AN EXPLOSION IS BROADLY DEFINED AS THE SUDDEN AND RAPID ESCAPE OF GASES FROM A CONFINED SPACE, ACCOMPANIED BY HIGH TEMPERATURES, VIOLENT SHOCK, AND LOUD NOISE. THREE BASIC TYPES OF EXPLOSIONS KNOWN TO MAN ARE MECHANICAL, CHEMICAL, AND ATOMIC. EXPLOSIVES NORMALLY ENCOUNTERED BY PUBLIC SAFETY PERSONNEL ARE CHEMICAL IN NATURE. IN ALL CHEMICAL EXPLOSIONS, CHANGES THAT OCCUR RESULT FROM COMBUSTION OR BURNING. AN EXPLOSION CAUSES BLAST PRESSURE, FRAGMENTATION, AND INCENDIARY OR THERMAL EFFECTS. THE PRIMARY REQUISITE OF A CHEMICAL EXPLOSIVE IS THAT IT CONTAIN ENOUGH OXYGEN TO INITIATE AND MAINTAIN EXTREMELY RAPID COMBUSTION. COMMON EXPLOSIVES ENCOUNTERED BY PUBLIC SAFETY PERSONNEL ARE LOW EXPLOSIVES (BLACK POWDER AND SMOKELESS POWDER), PRIMARY HIGH EXPLOSIVES (BLASTING CAPS AND DETONATING CORDS), SECONDARY HIGH EXPLOSIVE BOOSTERS, AND SECONDARY HIGH EXPLOSIVE MAIN CHARGES (DYNAMITE, AMMONIUM NITRATE, BLASTING AGENTS, FREE-RUNNING EXPLOSIVES, TWO-PART EXPLOSIVES, LIQUID EXPLOSIVES, MILITARY EXPLOSIVES AND IMPROVISED EXPLOSIVES). BLASTING ACCESSORIES, PRODUCTS OR DEVICES USED TO PREPARE, TEST, OR INITIATE EXPLOSIVE CHARGES, INCLUDE BLASTING CAP CRIMPERS, FUSE IGNITERS, POWDER IGNITERS, FIRING WIRE, BLASTING MACHINES, AND GALVANOMETERS. AN INDEX AND NUMEROUS ILLUSTRATIONS OF EXPLOSIVES AND BLASTING ACCESSORIES ARE INCLUDED. (DEP)