heat or dust. I just used my usual cautions, got out of the sun when possible, powered down often (more to conserve power than heat concerns) The unit got very,very hot, but I had no issues whatsoever. It was in a Portabrace and I wore it on my waist on my hip and small of my back. I could actually feel the heat from the unit on my back, not especially welcome in the heat of equatorial Africa!
I was also comforted in the event of heat related breakdown, or drive errors that I had tape rolling in the camera as my backup.
Ron