The cause of all accidental detonations:

Friction

Impact

Static

Heat

Fireline is an Oil Field detonating cord from Dyno Nobel. There are a number of different types available with RDX, HMX and HNS coreloads depending on temperature requirements.

Heavy duty insulated wires used to extend an electric blasting circuit to the firing point.

The time period during which a blast may be fired. Planned firing time will be communicated to any person who may be affected by the blast.
The actual firing time is after the clearance is completed (handover from blast controller to shotfirer) and all controls are in place to manage the safe initiation of the shot.

An explosives magazine constructed in accordance with AS 2187.1 in a manner which precludes relocation to another site.

Of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air.

A detonator that will not fire in the presence of a liquid. Used to prevent 'wet firing' of a perforation gun.

Rock that is projected outside the blast clearance zone or outside the site limits must be classed as flyrock.

Factors affecting

Jointed and fissured rocks are more prone to fly rock than strong homogeneous rock. But massive rocks require more charge to achieve good fragmentation and hence cause more problems.

Explosives

Explosives having more Bubble energy throw out more fly rock than the ones where strain energy dominates.

Blast Design

Blasting parameters like burden, spacing, charge per hole, stemming, and delay interval play an important role in the throw of the blast. Burden should be selected to take into account the crater effect where in rocks get thrown out from cavities or weak zones in the bench. There should also be adequate delay between rows of holes to allow room for the rock to swell and displace previously blasted material.

The primary sources of flyrock are face bursting, rifling and cratering.

Foreign Bodies (Also known as Tramp Material) not intended to be present in a process (such as bolts, nuts, gravel, etc), that can have an adverse effect on the process and may cause an undesired event or deviation from the design intent.

A formal risk assessment will contain, as a minimum, the following components:

• Step by step description of all the activities undertaken in the task
• A list of the identified hazards or risks associated with each of the steps.
• A description of the consequence of an adverse outcome.
• An estimate of the liklihood or frequency, from never to always.
• An estimated rating of the risk consequence, from insignificant to catastrophic.
• An overall risk rating, Low, Moderate, High, Extreme, generally guided by a risk cube.
• Existing and Addiitonal controls to manage the identified risks.
• Signoff by the risk team

Example of completed Formal Risk Assessment.

Example of Risk Cube to rate risk.

The Fortan™ Advantage Bulk System heavy ANFO blends is specifically designed for difficult blasting applications found in open cut hard rock mining.

Fortan™ Advantage is designed to increase explosive energy in dry blastholes, however the higher density emulsion blend of Fortan™ Advantage 50 can be used in dewatered blast holes.

The AN content enables high heave to be achieved. It is not suitable for ground containing reactive sulphide.

The size distribution of material left in the muck pile after the blast.
An increase in fragmentation corresponds to a higher percentage of rock fragments passing through a particular aperture size.

A face or void aligned at the end of the rows of the blast.
The free end provides holes on the end of the rows with relief in two directions, to the face and to the end.

Friction sensitivity testing can be completed using the BAM Friction apparatus developed by the German Federal Institute for Testing and Materials (BAM). The test is used to measure the sensitivity of test materials to frictional stimuli. The test is a part of UN Test Series 3 which is sued to assess the ignition sensitivity of suspected explosive materials. A 10mm3 sample is spread on a porcelain plate and the plate is then dragged under a weighted porcelain peg. The force on the peg is varied and the limiting friction load is determined as the lowest force for which a flash, flame, or explosion is observed. As many as 60 trials may be performed, and therefore approximately 1 cubic centimeter (cc) of sample may be required.

Fume is the general term for toxic gases produced by blasting.

NOx Fume produced from a surface blast.

The common fumes are carbon monoxide (CO) and oxides of nitrogen (NOx)

The group of gases known as Oxides of Nitrogen or NOx, of which the most common are nitric oxide (NO) and nitrogen dioxide (NO2), are often found as by-products in the post-blast gases of ammonium nitrate-based explosives. Together, these gases are loosely referred to as "NOx". Nitric oxide is invisible, but nitrogen dioxide ranges from yellow to dark red depending on the concentration and size of the gas cloud. These gases are toxic.

There are a number of causes for fume generation. These include:

• Explosives delivered into the blasthole with poor Oxygen Balance
• Lack of confinement in soft ground
• Loading into wet ground
• Dynamic desensitisation

The attached file provides detailed information on fume generation and management.

The combination of bridge wire and pyrotechnic substances which when subjected to electric current provides ignition to the detonator.