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.