Sunday, 28 February 2021, 4:59 PM
Site: Blast Training International
Course: Blast Training International (BTI)
Glossary: Glossary
H

High Temperature Blasting

Blasting which is carried out in material at a temperature of 100°C or greater.

Hit Mark

Point of impact on receptor from donor, typically related to shock tube.

hitmark

Hit mark from properly functioning low energy surface delay on shock tube.

HMX

Cyclotetramethylene tetranitramine, a high explosive used in the core loading of shock / signal tube and in high temperature applications.

HMX, also called octogen, is a powerful and relatively insensitive nitroamine high explosive, chemically related to RDX

The molecular structure of HMX consists of an eight-membered ring of alternating carbon and nitrogen atoms, with a nitro group attached to each nitrogen atom. Because of its high molecular weight, it is one of the most potent chemical explosives manufactured

HMX Structure

HNS

Hexanitrostilbene (HNS), also called JD-X, is a heat resistant high explosive developed at the Naval Ordnance Laboratory in the 1960s.

HNS boasts a higher insensitivity to heat than TNT, and like TNT it is very insensitive to impact.

Hole Liner

A flexible plastic tube which is placed into a blast hole before product is loaded into the tube, providing protection from water or broken ground.

Hole Saver

A plastic funnel which is placed in the collar of a hole, allowing product to be loaded, but preventing fallback of dirt or water ingress.

Hot Ground

Material of a temperature of between 55°C and 100°C.

I

Impact Sensitive

An explosive is considered to be impact sensitive if is can be shown to detonate under exposure to the types of impacts found in normal mining operations.

This would include impact from ground engaging tools (loader and dozer teeth) and drilling operations, crushing between rocks, grinding in a crusher and the like.

It does not include being struck by high velocity (supersonic) projectiles.

Impact Sensitivity

Impact sensitivity testing can be completed using the BAM Fall Hammer apparatus developed by the German Federal Institute for Testing Materials (BAM). Impact energy is imparted to a 40mm3 sample by means of a falling weight. The limiting impact energy is determined as the lowest energy at which a flash, flame, or explosion is observed. The test is used to assess the sensitivity of the test material to drop-weight impact. The BAM Fallhammer test is a part of UN Test Series 3 which is used to assess the ignition sensitivity of suspected explosive materials. As many as 54 trials may be performed and therefore approximately 3 cubic centimeters (cc) of sample may be required.

Impact-Sensitive

Impact sensitive products are known to have detonated under moderate impacts such would commonly occur in a drill and blast operation.

Sources of impact include drilling, machine excavation, rock crushing and the like.

Whilst there are products such as ANFO which are not considered impact sensitive there is always a potential, however small, for abuse of explosives to lead to adverse effects.