A blasting condition where the explosive charge is too large or placed too close to the free face of the rock. Instead of fracturing the rock efficiently, the excess energy blows out violently, causing excessive flyrock, airblast, and a high risk of igniting coal dust or methane in underground settings.
Heard on the job
That last shot was underburdened and blew half the face across the drift instead of dropping it in place.
Insider tip
In coal mines, an underburdened shot is a major safety hazard because the blown-out flame can easily trigger a secondary dust explosion.