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Blasting & Flyrock AwarenessRecognizing the Hazards
Prevent injury to people
Prevent damage to property
Legal Standards
OSHA29 CFR Part 1910 - General Industry29 CFR Part 1926 - Construction
MSHA56.6000 - Metal & Non-Metal Mines
Bureau of Alcohol, Tobacco and Firearms
DOT
Basic Blasting Terminology
Blaster-in-Charge Blasting Plan Blast Area Flyrock Early-Warning
Signal Final-Warning
Signal All-Clear Signal
Rock blasting is the controlled use of
explosives to excavate or
remove rock.
It is a technique used most often
in mining and civil engineering.
Best Practices:
• ensuring that all personnel have evacuated the blast area during shot firing;
• using adequate blasting shelters for employees whose presence is required in the blast area
• controlling and monitoring all entrances to the blast area; ensuring that the blast is properly designed,drilled, and loaded; and
• emphasizing education and training to enhance skill levels for implementation of engineering control techniques.
Conduct Pre-Blast Meeting• Review of weather conditions
• Communicate number of holes
• Calculate bags per hole
• Discuss reasons to turn off electronic
devices
• Review personnel location
• Discuss stemming process
• Discuss gas and fume releases
• Remind those working alone to stay
in communication w/supervisor
An example of a firing pattern which provides separate delay time for the blastholes and gives good fragmentation
as well as good breakage.
Early-Warning Signal
___ minutes before shot is fired.
Warns holes have been loaded with
explosives and prepared.
Means blast area is clear, guards have
stopped traffic into area.
Blast crew inspects grounds to make sure
no people or equipmen is in the blast area.
Every sites warning signals are unique!!
Final-Warning Signal
___ minutes before
firing.
Timing is different on
each site.
Radio silence is
necessary.
Guards will halt blast if
they sight anyone in
area.
All-Clear Signal
Blaster can't order the all-clear signal just
yet.
The blaster must inspect the area to see if
there are any misfires.
It may take minutes, hours or days to
determine if there is a misfire.
Stay out until the All-Clear signal sounds.
Warning Signals
Be alert and share information
Know the blasting time, blast area and clearing procedure; and
Do not enter the blast area until an “all-clear” signal is sounded.
The location of the blast within the permit area allows the regulator to verify the distance.
Know the location of the blast
Check the distance!!
North
Jones
Residence
690 Feet
Permit Area
Rock blasting in northern Ontario to make way for new highway upgrades.
The six exposures were taken over a span of 3 seconds.
This animation is displayed over 6 seconds.
Excavation crews working on sites involving blasting operations may be exposed to the hazards of undetonated charges during removal of blasted rock.
Flyrock is caused by a mismatch of the distribution of the explosive energy, geomechanical strength
of rock mass, and confinement.
A B C D E
Optimum Depth
A professional baseball pitch averages 90 mph, or slightly faster.Flyrock has been clocked at 400 mph. Can you dodge that?
Protect Yourself!
July 2002 - West Virginia
A truck driver and his supervisor were watching a blast from 1/2 mile away - waiting for the "all clear" signal.
A rock slammed into the front windshield and exited the rear. It somehow missed both people. No one was hurt.
MSHA Part 48
State of Alaska: 11 AAC 95.335. Blasting Standards
(a) A person may not discharge an explosive in the following areas without first obtaining a variation under 11 AAC 95.235:
(1) Type A or Type B stream riparian areas in Region I; and
(2) within all riparian areas in Region II or III.
(b) During blasting, an operator shall minimize the amount of flyrock materials deposited into fish-bearing waters.
Authority:AS 41.17.010 AS 41.17.080
Explosives Security ReminderInspect, verify each magazine is properly secured
according to all applicable regulations, company
policy, as well as manufacturers recommendations
Explosives Security Reminder
Ensure that any vehicle used to transport explosives is properly secured and attended.
Explosives Security Reminder
Verify that inventories of explosives are correct
Copy is maintained in magazine with duplicate at mine office
Explosives Security Reminder
Verify person’s identify before allowing them to enter explosive magazines or review inventory records
Misfires found during the post-blast inspection
Exclude all employees from danger zone.
No other work except that required to clear the misfire.
Only the Blaster-in-Charge handles all the sequence of events following a misfire.
Extra care must be taken, as the designed pattern
HAS changed.
Review facility’s security measuresAre further measures necessary to protect explosives from theft?
Explosives Security Reminder
Explosives Security Reminder
Immediately report shortages, loss or theft of any explosive material to:
1-888-ATF-BOMB
Conclusion:
Good communication between the
driller, blaster, access control guard,
and miners is the key to a safe blasting
operation.Thank you for your participation.