Ground broken beyond the design line of blast holes most recently detonated.

Overbreak on the right wall of a large underground excavation.

Backfill sheets are provided to charging operations to enable over length holes to be brough back into tolerance with the design charge depth.

A complete backfill sheet contains the following information:

Ballistic Discs provide a safe and effective way of remotely clearing hang ups and upstanding rill in draw points and stopes. When detonated a ballistic disc produces a large steel slug that is propelled at hypersonic velocity (2000-2600 m/s). The kinetic energy transferred on impact, up to 60 MegaJoules with the BD514, shatters the target area. As accurate aiming is paramount, provision for
a laser aiming attachment is fitted to all disc faces.
Ballistic Disc use in underground mining enables a true "non-stope entry" method of safely removing hang ups. Accordingly Ballistic Disc use is mandatory in several Australian underground mines. Ballistic Discs further aid safe underground operations as they permit the abortion of firing at any stage, and safe recovery of an aborted or misfired round.

Insulated wires (usually of a lighter gauge than the firing cables) used between the detonator lead wires and the firing cables or for lengthening the lead wire of an electric detonator.

A bi-directional booster is crimped onto detonating cord to increase the donor output of the cord.

The booster contains about 2 grams of either HMX or HNS explosives.

The area around a blast that must be evacuated of personnel and equipment during the firing of a blast.

The clearance zone is identified on the firing plan which will also show blast guard positions and other information relevant to the firing.

A person who may be appointed to handle the logistics of the clearance of the Blast Exclusion Zone including (but not limited to) the following:-

• Removal / relocation and preparation of equipment currently within the Blast Exclusion Zone;
• Confirming the position and location of the Blast guards;
• Completing the clearance sweeps of the Blast Exclusion.

Zone once the guards are in place and the area secured.

A blast guard is a person responsible for ensuring the blast clearance zone is evacuated prior to the firing of a blast.

The attached document provides detailed information on the practice of blast guarding.

A mat made of rope, rubber strips, polyethylene tube or similar material, placed over the area or materials being blasted to prevent the scattering of blast-generated debris.

A blast plan, should include, but not be limited to, the following:

• Location of the proposed blasting.
• Description of the proposed blasting.
• Permits / licences required for the project.
• Identification and position of the person responsible for the project including project safety and security.
• Identification and position of person who has given approval to use explosives on the project.
• Key appointments and responsibilities.
• Shotfirer’s details.
• Details of the risk management assessment.
• Details of adjacent structures or services that influence the blast design.
• Details of reports, drawings and records consulted.
• Layout plan of the blast including drilling pattern and hole depths.
• Detonation sequence / effective charge mass per delay (MIC) / powder factor.
• Type of explosive to be used and quantity required.
• Method of initiation.
• Type of firing equipment and procedures.
• Drilling procedures.
• Explosive loading and charging procedures.
• Explosive storage and handling procedures.
• Security procedures for the site and the blast, including explosives.
• Environmental considerations for airblast overpressure, ground vibration.
• Details of communication systems.
• Warning procedures.
• Traffic management plan.
• Proposed dates and times of blasting.
• Details of the exclusion zone.
• Method of notification to owners and occupiers of structures, and providers of services adjacent to the blast.
• Influence of weather.
• Loading in poor light conditions or reduced visibility.
• Cessation of explosive-related activities during electrical storms.
• Misfire management system.
• Post blast assessment and inspection procedures.
• Provision for post-blast comments.
• Signature spaces for the plan author, shotfirer and person who approves the plan.

Blast records are to be kept by the shotfirer of all blasts loaded and fired.

The various state regulations require a record of all blasts and the type and quantity of explosives used.

The blast clearance zone must also be defined and documented for surface blasts.

Australian Standard AS2187.2 Use of Explosives Appendix A provides the following guidance:

A3 BLAST RECORDS
Details of the blast should be taken and maintained, including but not limited to the following:
(a) Environmental conditions at the time of the blast.
(b) Monitoring equipment including type, serial number and location.
(c) Details of measurements recorded during the blast.
(d) Details of flyrock or fly.
(e) Details of incidents and complaints.
(f) Comment on the results of the blast.
(g) Proposed modification to the blast plan for future shots.

The blast report is the record of blast firing.

Details of the blast should be taken and maintained, including but not limited to the following:

• Drill pattern, product loaded (type and quantity) initiation sequence.
• Environmental conditions at the time of the blast.
• Monitoring equipment including type, serial number and location.
• Details of measurements recorded during the blast.
• Details of flyrock or fly.
• Details of incidents and complaints.
• Comment on the results of the blast.
• Proposed modification to the blast plan for future shots.

An area including all holes to be loaded plus such as required for safe loading operations.

Certain high explosives, such as those consisting primarily of ammonium nitrate, in which none
of the ingredients are classified as an explosive and which normally require a booster for initiation.

A Blasting Ohm Meter is a test device for checking circuits containing electric detonators.

A blasting ohm meter has an output limited to below the no fire current of standard electric detonators.

BlastPED has been developed as a safer alternative to traditional safety fuse and cable based firing systems. This radio based remote blasting system allows personnel to be away from the blast area, reduces the number of misfires, and eliminates the need for expensive blasting cabling networks.

• The BlastPED System operates off the existing PED Transmission System and only requires a software upgrade to operate.
• BlastPED has been developed to eliminate the high cost of maintaining the integrity of underground blasting cables. By eliminating these cables, costs are reduced on maintenance and lost production due to misfires.
• While the BlastPED system is extremely secure, it is also simple to operate for the authorised personnel. The software is similar to the PED operating software, PEDCALL; therefore personnel do not need to learn a new system.
• The actual BlastPED receiver itself is easy to connect and operate. The user connects the firing cable, ensures the BlastPED has synchronised, and then turns the key. It is then up to the PEDCALL operator to enter the ARM & BLAST command from security disk and transmit the messages, once the area has been cleared of personnel and permission has been received to fire.
• For safety reasons, two seconds after firing the BlastPED automatically locks out. The unit will remain locked until it is manually reset by turning the safety key to the “SAFE” position.

BLASTPLAN-PRO is a graphically based initiation design and simulation package for Shotfirers and Drill and Blast Engineers.

A free, fully functional system is available for download at www.blastplan.com.au

A blended explosive generally refers to a mixture of ammonium nitrate and emulsion. A range of blends are available from straight ANFO through a 50/50mix to straight Emulsion.

Blends containing more ANFO than Emulsion are known as Heavy ANFO's or HANFO

Blends containing more Emulsion than ANFO are known as Doped Emulsion

Blends containing more than 40% Emulsion have good water resistance and where Emulsion content is over 50% the product is considered suitable for loading into fully wet holes.

Blends containing more than 50% Emulsion generally need to be chemically gassed for sensitivity.

A block slide is a translational slide in which the moving mass consists of a single unit or a few closely related units that move downslope as a relatively coherent mass.

Resembling a block in shape.

A cap-sensitive explosive with a high VOD used generally in small quantities to rapidly attain and maintain a high rate of detonation through the main charge.
Generally refers to a cast booster containing Pentolite.

Electric detonator for firing from the bottom of a perforating gun.

May be fluid sensitive of fluid resistive

A pattern of holes adopted for blasting to a new level below an existing floor or below existing surface mining.

The ability of an explosive to break or shatter rock by shock or impact as distinct from gas pressure.
The shattering effect of the energy released in an explosion.

The explosive strength value of a unit volume of an explosive material expressed against a standard reference such as ANFO.

A blast hole which has been enlarged (chambered) to accommodate extra explosive over a portion of its length (usually at the bottom) by exploding a small charge.

The burden is the distance between a blasthole which is to be fired and the nearest void or free space.

Note that two burdens are defined, the drilled burden as shown in the diagram and the dynamic burden which is the true burden at the instant the hole fires.

The dynamic burden is influenced by both the drilled burden and the delay timing.

The burn, or parallel hole, cut relies on larger diameter uncharged holes to provide the initial void to fire into.

These ‘reamer’ holes have limited volume so the burn cut starts with firing holes on very small burdens to ‘nibble’ the rock out until sufficient void and a second free face is created.

The initial holes pulverise the small amount of rock in the cut and then use the high pressure gases to clear the void. Unlike bench or stripping blasting the broken rock must undergo a change of direction and be squirted out the narrow cut area. This process takes some time and is the reason for the use of ‘Long Period’ (LP) delays.

As a second free face and void is developed blasting transitions to stripping geometries with maximum burdens and sufficient relief.

The burn cut requires a high degree of drilling accuracy to be reliable and there is a trend toward machine guidance systems on drilling machines to optimise drill accuracy.

Whilst these have been shown to be very effective in maximising blast effectiveness, and have been widely adopted into construction tunnelling, they have had limited acceptance in mine development due to operator resistance and maintenance issues.

The distance that the initiation system has functioned in front of the blast firing.

Any portion of a drill hole or blast hole left after blasting.
NOTE: It could contain some unexploded material.