CSCS Shot Firing flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Risk assessment hierarchy

A statutory approach that requires hazards to be eliminated first, then risks reduced, then residual risks controlled, with the process documented before shot firing begins.

Notifiable incident

An event such as a misfire, theft, loss of explosives, injury or uncontrolled explosion that must be reported to the regulator, often police too, within a set deadline.

Competence

The combination of training, qualification and relevant experience that authorises a person to carry out a specific shot firing task safely and lawfully.

Blast plan

A site-specific, signed-off document setting out hole layout, explosive types and quantities, timing, stemming and exclusion zone, forming the operational expression of legal duties.

ANFO

A blasting agent made from ammonium nitrate prills and fuel oil; inexpensive and low in water resistance, needing a strong primer and confinement to detonate reliably.

Velocity of detonation

The speed at which the detonation shock front travels through an explosive column, a key property determining energy delivery, fragmentation and suitability for the rock.

Emulsion explosive

A water-resistant explosive with adjustable density and energy, produced by sensitising an oxidiser-fuel emulsion, suitable for wet holes and varied ground conditions.

Magazine segregation

The practice of storing detonators separately from bulk explosives and detonating cord, with stock reconciliation and protection from impact, heat, moisture and unauthorised access.

Electronic detonator

A programmable detonator tested individually through a logger or blasting machine, giving very tight timing accuracy and recording continuity and fault codes.

Shock tube system

A non-electric initiation system immune to stray currents and radio frequency, but requiring protection from kinking, cutting, abrasion and hot work.

Circuit continuity test

A pre-firing check of an electric detonator circuit confirming resistance and continuity, carried out with the area isolated and personnel clear of the charge.

Detonating cord rating

The explosive content of detonating cord expressed in grains per foot or grams per metre, indicating its capacity to initiate downlines and trunklines.

Powder factor

The mass of explosive used per unit volume of rock broken, a core design parameter used to compare blast designs and reconcile results with the plan.

Burden

The distance from a charged hole to the nearest free face; too large a burden overconfines the charge, risking misfires and flyrock.

Stemming

Inert, angular, non-combustible material placed above the explosive column, generally at least the burden in length, to confine gases and reduce flyrock and airblast.

Spacing to burden ratio

The relationship between hole spacing and burden in a blast pattern, commonly around 1.0 to 1.5 for bench blasting, adjusted for fragmentation and wall control.

Subdrill

The length a blast hole is drilled below the intended floor level, ensuring the full bench is broken to grade without leaving a hard toe.

Pre-split blasting

A technique using closely spaced, lightly charged holes fired before the main blast to create a fracture plane that protects the final wall from damage.

Exclusion zone

The cleared radius around a blast, sized from the design and site conditions to protect against flyrock, fumes and airblast, confirmed clear before firing.

All-clear signal

The audible signal given by the shot firer after inspection confirms no misfires or undetonated explosives remain, permitting re-entry to the blast area.

Misfire

A condition where the full round has not detonated after the expected delay; the area is treated as live and re-entry is delayed per procedure.

Misfire procedure

The sequence of isolating the firing circuit, maintaining the exclusion zone, waiting the prescribed time, then investigating and re-blasting or recovering under supervision.

Post-blast inspection

The shot firer's examination of the muckpile for undetonated explosives, cut-offs and misfires before the all-clear is given and work resumes.

Blast fume hazard

Carbon monoxide and oxides of nitrogen produced by detonation, which can persist in confined or low-wind conditions and require ventilation and delay before re-entry.

Peak particle velocity

The measured ground vibration amplitude at a receptor, used with site-specific limits to assess whether a blast is acceptable to nearby structures.

Scaled distance

Distance divided by the square root of the maximum charge per delay, used to compare blasts against site-specific vibration and airblast criteria.

Airblast overpressure

The airborne pressure wave from a blast, reduced by good stemming, avoiding exposed detonating cord and firing in favourable wind and weather conditions.

Flyrock control

Management of rock throw by ensuring adequate burden and stemming, correct delay sequencing, no overcharging and clearing the zone to the design radius.

Blast record

A document capturing date, location, shot firer, design, hole data, explosive and detonator quantities, delays and results, retained for the statutory period.

Explosives reconciliation

The chain-of-custody accounting of explosives from receipt through issue to use or return, checked against stock to detect loss or discrepancy.

Pre-blast briefing

Communication with site personnel, neighbours and authorities covering the blast time, warning signals, exclusion zone and emergency arrangements before firing.

Shift handover record

A documented transfer of information between shot firers or shifts, including live rounds, misfires and magazine status, to maintain continuity of safety controls.