and just to add some useful information to this post.. Here is a nice document talking about heat dissipation/thermal management in electronic enclosures. Its a good starter read for the OP.
http://www.hoffmanonline.com/stream_document.aspx?rRID=233311&pRID=162534

 

As for "products" holding certifications for high ambients look at many motors, solar equipment, or any piece of equipment for a communication/telephone system (switches/routers/dslams,etc..) Often the equipment is stuck into little more than a box outside baking in the sun on top of a hill.

Heck I've even been part of some joke of an international test (IEC/EN/CE) where a thermal chamber was used.. BUT all the do is stick your product in there and simply turn it on so the power LED comes on or whatever (not force it to 100%, 50% or even 10% fully loaded). Then after x amount of hours at maximum "rated" temperature they open the doors and if the unit is still on its considered passed/approved.. That's just crap and proves virtually nothing there. Big difference in something just being on and something running at its maximum. They also do the cold side too which was neat..They can actually make it snow inside those thermal chambers.

I'm done.. I do this stuff all day long and don't need to argue with you about how it works..

Thank you for your reply/input. I respect it. It is all OK for me. Yes I remember, I have seen thermal rating tables for cables and large motors in books, as well different classes/categories of isolation. Some of these I have also encountered in real world. Normally there would be a thermal fuse anyway. And ratings for cables include a large safety margin.

It's maybe a misunderstanding- you were considering electrical appliances like for instance large motors, and I was thinking of "domestic electronic goods", like for instance a computer, or television. Sometimes these are allowed to reach high temperatures, to a degree over the years the PCB will detoriate (or at least some areas of the PCB).

The thing is, I think if you take cheap domestic goods to Africa, chances are they may fail from the heat prematurely.