Define Misfire.

Define Misfire.

• A. When explosive charge detonates unexpectedly
• B. When explosive charge fails to detonate
• C. When the blast is delayed
• D. During misfire the charge self-detonates early

Answer: (B)

Misfire means the explosive charge does not detonate as planned. In blasting practice, this means the charge in the borehole remains unignited or fails to produce the expected explosive effect. It’s different from a blast that goes off later than scheduled (delayed detonation) or from a detonation that happens unexpectedly or prematurely. A misfire does not occur because the charge detonates early; that would be a premature detonation, not a misfire. Because a misfire can leave an unexploded charge, it requires strict safety steps—secure the area, wait a prescribed time, and follow proper procedures under supervision before attempting reinitiation.

Misfire means the explosive charge does not detonate as planned. In blasting practice, this means the charge in the borehole remains unignited or fails to produce the expected explosive effect. It’s different from a blast that goes off later than scheduled (delayed detonation) or from a detonation that happens unexpectedly or prematurely. A misfire does not occur because the charge detonates early; that would be a premature detonation, not a misfire. Because a misfire can leave an unexploded charge, it requires strict safety steps—secure the area, wait a prescribed time, and follow proper procedures under supervision before attempting reinitiation.