Befähigungsprüfung Sprengungsunternehmen Practice Questions - Befähigungsprüfung Sprengungsunternehmen (Austria) Exam

Black powder deflagrates at subsonic velocities (~300 to 500 m/s), producing expanding gas volume that gently heaves and splits intact stone blocks along natural bedding planes without creating shattering micro-fissures. Black powder has a higher detonation velocity than pure TNT. Black powder detonates at about 7,000 m/s, pulverizing the stone into fine aggregate. Black powder is simply the cheapest explosive per kilogram, which is the sole reason for its selection.