This publication identifies the ignition hazards involved in abrasive blasting of the exteriors of hydrocarbon storage tanks.that are in. service@ including @those whose vapor space contains a mixture that is flammable or that can become flammable when air is added. The term abrasive blasting is intended to include sandblasting and similar cleaning techniques that employ particles of abrasive materials jetted by compressed air. This publication provides operational guidelines for procedures that significantly reduce ignition risks during abrasive blasting of hydrocarbon tanks that may contain a flammable vapor space. It does not address other requirements for personnel safety and protective clothing@ such as eye protection.