Transcript Title: Diavik - WSN Safety Groups

Significant Potential
Incident
Arc Flash
Timmins, Ontario, Canada
March 3, 2011
SERIOUS INCIDENT REVIEW
•
Equipment: Motor Control Center #1 (MCC Bucket)
•
Time/Date: March 3, 2011 @ 13:55
•
Location: Penhorwood Mine Site
•
Conditions: Normal Running Conditions
•
Workgroup: Crushing Operations
•
Supervisor: Gerry Rondeau
•
Manager: Ross Byron
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Scenario description (maximum reasonable
consequence)
An arc flash is an electrical breakdown of the resistance of air resulting in an electric arc
which can occur where there is sufficient voltage in an electrical system and a path to
ground or lower voltage. An arc flash with 1000 amperes or more can cause substantial
damage, fire or injury. The massive energy released in the fault rapidly vaporizes the
metal conductors involved, blasting molten metal and expanding plasma outward with
extreme force. A typical arc flash incident can be inconsequential but could conceivably
easily produce a more severe explosion (see calculation below). The result of the violent
event can cause destruction of equipment involved, fire, and injury not only to the worker
but also to nearby people.
In addition to the explosive blast of such a fault, destruction also arises from the intense
radiant heat produced by the arc. The metal plasma arc produces tremendous amounts of
light energy from far infrared to ultraviolet. Surfaces of nearby people and objects absorb
this energy and are instantly heated to vaporizing temperatures. The effects of this can be
seen on adjacent walls and equipment - they are often ablated and eroded from the
radiant effects.
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Risk Score= Consequence × Likelihood
Incident Risk Score
• Likelihood =
• Consequence =
• Maximum Reasonable Outcome (MRO) =
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Consequence Descriptors
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Likelihood Descriptors
Likelihood
Likelihood description
Frequency
Substance Exposure
Recurring event during the lifetime of an operation /
project
Occurs more than twice per
year
Frequent (daily) exposure at >
10 x OEL
Event that may occur
frequently during the lifetime of an operation /
project
Typically occurs once or twice
per year
Frequent (daily) exposure at >
OEL
POSSIBLE
Event that may occur during
the life-time of an operation
/ project
Typically occurs in 1-10 years
Frequent (daily) exposure at >
50% of OEL
Infrequent exposure at > OEL
UNLIKELY
Event that is unlikely to occur
during the life-time of an
operation / project
Typically occurs in 10-100
years
Frequent (daily) exposure at >
10% of OEL
Infrequent exposure at > 50%
of OEL
RARE
Event that is very unlikely to
occur very during the lifetime of an operation /
project
Greater than 100 year event
Frequent (daily) exposure at <
10% of OEL
Infrequent exposure at > 10%
of OEL
ALMOST
CERTAIN
LIKELY
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What Happened
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Crusher operator enters MCC#1 room to sequence start the crushing plant.
•
Upon starting rod deck, a loud noise is heard.
•
Operator investigates the noise.
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Operator sees that the panel has been blackened.
•
He reports incident to Maintenance Supervisor.
Immediate Response
•
Maintenance Supervisor orders to keep systems down.
•
Investigation begins with Electrician, Crusher Operator and HS Coordinator.
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Snap Chart (timeline of events)
Snap Chart (timeline of events)
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Snap Chart (timeline of events)
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Photos of the incident site and scene
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Photos of the incident site and scene
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Photos of the incident site and scene
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Photos of the incident site and scene
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Process review
(see notes)
1.
Incident / Injury Management:
–
Emergency process followed ? YES
–
Further potential minimized ? YES
–
Employee statements taken ? YES
–
Injury management process followed ? YES
–
Alcohol and Drug Test conducted for all parties associated ? N/A
–
Notifications (Internal & Government agencies etc) carried out accurately in appropriate timeframes ? YES
2.
Scene:
–
Supervisor in attendance? YES
–
Photos taken ? YES
–
Scene and evidence preserved ? YES
3.
Persons Involved:
–
Inductions in place and up to date ? YES
–
Appropriate training up to date ? YES
–
Experience /familiarity with task ? YES
–
Pre-existing injury ? NO
–
Is fatigue / stress a contributing issue ? YES
4.
Procedures, instructions & permits
–
Safe Work Procedure exists for task ? YES
–
Safe Work Procedure is adequate (covers task hazards involved) ? YES
–
Was the procedure for the task followed (as per procedure) ? YES
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Has there been a formal risk assessment for the task? YES
–
Did the risk assessment identify the hazards appropriately ? YES
–
Permits required for task were in place (attach copy) ? YES
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Process review
(see notes)
5.
Contractor Management System:
–
Safety expectations meeting occurred with contractor principals prior to start of contract ? N/A
–
Safety expectations briefing occurred with contract employees at start of contract ? N/A
–
Contractors procedures were reviewed for adequacy prior to commencement ? N/A
–
Accountability for the contractor is clear (defined contract manager) ? N/A
6.
PPE, Tools & Conditions:
–
Was task specific adequate Personal Protective Equipment (PPE) worn ? YES
–
Tools/equipment adequate ? YES
–
Working conditions (light/dark/cold/hot/noise/dust/water/ice/snow) ? NO
–
Was there a change in task or conditions ? YES
7.
Behaviors & risk psychology:
Was the task a “routine task” ? YES
Risk awareness issue (was the person aware of the potential for something undesirable occurring unknown before the event) ?
Risk Judgment issue (was the person aware of the potential for something undesirable to occur, but underestimated the
significance of the event) ?
–
Risk acceptance issue (was the person aware of the consequence potential, but the positive consequences for the action
outweighed the possible negative consequences) ?
–
Were the critical decisions made consciously or subconsciously ? YES
–
Do others people perform the same actions or behaviors ? NO
–
Typically what are the consequences for others who perform the same behaviors ?
–
–
–
8.
Supervision:
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Adequate coverage ? YES
–
Experienced in specific task work ? YES
–
Work Load of supervision ?
–
Had the supervisor visited the task site prior to the incident ? NO
–
Was a clear task assignment given for the task (CPQQRT) NO
–
When last had the supervisor visited the task site prior to the incident ?
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Mitigating Factors (i.e. factors that prevented the outcome from being more serious)
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The bucket door was closed and secured.
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The MCC room is a restricted area.
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Contributing / Causal Factors ( list all factors that are believed to have
contributed to the incident occurring – from SnapChart TM )
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Multi tasking, electrician called away during a critical part of this task.
•
Electrician did not perform a Take 5 to reflect on where he was in his task once he came
back.
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Lessons Learned
•
There is a right time and a wrong time to step away from an unfinished
task.
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The electrician was contacted by production because a piece of
equipment was causing to whole plant to be down and no production
was being made. He chose to leave his task half completed and
started working on the equipment. He then came back to his original
task in the MCC bucket.
•
Upon arrival the plate was noticed to be on, so he continued from
there. Never coming back to ensure the plate was indeed screwed in.
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Root Cause & Corrective Actions (what, who and by when)
Root Cause
Corrective Action
Responsible
Person
Target
Date
Employee distracted at a
critical point in his job
Maintenance Supervisor to
ensure that the Take 5 process
is followed. Employee must be
familiar when a critical
component of a task cannot be
interrupted.
Gerry
Rondeau
March
31,
2011
Electrician did not tighten
the bolts on which secure
the cover.
Maintenance Supervisor to
have a meeting with Electrician
in regards to his actions in this
incident. Meeting to be
documented.
Gerry
Rondeau
March
31,
2011
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