Some sort of safety vest (slime or orange) preferably with the appropriate ICS color markings/colors

I find Pete's list with BLACK boots interesting, particularly in light that the Army (and I believe USMC) have offically moved over to the Tan desert type boots, and frankly, in a situtation like Haiti, the color probably doesn't matter

The "Must be part of some self sustaining infrastructure" is CRITICAL

Grabbing some sort of NIMS guide would probably be a "good thing" if he is not conversant in ICS/NIMS, as I'm going to guess that the situation will fairly rapidly fall into a "pseduo-NIMS" operation, as many of the folks going down there WILL be NIMS aware

BTW - Plug time. FEMA has some online courses which are kinda handy to have if you are ever at an incident

Look for ICS-100, ICS-200 and ICS-700