What material should I wrap my passport with in order to retain the heat when going on an overseas skiing trip? Outdoor temperatures may drop to 0F or even lower. Even if I put it in the inner pockets of my ski jacket theres still the possibility of exposing it to below freezing temp and damaging the electronic chip inside. Will aluminum foil work? I stay in a mixed dor so I must bring along with me all my valuables.
Same thing goes tom y small digital camera.
No need to wrap your passport. As far as I am aware all the chips in passports are passive/RFIDs - you could stick your passport in the freezer or bury it in ice and snow and would not damage it.
For the camera, find a way carry it close to your body. Most cameras actually work pretty well even at low temperatures albeit with worse battery life (although 0F is pushing it for consumer point & shoot cameras). The main issue is condensation (from rapid temperature changes) on the lens and inside the camera body, battery compartment, etc. Carry it close to your body, maybe in a neoprene cover and you should be fine.