Abstract: The glass pane of an emergency equipment access panel is replaced by tempered glass as opposed to conventional annealed glass panels of the type available in the prior art. Tempering places the surfaces of the glass in a higher degree of compression while balancing tensile forces are confined to the interior. Because of the high degree of permanent stress induced in the glass by tempering, if any portion of the tempered glass is weakened, such as by cracking even an edge thereof, the entire structure virtually disintegrates into a large plurality of small, relatively harmless pieces, leaving no significant size shards of glass that might otherwise injure one's hand or arm reaching through the shattered glass to gain access to the interior of a cabinet for example. An edge breaking device provides a simple and convenient means for exploiting the high stresses built into tempered glass and produces the virtual disintegration of the glass panel even though only an edge portion thereof has been fractured.