Embed Size (px)
Citation preview
©2008
4-1
Methods of Control
Module 4
©2008
4-2
Recognize
Control
Evaluate
©2008
4-3
Identify the three types of control that should be used to achieve electrical safety.
Module Objectives
Identify the engineering, administrative and PPE controls you use on your job.
Identify facts and procedures relating to lockout/tagout.
©2008
4-4
Module Objectives
Recognize when a work permit is required to work on energized electrical circuits.
List the steps required to achieve an electrically safe condition.
Recognize the appropriate warning signs to alert employees to the danger of electricity.
©2008
4-5
Recognize the appropriate PPE to use based on the calculated energy value of an energy source.
Module Objectives
Given a case study, determine the most appropriate method of control and necessary corrective action.
©2008
4-6
A control is a measure or an action that is taken to eliminate current hazards and to prevent
future hazards.
What is a Control?
©2008
4-7
Engineering
Three Types of Control
PPE
Administrative
©2008
4-8
Controls that are engineered into the job. The focus is on
eliminating the hazard altogether.
Engineering Controls
©2008
4-9
Redesign of equipment
Substitution of material, equipment or process
Change process to eliminate exposure
Use of barriers to isolate the hazard
Use of barriers or shields to isolate the worker
Engineering Control Examples
©2008
4-10
Safe WiringChoose the correct size of wire for the amount of current in the circuit.Make certain that the wire’s insulation is appropriate for the voltage.Make sure the wire is tough enough for the conditions.Make sure the connection is reliable.Make sure the connections are protected.
©2008
4-11
Wire Sizes
©2008
4-12
Controls that reduce employee exposures
through administrative methods. Depend on
constant implementation or intervention.
Administrative Controls
©2008
4-13
Education and training
Procedures to limit exposure
Maintenance
Good housekeeping
Signs and warnings
Distance
Administrative Control Examples
©2008
4-14
Controls that are worn by employees to
protect them from the environment.
Personal Protective Equipment (PPE)
©2008
4-15
Protective Clothing
Protective Gear
PPE Examples
Photo courtesy of Schneider Electric
©2008
4-16
Uncontrolled Arc Blast
©2008
4-17
Arc Blast Controls
EngineeringAdministrativePPE
Photo courtesy of Schneider Electric
©2008
4-18
Arc Blast With Circuit Breaker
©2008
4-19
Comparison of Blasts
Both Blasts: 480 Volts, 30,000 Amps
Uncontrolled Blast Circuit Breaker BlastCircuit opened in 330 milliseconds
Incident energy = 30 calories per cm2
Circuit opened in 8 milliseconds
Incident energy = .30 calories per cm2
Circuit breaker = energy reduction factor of 100!
©2008
4-20
What is Lockout/Tagout?
Photo courtesy of Schneider Electric
©2008
4-21
The placement of a lockout device on an energy isolating device, in accordance with an established
procedure, ensuring that the energy isolating device and the equipment
being controlled cannot be operated until the lockout device is
removed.
Lockout
©2008
4-22
The placement of a tagout device on an energy isolating device, in
accordance with an established procedure, to indicate that the energy
isolating device and the equipment being controlled may not be operated
until the tagout device is removed.
Tagout
DANG
ER
©2008
4-23
1910.147 Versus 1910.333
1910.147 1910.333Equipment that might unexpectedly energize
When
Who
Verifi-cation
Energized circuits
Authorized person Qualified person
Verifies isolation and de-energization
Tests for energized condition due to inadvertant voltage or voltage backfeed
©2008
4-24
Achieving an Electrically Safe Condition
©2008
4-25
Warnings and Signs
Slide courtesy of Schneider Electric
Illustrates minimum requirement.This is an example, not a
recommendation.
Illustrates minimum requirement.This is an example, not a
recommendation.
©2008
4-26
Warnings and Signs
Slide courtesy of Schneider Electric
©2008
4-27
The Importance of PPE
©2008
4-28
S a m p l e O n l y
Selecting PPE
OutputCategory PPE
0
1
2
3
4
Untreated cotton
FR shirt and FR pants
Cotton underwear plus FR shirt & FR pants
Cotton underwear plus FR shirt & FR pants plus FR coverall
Cotton underwear plus FR shirt & FR pants plus double layer switching coat and pants
Incident Energy
(Cal/cm2)
N/A
4
8
25
40
©2008
4-29
Photo courtesy of Schneider Electric
PPE—Hand and Arm Protection
©2008
4-30
Photo courtesy of Schneider Electric
PPE—Face, Hands, Arms, Torso
©2008
4-31
Photo courtesy of Schneider Electric
PPE—Face, Hands, Arms, Torso
©2008
4-32
Control Summary
©2008
4-33
Electrical Controls—Case 1
©2008
4-34
Electrical Controls—Case 2
Photo Source: NIOSH Safety and Health for Electrical Trades
©2008
4-35
Electrical Controls—Case 3
Photo Source: NIOSH FACE Case 03NE022
©2008
4-36
Electrical Controls—Case 4
Photo Source: NIOSH FACE Case 03NE022
©2008
4-37
Planning for Your Small BusinessAction Potential
BarriersOvercoming the Barriers
