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					          ELC 119R-S
  Electrical Safety Refresher
  for Subcontract Electrical
            Workers


ELC 119R-S                      1
               Outline
Introduction
1   Shock and Arc Flash
2 Electrical Hazard Mitigation
3 Technical work documentation (TWD)
4 Safe switching procedures
5 Wrap-Up



ELC 119R-S                             2
               Introduction
 ~ 300 workplace electrocutions annually
 Estimated 20,000 shocks for every
  electrocution
 ~ 4000 injuries annually requiring days away
 ~3600 disabling electrical contact injuries
  annually
 10-15 workers hospitalized daily with
  electrical burns
 4-year average of 23 electrical events at SNL
ELC 119R-S                                   3
 Most Common Electrical Events at
             SNL
 Short circuit of energized parts to ground
 Workers shocked from approaching nearer
  than a safe distance from exposed live
  parts
 Workers shocked from faulty equipment
 Workers shocked from
  plugging/unplugging equipment

ELC 119R-S                                 4
      Module 1: Shock and Arc Flash

The passage of electric current through the
body from contact with an electric circuit (conductors).
Exposure to electrical energy may result in no injury
at all or may result in devastating damage or death.

Electrocution is death by electrical energy resulting
from the passing of a high magnitude electric current
through the body


ELC 119R-S                                                 5
                                                           5
  Why Are We Susceptible to Injury by
           Electric Shock?
A. Our highly developed nervous system
   makes us extremely sensitive to even very
   small electric currents.

B. The passage of current through the body
   results in heating of tissue

Each of these interactions has serious
consequences.
ELC 119R-S                                     6
                                               6
     Effects of Current on the Body
            Current Value                   Effects
< 1 ma                      Barely Perceptible
1-5 ma                      Perceptible shock, reflex actions
5 ma GFCI trips             Accepted as maximum harmless
                            current
6-10 ma                     Painful shock, victim can “let-go”
10-20 ma                    Painful shock, victim can not let go
50-100 ma                   Ventricular Fibrillation possible
100-200 ma                  Ventricular Fibrillation likely
200 ma                      Severe burns, severe muscular
                            contractions, chest muscles clamp
                            the heart and stop it for the
                            duration of the shock.
833 ma                      Current used by 100 watt light bulb

ELC 119R-S                                                        7
 Effect of Current Passing Through
              the Body
 Current can confuse or damage nerve
  control centers of lungs and heart
 Heat damage caused by dissipation of
  energy- body acts as a resistor.




ELC 119R-S                               8
ELC 119R-S   9
Unfortunate mouse suffers a fatal phase to phase shock




ELC 119R-S                                           10
                 Factors Affecting Shock
                 Remember Ohm’s Law: E=IR
   Current: most important factor, though directly
    determined by voltage and body resistance.


   Path of current: greater chance for survival
if current passes through extremities only


   Duration of Shock: according to IEEE std. 80,
    the maximum safe duration can be determined
    by using: t (seconds) = .116/(V/R)
    ELC 119R-S                                        11
                     Example
If an electrician gets a shock from a 277 volt light
fixture, would he/she get “stuck” on the circuit? Let’s
assume the worker was sweating and use a
resistance value of 10,000 ohms.

I =E/R
I = 277/10,000
I = .0277 amps or ~28 ma


 ELC 119R-S                                           12
                     Is He/She Stuck?
            Current Value                     Effects
<1 ma                         Barely Perceptible
1-5 ma                        Perceptible shock, reflex actions
5 ma GFCI trips               Accepted as maximum harmless
                              current
6-10 ma                       Painful shock, victim can “let-go”
10-20 ma                      Painful shock, victim can not let go
50-100 ma                     Ventricular Fibrillation likely
100-200 ma                    Ventricular Fibrillation occurs
200 ma                        Severe burns, severe muscular
                              contractions, chest muscles clamp
                              the heart and stop it for the
                              duration of the shock.
833 ma                        Current used by 100 watt light bulb


ELC 119R-S                  YES!                                   13
              Example continued
Let’s also assume that the path of the current
is hand to hand. How long does this person
have before the shock could be considered
fatal?

T = .116/(V/R)
T = .116/(277/10,000)
T = .116/.0277
T = 4.18 seconds!
 ELC 119R-S                                      14
             Voltage Thresholds
 OSHA set threshold for hazardous energy
  at 50 volts
 Hazard from applications lower than 50
  are usually thermal not shock: batteries,
  super capacitors, etc.
 At levels greater than 600 V, skin is
  usually penetrated driving resistance
  down.
ELC 119R-S                                    15
             Entry and exit wounds



ELC 119R-S                           16
        Rescuing and Treatment
Step 1 – Check to see that the area is safe to enter
Step 2 - Call 911 immediately
Step 3- Rescue the victim with an insulated device
         (hot stick, rope, dry wood, etc)
Step 4 – Begin CPR
Step 5 - Continue resuscitation
Step 6 - Get medical attention for the victim


 ELC 119R-S                                      17
               II    Arc Flash
A release of thermal energy from an electric arc
by the vaporization and ionization of materials,
reaching temperatures up to 35,000 °F.
Exposure to these extreme temperatures both
burns the skin directly and causes ignition of
clothing.

(2004 NFPA 70E)
ELC 119R-S                                         18
                 Nature of the Arc
   Arc results from passing of current through air
   Terminals vaporize and serve as conductive
    medium for ionized gasses
   Flash can extend further than 10’ from the
    source
   Pressure wave caused by rapid expansion of
    gases with flying molten materials and shrapnel
   The blast can destroy structures, and knock
    workers from ladders or across a room. The
    blast can rupture eardrums and collapse lungs.
    ELC 119R-S                                   19
       Nature of the Arc continued




ELC 119R-S                           20
    Three Factors Affecting Arc
             Energy
 Available short circuit current
 Duration of the arc
 Distance from the arc




ELC 119R-S                          21
             Burns From the Arc
 First degree: surface only. Skin is usually
  red and tender
 Second degree: blistering of the skin. Most
  painful
 Third degree: complete destruction of the
  skin with charring of tissue. Most
  dangerous –susceptible to infection. Skin
  can not heal itself.
ELC 119R-S                                  22
    First Degree Burns from a 480
                Fault




ELC 119R-S                          23
    Second Degree Burns from the
          same 480 Fault




ELC 119R-S                         24
         Effects of the Arc- Burns
Arcs have ignited clothing 10’ from the arc and can be fatal
when within a few feet
                          Burn Injury - Probability of Survival

                        100%
                        80%
           % Survival




                                                                 25% Body Burn
                        60%
                                                                 50% Body Burn
                        40%                                      75% Body Burn
                        20%
                         0%
                               20-29.9 30-39.9 40-49.9 50-59.9
                                   Age Range - Years

  ELC 119R-S                                                                     25
 Accelerator Flash Incident

             On October 11, 2004, at approximately 11:15 am,
    a subcontractor electrician working at an Accelerator Center received
             serious burn injuries requiring hospitalization due
              to an electrical arc flash that occurred during the
               installation of a circuit breaker in an energized
                          480-Volt (V) electrical panel.




ELC 119R-S                                                                  26
Arc flash 2004
  ELC 119R-S     27
ELC 119R-S   28
ELC 119R-S   29
        Importance of FR Clothing
              60/40 blend here




ELC 119R-S                          30
From the Type A Investigation…
Description of Injuries:

Electrician received third degree burns on the
face, chest, and legs and second degree burns
on the arms, involving approximately 50% of his
body. Because of the seriousness of his
condition, the Board was not able to interview
him.
ELC 119R-S                                  31
          Module 2: Electrical Hazard
                  Mitigation

1. Plan your work
2. Analyze/identify the hazards
3. Control the hazards
4. Perform the work
5. Improve the process for the next operation




 ELC 119R-S                                     32
        1910 CFR 851 and NFPA 70E
   All Department of Energy Facilities are
    contractually required by law follow 10
    CFR 851- Worker Safety and Health
    Protection Plan
   851.23(a)(14) requires contractors to
    comply with NFPA 70E as a baseline.
   70E is the industry standard for
    addressing electrical hazards in the
    workplace
   Applying 70E standards nothing more
    than using integrated safety
    management
    ELC 119R-S                                33
                 TURN IT OFF!
   Energized work no longer allowed at SNL
    unless:
    “de-energizing introduces additional or increased
      hazards or is infeasible due to equipment
      design or operational limitations” 70E 110.8.A.1

    Most hazards can be controlled by insulating,
    guarding, or by simply working de-energized


ELC 119R-S                                           34
     Electrically Safe Work Condition
First priority is to de-energize
1. Review safety plan
2. Inspect equipment, disconnect energy sources, and lock and tag
   energy sources.
3. Post barricades and signs to establish the limited approach and flash
   protection boundaries.
4. Open enclosure, identify shorting devices, and discharge energy-
   storage devices if applicable.
5. Perform Zero Energy verification Test
6. Complete work
7. When the work is completed, test circuits, remove tools, and test gear,
   perform final check, and close enclosure
NOTE: Equipment is not considered de-energized until locked out and
   verified
     ELC 119R-S                                                          35
                      Energized Work -
      provided justification requirements (slide 34) are met
   Strict requirements addressing worker
    qualifications:
        Qualified Person: One who has the skills and knowledge related to
         the construction and operation of the electrical equipment and
         installations and has received safety training on the hazards
         involved (Electrical Safety in the Workplace, 2004).
   Energized work must be authorized by Senior
    Manager Facilities Engineering- see your contract
    Sandia delegated representative (SDR)
   Shock and Flash Hazard Analyses required. This
    can be accomplished using the table on slide 44.
    Remember 2 different hazards- shock and flash
    ELC 119R-S                                                          36
                 Shock Hazard Analysis
 Required ANYTIME a worker crosses the
  Limited Approach Boundary to exposed live
  parts
 Must determine approach boundaries
  (Limited and Restricted) and required shock
  PPE (usually gloves and insulated tools)
 Shock PPE required ANYTIME a worker
  crosses the Restricted Approach Boundary

    ELC 119R-S                                  37
    Shock Approach Boundaries
   Limited Approach Boundary (LAB)
     Level II authorization required
     Only qualified workers may cross *
     Boundary must be physically established

   Restricted Approach Boundary (RAB)
       No unqualified workers
       Shock PPE required
       Shock PPE mainly consists of insulating gloves and tools
   Refer to slide 44 for LAB and RAB
    approach distances and required PPE.
ELC 119R-S                                                         38
             Flash Hazard Analysis

 Required ANYTIME a worker crosses the
  flash protection boundary (FPB)
 Must determine the Flash Protection
  Boundary and the PPE required for
  crossing this boundary
 PPE and distances determined from table
  slide 44

ELC 119R-S                                  39
             Arc Flash Protection
• PPE and flash protection boundary (FPB) in
  CSSP will match that of arc flash hazard
  (AFH) label on equipment
• If the electrical equipment is not provided with
  an AFH warning label, PPE and FPB in CSSP
  will be determined using the table in slide 44.




ELC 119R-S                                           40
Exposed Live Part
                    Limited Approach Boundary (shock)
                    Level II authorization required
                    Only qualified workers may cross – unqualified workers
                    may cross if escorted by qualified worker and made
                    aware of the hazards
                    Boundary must be physically established




                      Flash Protection Boundary
                      Distance and PPE determined from table in slide 42
                      PPE required of ANYONE inside this boundary




                       Restricted Approach Boundary (shock)
                       No unqualified workers
                       Shock PPE required
                       Shock PPE mainly consists of insulating gloves and
                       tools
ELC 119R-S                                                          41
    Hazard Risk Categories (HRC)
   HRC 0: Single phase circuits operating at 50-208 volts
   HRC 1&2: Three-phase circuits operating between 120
    and 600 volts
   HRC 3&4: Three-phase service entrance equipment and
    switchgear operating between 120 and 600 volts,
    excluding those systems with a RED, Level V Arc Flash
    Hazard label.




ELC 119R-S                                               42
    Hazard Risk Categories (HRC)
   Hazard Risk Above Forty Calories: All equipment
    identified with a Level V (red) Arc Flash Hazard label
   Hazard Risk Greater Than 600 volts: Obtain flash
    hazard analysis.
      Exception: HRC 2 PPE shall be worn In 15 kV
       manholes. Head, face and glove protection may be
       removed during cable terminations if no other work is
       being performed in the manhole.




ELC 119R-S                                                     43
              Boundary and PPE Table
                                                   Flash Boundary                          Required flash PP
                                      HR                                                                                               PPE
   Equipment Class
                                       C                                                                                               Code
                                                        LAB, RAB                         Required shock PPE
                                                                                                      EWC
                                                             4’
       208/240 1-ø                     0                                                                                               Green
                                                      3’ – 6”, contact                  Class 0 gloves with leather
                                                                                       protectors and insulated tools
                                                                                             EWC + accessories
   120/240, 277/480
                                                              6’
   3-ø non service                    1, 2                                                                                              Blue
                                                             4’, 1’                     Class 0 gloves with leather
      entrance                                                                         protectors and insulated tools
                                                                                                       ISC
  120/240, 277/480                             Contact FMOC project lead
                                       3                                                                                               Yellow
3-ø service entrance                                     4’, 1’                         Class 0 gloves with leather
                                                                                       protectors and insulated tools
                                                                                                      ESC
                                               Contact FMOC project lead
  120/240, 277/480
                                       4                                                                                               Orange
3-ø service entrance                                         4’, 1’
                                                                                        Class 0 gloves with leather
                                                                                       protectors and insulated tools
 Equipment labeled
                                                Contact SDR, CO, or PM                  Contact SDR, CO, or PM for
  greater than 40                     NA
                                                     for assistance                             assistance
                                                                                                                                        Red
calories or 600 volts
EWC: FR long sleeve shirt (min arc rating = 8) worn over untreated cotton t-shirt with FR pants (min arc rating = 11, safety glasses
Accessories: hard hat w/FR rated face shield, hearing protection, and leather boots or shoes
ELC 119R-S
IWC: EWC + accessories + FR coveralls (min arc rating = 25) and double –layer switching hood.                                                   44
ESC: 40-calorie switching suit w/rated hood and gloves, leather boots and shoes.
          Example Arc Flash Labels
              Level I (HC-0) Label                         Level II (HC-1 and HC-2) Label
                 WARNING                                              WARNING
          ARC FLASH & SHOCK HAZARD                             ARC FLASH & SHOCK HAZARD

 BUILDING    867        LOCATION      PANEL MSB1      BUILDING    752         LOCATION       PANEL 1BH1


      INCIDENT                        HAZARD
  ENERGY @ 18”
                   <2   cal/cm2
                                    CATEGORY
                                                 0         INCIDENT
                                                                        6.9   cal/cm2
                                                                                            HAZARD
                                                                                                       2
                                                       ENERGY @ 18”                       CATEGORY


   APPROACH                                             APPROACH
   BOUNDARY         3     ft        PPE LEVEL    I                      3.8     ft        PPE LEVEL    II
                                                        BOUNDARY


 SOURCE     TF-0867-1             MAXIMO              SOURCE     TF-0752-1              MAXIMO

                                    DATE   10/05/07                                       DATE   10/05/07




ELC 119R-S                                                                                                  45
         Electro-Magnetic Energy
   Whenever you have electric power, electric and
    magnetic fields will be generated.
   The electric field is often generated by the
    alternating voltage of the electrical system. The
    higher the voltage, the greater the electric field.
    Taken together, electric and magnetic fields are
    often referred to as electromagnetic radiation.
   The main effect of exposure to EME is heating of
    tissue and organs.
   There are rooftop antennas at Sandia that emit
    varying levels of EME so contact your ES&H
    coordinator before approaching them
ELC 119R-S                                                46
            Worker Responsibilities
 Familiarize yourself with procedures and
  work plans- CSSP
 Be aware of your surroundings
 Obey all warnings signs and regulations
 Always use proper PPE (slide 44)
 Stop work if an unsafe and/or unexpected
  condition arises
 Consider ALL electrical equipment energized
  unless locked out and verified de-energized
    ELC 119R-S                             47
              Worker Responsibilities
• Do NOT perform unjustified energized work
• Do not wear jewelry when performing energized
  work
• Report ALL accidents, regardless of severity to
  Safety Officer/Supervisor
• Immediately report to your supervisor, anyone
  known to be under the influence of drugs or
  alcohol
• Be aware of secondary hazards- beryllium,
  radiation, noise, etc
• Be responsible for your own safety!
 ELC 119R-S                                         48
             Planning Your Work
   Planning is a key element in performing work
    safely and is the first step in the ISMS process.
   OSHA and 70E require a job briefing be held
    before any electrical work operation begins.
     Allpersonnel involved in the job shall be briefed on
      the safety concerns, energy source controls and
      precautions regarding their assignments.
     Should work conditions change or unanticipated
      hazards appear, additional briefings should be held.
   Planning must be documented!

ELC 119R-S                                                   49
      Planning Your Work continued
   Consider ALL hazards
     When    changing a ballast, what hazards are
      involved besides electricity and working from
      heights?
     Is there an asbestos issue?
     Is the fixture in an area known to have
      dangerous levels of Beryllium?
     How about radiation?



ELC 119R-S                                            50
        Planning Your Work continued
• The meeting must cover the following
  questions:
   – Do I thoroughly understand the job?
   – Do I thoroughly understand my role in the job?
   – Am I aware of all the hazards I may encounter?
   – Am I knowledgeable of all the safety rules and
     required personal protective equipment that
     apply to the job?


ELC 119R-S                                            51
             Performing Your Work
   All circuits must be considered energized until
    LOTO’d and verified de-energized
      Several  events at SNL have been the result of failure to
       verify de-energized
   Performance of the 0 energy verification still
    requires PPE and boundary establishment (slide
    44)
   Do you have to do this hot?
   Physically establish the limited approach boundary
    (slide 44)
      Boundary must keep unqualified workers out of area
      Boundary must warn workers of the hazards inside the
       area
    ELC 119R-S                                                     52
                 Performing Your Work
   Wear the appropriate PPE
        Shirt must be buttoned and sleeves rolled down
        Flash PPE is required when inside the flash protection boundary
         (slide 44)
   Crossing the restricted approach boundary requires gloves
    and insulated tools (slide 44)
        Maintain your gloves
        Are they out of testing date requirements?
   Use the right tools for the job
        Is you meter rated for the task?
        Several events at SNL have occurred due to use of an inappropriate
         meter
   Do not deviate from job plan.
        If work outside of scope is required stop and re-evaluate with all
         involved co-workers.
    ELC 119R-S                                                                53
                 Module 2 Conclusion
   Severe hazards associated with energized electrical
    work
   Energized work is now the exception- not the norm-
    Turn –it-off!
   NFPA 70E provides sound guidance for electrical
    safety in the workplace
   Applying the standard is basic ISMS- identify the
    hazard, control the hazard
   Remember there are two primary hazards (shock
    and flash) that must be analyzed and controlled
    independently
    ELC 119R-S                                      54
   Module 3: TWD Requirements
Q: What is considered energized work at SNL?
A: Any activity inside the Limited Approach
  Boundary (LAB)
   Crossing the LAB for ANY reason must meet
  the 70E justification requirements of 110.8.A.1
  (slide 35)
  ALL energized work requires a technical work
  document
Why? This should be your first question when
 asked to work energized.

ELC 119R-S                                          55
    Contract Specific Safety Plan
              (CSSP)
 The CSSP is the required technical work
  document for all energized work at SNL
  performed by a facilities subcontractor
 The CSSP must incorporate the required
  energized work permit elements required
  in NFPA 70E 130.1B2


ELC 119R-S                                  56
              Content of the CSSP
1. A description of the circuit/part to be worked on and
   its location
2. Justification of why the work must be performed
   energized. Remember that some troubleshooting
   could be accomplished with an Ohm meter.
3. A description of safe work practices to be employed
   (second person, safety watch, Barriers, etc)
4. Results of the shock hazard analysis (voltage the
   employee(s) will be exposed to) – slide 44
5. Determination of shock approach boundaries (LAB,
   RAB, PAB) using table slide 44
 ELC 119R-S                                           57
      Content of the CSSP continued
6. Results of the flash hazard analysis (determination of
    the Flash Protection Boundary and the caloric
    exposure based on table slide 44
7. The necessary personal protective equipment-
    shock and flash
8. Means used to restrict access of unqualified
    personnel to the area (chains, flagging, signage, etc)
9. Evidence of completion of a pre-job briefing including
    topics covered- checklist
10. Energized work approvals (workers, Managers,
    Senior Managers)
  ELC 119R-S                                           58
               Insulated Tools
   Insulated tools, rated for the system voltage, are
    required when contacting any energized
    component. Insulated tools should be listed
    under # 3. Ground hooks shall also be listed
    here.

   If the insulated tool can prevent the user from
    crossing the restricted approach boundary and
    flash protection boundary, PPE will not be
    required (except safety glasses).
ELC 119R-S                                               59
         Module 4 Safe Switching
              Procedures
   Three hazards associated with switching
    breakers or disconnects
     Shock
     Explosion
     Arc    flash/blast




ELC 119R-S                                    60
                 Shock
 Rare when switching because cover
  should be in place.
 Remember shock boundaries
 30,000 non-fatal shocks each year in the
  workplace…
 247 died from electrocution in
  2006…down from 251 in 2005.

ELC 119R-S                                   61
              Breaker Explosion

   Counterfeit Products
     Sub-standard
      components
     No NRTL listing

   Improper Sizing
     Improperly  rated for
      available fault current




ELC 119R-S                        62
             Arc Flash - 2006




ELC 119R-S                      63
             Operating Breakers and
                  Disconnects
   Use one hand when possible.
   For side-handled switches, stand as far away
    to the side as possible to operate the switch.
   For panel-mounted breakers, do not stand in
    front of the panel when operating the
    breaker.
   Do not expose unprotected portions of the
    body/face to the potential blast.
ELC 119R-S                                       64
 Review – Switching Operations
   Disconnect Rating               Required PPE (Hazard
                                        Category)
Up to and including 60 amps                        HC 0 *
(< 600 volts)

>60 up to and including 200                        HC 2 *
amps (< 600 volts)

> 200 amps (< 600 volts)              Must be analyzed by a
and all > 600 volts                  qualified person. Contact
                                        electrical safety for
                                             evaluation.
               •Arc flash labels supersede this table
               •reference slide 44 for specifics
ELC 119R-S                                                       65
             Module 4 Conclusion
   Switching can be hazardous
   Wear appropriate PPE
   Obtain AIC and clearing times prior to switching
   Never switch breakers or disconnects under trip
    conditions - call facilities
   Never close a breaker or disconnect if
    uncomfortable
   Use Left hand rule to keep body away from
    disconnect when closing
ELC 119R-S                                             66
              Course Wrap-Up
   You seldom get a second chance with electricity
   Most electrical accidents are caused by unseen or
    unanticipated hazards
   Take your time!
   Never deviate from procedures
   If circumstances or conditions change- STOP and
    re-evaluate
   Work on energized equipment is restricted at SNL
   Maintain tools, test equipment, and PPE
   Never rely on others for your safety

ELC 119R-S                                         67
             Thanks for Viewing

                    Questions:
              Greg Kirsch at 845-9497
             Mark McNellis at 845-4895
             Marc Williams at 845-8795



ELC 119R-S                               68

				
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