Blast swath

Blast fumes are reaction products after the ignition of nitrate explosives and related chemical and physical reaction ( detonation ).

The poisonous plume that forms when nitrate explosives are detonated is also known as a bojan. It is a mixture of mine weather , water and dust with the reaction products of the explosive charges ( e.g. nitrous gases ).

Nitrogen oxides

Very high concentrations of nitrous gases can be found in explosive clouds. These lead to symptoms of poisoning and, in high concentrations, to death if inhaled. Examples of nitrous gases are nitrogen monoxide (NO) and nitrogen dioxide (NO ₂ ).

Very high concentrations of nitrous gases (nitrogen oxides) are created when highly explosive explosives react at subsonic speed (thus not detonating . This usually creates flames or even glowing tiny particles in connection with the nitrous gases (so-called deflagration )).

causes

Causes of explosive clouds are

unavoidable chemical sequelae when using explosives,
Incomplete detonation of the explosive (e.g. due to overcharging, insufficient initiation or due to explosives that have become damp),
Insufficient or missing containment (so-called stocking) of the explosives.

Protective measure

By ventilation with fresh air via a Lutte the blast fumes are in the pressing and / or sucking process mining diluted and removed. In addition, the pile is hosed down with water, as part of the steam can remain in the pile.

In order to protect the people involved in the blasting from explosive swaths, the planned ignition point should be in the incoming weather stream and not in the main downwash stream. If this cannot be avoided, breathing apparatus ( e.g. filter self-rescuers ) must be available.

literature

Dynamit Nobel Vienna (DNW) and Schaffler & Co. GesmbH. (Ed): Advice on blasting technology . 11th edition. Self-published , St. Lambrecht 1989.

Web links

Precipitation of nitrous gases from explosive clouds by spraying (accessed on April 27, 2020)
Blasting work (accessed April 27, 2020)
Technical rule on explosives law Blasting work (SprengTR 310 - Blasting work) (accessed on April 27, 2020)
Blast swaths during tunneling (accessed April 27, 2020)
Explosives and their influence on ground and surface water (accessed April 27, 2020)

Individual evidence

↑ The trimmings can for example consist of Latvians , sand , the finest stones , water or calcium chloride (to bind dust). In the mining industry, there is also the saying: “Well dammed up, halfway through.” Rule of thumb: the less explosive an explosive is, the more material is required.

[1] The trimmings can for example consist of Latvians , sand , the finest stones , water or calcium chloride (to bind dust). In the mining industry, there is also the saying: “Well dammed up, halfway through.” Rule of thumb: the less explosive an explosive is, the more material is required.