Why the World's Emulsion Explosives Detonate on Glass Bubbles

Sensitization is a reliability business

An emulsion matrix without voids is a fertilizer, not an explosive. Detonation starts at hot-spots — microscopic gas pockets that collapse adiabatically under shock. The commercial question is not whether you can create voids, but whether the voids you created at the plant still exist at the borehole, at −40 °C, six months later.

Chemical gassing agents create voids that grow, coalesce and escape. Expanded perlite crushes under auger loads. Hollow glass microspheres hold a sealed, engineered void at a certified crush strength — the sensitization you dosed is the sensitization that detonates.

What blasters and plants actually specify

• Dosage: typically 0.2–0.5 wt% — small enough that even premium spheres barely move cost per tonne of explosive

• Density control: microsphere grade selection sets finished product density and therefore velocity of detonation

• Survival: spheres must withstand pumping and augering; 2,000–4,000 psi grades are the workhorses

• Chemistry: borosilicate glass is inert in ammonium-nitrate oxidizer matrices — no side reactions, no shelf-life surprises

The procurement angle

Explosives plants run continuous campaigns; a sensitizer stockout stops the line, and an inconsistent sensitizer stops it worse. Single-site producers with lot-level certification and multi-thousand-tonne headroom are the only supply structure that matches the industry's risk tolerance.

Request density-response curves for explosives grades (HGS-32/HGS-38) in standard emulsion matrices.