Natural, additive-free wood charcoal and ash can be beneficially reused in many ways.  For more information, click here If reusing charcoal ash, always make sure that the material is completely cooled before doing anything else with it.

Charcoal briquettes contain potentially dangerous chemicals that prevent them and their ash from being safely reused.  Unused charcoal briquettes can be disposed of in the regular trash. 

To prevent fire hazard, used charcoal, charcoal briquettes and charcoal ash must be completely cooled and wrapped in aluminum foil or placed in a sealed metal can before being disposed of in the trash.