Transcript Blasting safety

WELCOME
YOU ALL
SAFETY DURING
BLASTING OPERATION
GUIDELINES FOR BLASTING
AND SAFE USE OF EXPLOSIVES
Among all of the professions on
earth, there is none that
demands a stricter commitment
to safety, proper training,
product education, and respect
for the rights of others than
that of the Blasting Engineer and
Explosive engineer.
THE GUIDE LINES MAY DIVIDE INTO FOUR
GROUPS:
- BEFORE DRILLING
- DURING DRILLING AND
CHARGING
- DURING BLASTING
- AFTER BLASTING
THE DRILLING AND BLASTING WORK
PROCESS
BASIC DESIGN PRINCIPLES
 MINIMUM TWO FREE FACES SHOLD BE AVAILABLE
FOR BLASTING.
 THE FRONT ROW CHARGE SHOULD BE ADEQUATELY
DESIGNED TO MOVE THE FRONT ROW BURDEN.
 BACK ROW HOLES SHOULD BE DRILLED AT AN
OPTIMUM DISTANCE FROM THE FINAL DIGLINE TO
PERMIT FREE DIGGING AND YET MINIMISE DAMAGE
TO THE WALL.
 THE MAIN CHARGE AND BLAST HOLE PATTERNS
SHOULD BE OPTIMIZED TO GIVE THE BESTPOSSIBLE FRAGMENTATION AND DIGGING
CONDITIONS FOR MINIMIM ‘PF’.
 ADEQUATE DELAY SHOULD BE USED TO ENSURE
GOOD MOVEMENT TOWARDS FREE FACES AND
CREATION OF NEW FREE FACES FOR FOLLOWING
ROWS.
DURING DESIGN THE FOLLOWING POINTS
SHOULD KEEP IN MIND:
 IS IT A CONTROLLED BLASTING
 ARE THERE ANY CRITICAL STRUCTURES TO
TAKE CARE
 ARE THERE ANY HISTORICAL STRUCTURES
 PERMISSIBLE LIMITS FOR THOSE CRITICAL
STRUCTURES
 THE MAXIMUM CHARGE MAY EXPLODE TO
RESTRICT THE DAMAGE TO STRUCTURES AND
. ADJACENT ROCK MASS.
 THE MAXIMUM SIZE OF FRAGMENTATION
CONTROLLED BLASTING TECHNIQUE
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Used to reduce overbreak and minimise
the fracturing of the rock of the
boundary of an excavation
Basic controlled blasting techniques are
1) Line Drilling
Dia of hole - 50 to 75mm
 Spacing – 2 to 4 dia
 No explosives
 Depth upto 9.0m

CONTROLLED BLASTING TECHNIQUE
2)Presplitting
Dia of hole - 50 to 100mm
 Spacing – 6 to 12 dia
 Explosives- spring loaded on detonating chord
 Depth upto 15.0m

3)Cushion blast
Dia of hole - 50 to 150mm
 Depth upto 30.0m

4)Smooth blast
DRILLING
-THE DESIGN SHOULD BE EXPALINED CLEARLY TO DRILLING
TEAM.
- THE DESIGN SHOULD BE MARKED BEFORE DRILLING
STARTS. NO OF HOLES AND DIRECTION OF HOLES IN EACH
ROUND.
- PROPER CARE SHOULD BE TAKEN TO MAINTAIN THE DRILL
HOLE ANGLE.
- THE DEPTH OF EACH HOLE SHOULD MAINTAIN AS PER
DESIGN.
- THE NO OF HOLES SHOULD BE CHECKED AFTER DRILLING.
DURING CHARGING
TRANSPORT OF EXPLOSIVES:
 TRANSPORT OF EXPLOSIVES FROM THE MAGAZINE TO
TEMPORARY STORAGE SHALL BE DONE IN DAYLIGHT .
 THE MECHANICAL VEHICLE USED FOR TRANSPORT SHOULD BE
APPROVED MY ‘DGMS’.
 EVERY VEHICLE USED FOR EXPLOSIVE SHALL BE MARKED
WITH WORDS ‘ EXPLOSIVE’ IN RED LETTERS ATLEAST 15 cm
HIGH ON WHITE BACKGROUND.
 EXPLOSIVES AND DETONATORS SHALL BE TRANSPORTED IN
SEPARATE VEHICLES / TRIPS
VAN CONSTRUCTION
DIESEL
MAIN MAGAZINE
 ATLEAST TWO FIREEXTINGUISHERS SHALL BE THERE IN
VEHICLE USED FOR TRANSPORT OF EXPLOSIVE.
 IN SHAFTS, EXPLOSIVES SHALL NOT BE CONVEYED DURING
THE MAN WINDING HOURS, AND NOT MORE THAN MAN
WINDING SPEEDS.
 THE WINDING ENGINE DRIVER, BANKSMAN SHALL BE
INFORMED BEFOREHAND.
 THE QUANTITY OF EXLPOSIVE AND NO OF DETONATORS
SHOULD BE CHECKED BEFORE CARRYING TO UNDER GROUND/
SHAFT
THE CHARGE AND THE DETONATOR NUMBER TO PUT INTO
EACH HOLE SHOULD BE CHECKED.
THE DETONATOR SHOULD BE CHECKED FOR BREAKAGE OF
LEADS AND ANY DEFECT.
IN EACH HOLE STEMMING SHOULD BE DONE AS PER
DESIGN AND THE MATERIAL SHOULD BE PRESCRIBED ONLY.
AFTER CHARGING IN ALL THE HOLES, THE CONNCTIONS
SHOULD BE MADE BY SHOT FIRER WITH HELP OF BLASTING
INCHARGE.
ALL THE CONNECTIONS SHOULG BE CHECKED ONCE AGAIN
BY SHOTFIRER AND BLASTING INCHARGE BEFRE
CONNECTING TO MAIN CABLE.
Loading Explosives:

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No operating equipment within 50 feet of
loaded holes
Load only those holes intended to be fired
in the next round
Warning signs posted
Check all holes for
depth prior to loading
APPARATUS
ALL THE BLASTING APPARATUS AND THE APPARATUS USE NEAR
.
BY SHOULD
BE EITHER INTRINSICALLY SAFE OR FLAMEPROOF
AND APPROVED BY DGMS
INTRINSICALY SAFE OPERATUS ARE LOW POWER EQUIPMENTS
LIKE
-BELLS
-RELAYS
-TELEPHONES
-SIGNALLING
-REMOTE CONTROL
-EXPLODERS
AFTER BLASTING
 THERE IS CHANCE OF ‘MISFIRES’ AND ‘BLOWN OUTSHOTS’.
SO, MEN SHOULD NOT BE ALLOWED TO RETURN TO THE
PLACE UNLESS THERE IS CLEARENCE SIGNAL FROM THE
SHOTFIRER OR BLASTING INCHARGE.
 MINIMUM TIME GAP OF 5 min FOR ELECTRIC BLASTING
AND 30 min FOR NON-ELECTRIC BLASTING SHOULD BE GIVEN
BEFORE ENTERING THE BLASTING ZONE.
 EXPLOSIVES THEORETICALLY CONTAIN SUFFICIENT
OXYGEN TO COMPLETE COMBUSTION, BUT COMBUSTION IS
SELDOM PERFECT AND ‘CO’ IS LIABLE TO PRESENT IN THE
BLASTING FUMES.
IN ADDITION POST DETONATION FUMES CONTAIN NITOROUS
FUMES.
SO, MEN SHOULD NOT BE ALLOWED TO RETURN TO THE PLACE
UNTIL THE FUMES HAVE BEEN CLEARED BY THE VENTILATION.
AFTER THE STIPULATED TIME GAP THE SHOT FIRER/BLASTING
INCHARGE SHOULD CHECK FOR ANY MISFIRES OR BLOWN OUT
SHOTS.
IF BLAST IS ALL RIGHT THE FINAL SIREN MAY GIVEN FOR
CLEARANCE .
MISFIRES
MISFIRE- IS ONE WHICH THE DETONATOR FAILS TO EXPLODE OR
HAVING EXPLODED, FAILS TO IGNITE THE CHARGE.
REASONS DEFECTIVE SHOTFIRING EXPLODER BY WHICH REQUIRED
VOLTAGE IS NOT GENERATED.
 BAD CONNECTION BETWEEN EXPLODER AND SHOTFIRING
CABLE, BETWEEN CABLES AND DETONATOR LEADS.
 DEFECTIVE SHOT FIRING CABLE, BROKEN WIRES INTERRUPTING
THE CIRCUIT OR DAMAGED INSULATION CAUSING A SHOT
CIRCUIT.
 BROKEN DETONATOR LEADS
 BAD EXPLOSIVE (EITHER DUE TO BAD MANUFACTURE OR DUE TO
DETERIORATION DURING STORAGE).
DEALING WITH MIS-FIRES
DISCONNECT THE CABLE AND WAIT FOR PRESCRIBED PERIOD.
 CHECK MAIN CABLE AND DETONATOR IF ALL THE SHOTS ARE
FAILED
 CHECK SUB CONNECTIONS, AND PARTICULAR DETONATOR LEADS,
IF SOME HOLES ARE FIALED.
 RECONNECT,IF ANY DEFECT CONNECTIONS FOUND AND CONNECT
THE CABLE AND FIRE ONCE AGAIN.
 IF AGAIN FIALED, FENCE THE ENTRANCES TO THE PLACE.
 DRILL A FRESH HOLE ATLEAST 30 cm AWAY FROM THE MISFIRED
HOLE AND AS FAR AS POSSIBLE PARALLEL TO MISFIRED HOLE.
 CHARGE THE NEW HOLE WITH PROPER STEMMING IN THE USUAL
MANNER.
 FIRE THE NEW HOLE IN THE USUAL MANNER.
 SEARCH FOR THE UNFIRED DETONATOR AND CHARGE. IF THEY
ARE NOT FOUND LAOD THE MATERIAL BY MANUAL IN A SEPARATE
BUCKET DISTINCTLY MARKED AND SEND IT TO THE SURFEACE FOR
FURTHER SEARCH.
• DESTROY THE MISFIRED EXPLOSIVE (CHARGE) AND
DETONATOR ON THE SURFACE, IF TRACED OUT.
• IF NOT FOUND, REPORT THE CIRCUMSTANCES FULLY TO THE
SHOT FIRER OF THE NEXT SHIFT.
ENVIRONMENT
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The detonation of three different ammonium nitratefuel oil (ANFO) mixture illustrates the principle of
oxygen balance.
1) 94.5% AN-5.5% FO( Oxygen balanced)

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2) 92% AN-8.0% FO( Fuel excess)

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3NH4NO3 + CH2 = 7H2O+CO2+3N2+ 930Kcal/Kg
2NH4NO3 + CH2 = 5H2O+CO+2N2+ 810Kcal/Kg
3) 96.6% AN-3.4% FO( Fuel shortage)

5NH4NO3 + CH2 = 11H2O+CO2+4N2+2NO+ 600Kcal/Kg
FIRST AID
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HIT INJURY BY PROJECTILES

INHALATION OF EXPLOSIVES

INHALATION OF BLASTING FUMES
WARNING
NOT TO USE
 MOBILE / CELL PHONE
 HAND SETS &
 WELDING
Emergency Response
 Fire
 Thunder storm
 Explosive van accident
 Any
materials
un-attended
explosive
Any Questions please
Thank U