If you are talking about “heat resistance” and “camping table” in the same sentence, then you are likely worried about the open flames of a campfire, or the burner of a camp stove. It is a good thing to be worried about, however, most of these tables are made with materials that are designed to sustain significant heat.
Aluminum camping tables can handle a much higher heat without melting,    but they are not impervious to damage. HDPE camping tables will melt when high temperatures are applied, so it is best to not have them sitting beneath a direct heat source.