ASCO Power Technologies
50 Hanover Road
Florham Park, NJ 07932
T (800) 937 2726
F (973) 966 2418
www.asco.com
ASCO Services
60 Hanover Road
Florham Park, NJ 07932
T (800) 800 2726
F (973) 966 2433
Date: 6/25/09
Re: 7x24 Fall Conference Submission Outline
Dear Tara
Presentation Outline
Electrical Safety In The Workplace
D. Sandberg
Director Field Service Sales & Operations
ASCO Services Inc.
Overview
The challenge
Requires a careful review of the work required & effect on the facility and mission
Decisions made here have consequences
What planning is required?
How do we sell the necessity of the impact to internal customers?
What electrical & mechanical limitations will we encounter?
The Process
Plan the event
Assess the task
Assess your self
Isolate
Secure
Perform the task
Back out
The problem
Since the invention of electricity, the hazard of Arc-Flash has existed.
Arc-Flash is literally a ball of fire, which is established when there is an electrical fault
A fault is created by an un-intentional connection between current carrying conductors
each other or to ground.
What is an Arc?
Facts
There are two types of faults;
There are two types of faults;
Establish an effective Method of Procedure
Include all stakeholders in development of the
Prepare to secure the system
MOP
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to
PPE is required to operate
Establish boundaries
breakers & disconnects
Establishing Boundaries
Flash
Protection Boundary = The closest approach by any person without PPE.
Approach Boundary = The limit of approach for any unqualified person.
Restricted Approach Boundary = The limit of approach by qualified persons wearing PPE and
having a written MOP. Only as absolutely necessary to perform the required task
Prohibited Approach Boundary = Considered the same as touching an energized part. Prior to
approach, a risk assessment is required.
The challenge
Limited
Knowledge is the Weapon of Choice
In
order to be adequately equipped, we need some information.
We need an arc-flash analysis.
Flash Hazard Analysis
An
arc flash hazard analysis shall be done to protect personnel from injury by arc flash
exposure
Three Options
Flash Hazard Analysis
An
arc flash hazard analysis shall be done to protect personnel from injury by arc flash
exposure
Three Options
Typical Equipment Label
Flash Hazard Analysis
Three
Options
Flash Hazard Analysis
This
analysis determines the flash protection boundary and potential thermal exposure to
personnel working on or near exposure live parts within the boundary. NFPA 70E provides
the calculations required.
This method is complex and requires information not always available.
The next slide explains the issues involved.
Flash Hazard Analysis
The
problem is…we don’t know what we need to know to accurately calculate the arc flash
boundary.
Even if the equipment is stickered changing a component may change the original analysis
calculations
Flash Hazard Analysis
The
Bolted current calculation requires
Flash Hazard Analysis
In
order to calculate the Arc flash protection boundary We would need to know
–The Bolted Fault Current (unlikely – see above
–The bus bar voltage
–The trip speed of the fault protection device controlling our equipment.
We rarely work in buildings where we can get accurate information regarding the breaker trip speed.
Example, if the feed breaker has been tripping in a building, the electrical engineer may place a
longer trip system in to prevent losing power. “
Flash Hazard Analysis
An
arc flash hazard analysis shall be done to protect personnel from injury by arc flash
exposure
Three Options
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Flash Hazard Analysis
Job Safety Analysis
Another alternative is the JSA (Job Safety Analysis)
A document tailored to each piece of standard equipment
The JSA outlines the equipment, task, the hazards and category
of PPE required
Typical Equipment Label
NFPA 70E 130.7
Examples of PPE
Establishing Boundaries
Having
determined the Incident Energy available will enable the calculation of very
specific boundaries.
Establishing Boundaries
Having
determined the Incident Energy available will enable the calculation of very
specific boundaries.
Establishing Boundaries
Typical Equipment Label
NFPA 70E 130.7
Required PPE
Arc Flash Protection
Secure the System (LOTO)
Lock Out / Tag Out (LOTO)
A team sport requiring 100% participation, the winner stays
NFPA 70 E Article 120 spells out the precautions necessary
alive
Secure the System (LOTO)
Electrical
Lock Out / Tag Out
Secure the System (LOTO)
Lock
Out / Tag Out
Lock
Out / Tag Out
Secure the System (LOTO)
Secure the System (LOTO)
Prevent inadvertent operation of the equipment or process in
Establish standard methods for achieving a zero energy state
Comply with applicable standards
order to protect employees
Secure the System (LOTO)
Standards
LOTO Definitions
Energy
apply but are not limited to;
isolating device = a physical apparatus which prevents the transmission or release of
energy such as, but not limited to the following:
–Restraint blocks = manually operated electrical circuits breakers, disconnect switches,
slide gates, and slip blinds or line valves. Where possible, they shall provide visible indication
of the position of the device. Push button, selector switches and other portions of the
control circuit shall not be considered as energy isolating devices.
Lockout / Tagout = The placement of a lock/tag on an energy isolating device in accordance
with an established procedure, indicating that the energy isolating device shall not be operated or
removed until the lock/tag has been cleared.
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Lockout
device = Examples include locks, chains, blank flanges and bolted slip blinds. Lock-out
devices are used to hold an energy-isolating device in a safe position and to prevent the start-up of
machinery or equipment. Whenever possible a lockout device must be used along with a tagout
device. An example of this is when you lockout an electrical disconnect, you must attach the warning
tag to the lock shackle and then attach both the lock and tag to the disconnect. Never remove a
lockout that does not belong to you.
Tagout device = A tag and a nylon tie that is securely fastened to an energy-isolating device to
indicate that the machine cannot be operated until the tagout device is removed. A tag alone will only
serve as a warning device - people can easily remove tags, putting you at risk. Never remove a tagout
that does not belong to you.
Employee Tag = A warning appliance used for the purpose of personnel protection. Its legend
forbids the operation or removal of any energy isolating device and identifies the applier.
Zero Energy State = A state in which every equipment/process energy source has been controlled
either by lockout/tagout or other protective techniques to prevent the unexpected release or
transmission of energy.
Qualified
Individual = An individual who understands how to effectively control the
equipment/process through application of energy isolating devices.
Authorized Individual = A knowledgeable individual processing the responsibility and authority
to perform a specific assignment.
Affected Individual = An affected individual is not qualified to lock/tag out a piece of equipment,
but uses/operates a machine or piece of equipment which lead to maintenance or servicing needs.
Lock
Out / Tag Out
–Verify with drawings
–Secure all sources identified
–Each individual involved must apply their personal lock & tag
–Each individual involved must test the source and verify it is secure
Secure the System
–Complex events involve multiple teams & systems
–Requires a written plan
–Requires a manager
Arc Flash Protection
Back Out & Return System to Service
–Gather all team members and review work done
–Inspect all gear involved
•Are all assemblies, shields etc. installed?
•Are all tools accounted for?
•Are all team members present?
•Do all concur that conditions are safe to re-apply power?
–Each individual must remove their lock & tag from the disconnecting means
–Re-close all disconnecting means
–Test to ensure that all phases are present
–Test each peace of gear worked on
–Sign off plan
Electrical Safety
The
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Conclusion
–Electrical safety is a central concern
–A safety policy is mandatory
–It is our combined responsibility to protect people, facilities & companies
–Many systems do not have concurrent maintainability features
The
Conclusion
–PPE is required to be worn by persons in the vicinity of energized equipment
–Studies similar to breaker coordination to determine the class of hazard at a given
piece of equipment based on the potential energy available
–PPE severely limits the type of work which can be done
–All maintenance routines require equipment to be secured, locked out & tagged out
and possibly removed from the area
Questions?
Contact:
Doug Sandberg
Director Field Service Sales & Operations
ASCO Services Inc.
(973) 966 2079
doug.sandberg@emerson.com
Douglas H. Sandberg
Douglas H. Sandberg
Director, US Field Sales
& Service Operations
ASCO Services
Cc
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