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  • ARC FLASH HAZARD OVERVIEWPresented August 13, 2015WWOA Lake Michigan Districtby Mead & Hunt, Inc.

  • ARC FLASH EXPERIENCE

    Christopher J. DeWaal, MS, MEM, PE, LEED AP, HACCP How did I get involved? A client had an electrical incident

    that resulted in injury in 1998 and I was asked to help make their work environment safer.

    Engineers Thought Process: Will it work? Can we afford it? Safety . . . ? This is the law! Wisconsin Administrative Code

    Chapter A-E 8.

  • COST OF UNSAFE SYSTEM

    Liability Costs 1999 Case Study by EPRI for CapSchell put the cost per

    incident (death) at $15.75 million 1998 National Electrical Contractors Association study put

    the cost per incident (injury) at $6 million Lost time, medical bills, lawyers fees

  • SO WHAT?

    How common are electrical accidents?According to : NFPA 70E-2004, of the 350 Deaths in 2003

    because of electricity, 50% were by arc flash CapSchell, there are 5-10 arc flash events

    every day in the US, resulting in 1-2 deaths per day

    NFPA 70E-2012, more than 2000 people are admitted to burn centers per year because of arc flash

  • WORKPLACE FATALITY STATISTICS

  • ELECTRICAL CURRENT EFFECTS ON THE BODY

    Estimated Effects of 60 Hz AC Currents Shock

  • WHAT IS ARC FLASH?

    It is not electrocution or shock. Arc Flash is the energy produced

    in an electrical circuit or electrical piece of equipment when an arc is produced.

  • WHAT CAUSES ARC FLASH?

    Workers tools in contact with live parts Squirrel between transformer bushings Other conductive material in area

  • ARC FLASH EFFECTS

    According to Bussmann research, a fault producing 41 MVA will result in a temperature of 35,000 degrees F and up to 2,000 lbs./sq.ft. of pressure Surface of the Sun: 5k 9k degrees F 3rd Degree Burn: 155-175 degrees F for 1

    second Eardrum Rupture: 720 lbs./sq.ft.

  • ELECTRICAL SAFETY RULES

    NFPA 70E Standard for Electrical Safety Requirements for Employee Workplaces - 2015 Installation Methods Safe Usage of Electrical Equipment Lock-Out, Tag-Out Arc Flash Limits of Approach

  • WORKER SAFETY RESPONSIBILITY

    NFPA 70E 105.3 RESPONSIBILITY The employer shall provide the safety-related work practices

    and shall train the employee, who shall then implement them. Your safety is your responsibility!

  • ELECTRICAL SAFETY PROGRAM

    NFPA 70E 110.1 ELECTRICAL SAFETY PROGRAM Created and maintained by the employer Must consider condition of maintenance of electrical equipment

    and systems 110.1(B) Must provide an awareness of the potential electrical hazards

    110.1(C) Annex E gives examples

  • ELECTRICAL SAFETY PROGRAM

    NFPA 70E 110.1(G) RISK ASSESSMENT PROCEDURE1. Identify hazards2. Assess risks3. Implement risk control according to hierarchy of safety controls:

    1) Elimination2) Substitution3) Engineering Controls4) Awareness5) Administrative Controls6) PPE

  • ELECTRICAL SAFETY PROGRAM

    NFPA 70E 110.1(H) JOB BRIEFING Before starting each job, the employee in charge shall conduct a

    job briefing with the employees involved. NFPA 70E 110.1(I) ELECTRICAL SAFETY AUDITING Program audited every 3 years Field work (LOTO, Arc Flash) audited every year Audits shall be documented

  • TRAINING REQUIREMENTS

    NFPA 70E 110.2(A) & (B) The training requirements contained in this section shall apply to

    employees exposed to an electrical hazard when the risk associated with that hazard is not reduced to a safe level by the applicable electrical installation requirements.

    Training can be classroom, on-the-job or a combination. NFPA 70E 110.2(C) EMERGENCY RESPONSE TRAINING Employees responsible for responding shall be trained in CPR,

    AED and first aid. Training shall be verified annually and documented

  • QUALIFIED & OUTSIDE PERSONNEL

    Qualified Person (NFPA 70E, 110.2(D)(1)) NFPA 70E 110.3(A), (B) & (C) Host Employer: Must inform contract employers of known hazards covered

    by NFPA 70E, give information about the installation that the contractor needs to made the assessments covered by NFPA 70E and report observed violations of this standard by contract employees to the contract employer

    Contract Employer: Must inform contract employees of known hazards covered by NFPA 70E as directed by host, insure that contract employees follow the work practices required by NFPA 70E and the host employer, and report unique hazards or hazards not mentioned by the host employer to the host employer.

    All meetings must be documented.

  • NFPA 70E ARTICLE 120

    Verification of an Electrically Safe Work Condition 120.11. Determine all possible sources of electrical supply, check

    applicable, up-to-date drawings2. Open the disconnecting device(s)3. Visually verify operation of disconnecting device(s)4. Apply lockout/tagout devices (LOTO: 120.2 15 pages)5. Test each phase conductor or circuit part phase-to-phase and

    phase-to-ground6. Ground phase conductors if induced or backfed electrical

    energy could exist (120.3)

  • NFPA 70E ARTICLE 130

    Work Involving Electrical Hazards 130.2: Energized electrical conductors and circuit parts shall

    be put into an electrically safe work condition unless:1. De-energizing introduces additional hazards or increased risk

    (life support systems, emergency alarm systems, hazardous location ventilation), or

    2. Is infeasible in a de-energized state due to equipment design or operational limitations (diagnostics, testing, start-up, troubleshooting and work on circuits that form part of a continuous process).

  • NORMAL OPERATION

    130.2 (A)(4): Normal operation of electric equipment shall be permitted where all of the following conditions are satisfied:1. The equipment is properly installed.2. The equipment is properly maintained.3. The equipment doors are closed and secured.4. All equipment covers are in place and secured.5. There is no evidence of impending failure.

  • NFPA 70E ARTICLE 130

    130.2(B): Energized Electrical Work Permits are required when working within restricted approach boundary of exposed live parts that are not put into an electrically safe work condition or when the employee interacts with the equipment when it is not exposed, but a increased likelihood of injury from exposure to arc flash exists. 130.2(B)(3): Exception for testing, troubleshooting, voltage

    measuring, thermography, visual inspection, access to or egress from the area or general housekeeping by QUALIFIED PERSONS

  • NFPA 70E ARTICLE 130

    130.4: Approach Boundaries to Live Parts for Shock Protection Shock Protection Boundaries Limited and Restricted Approach

    Boundaries Limited Boundary - The closest an unqualified person can get to an

    exposed, energized circuit Restricted Boundary - Only qualified persons are allowed inside this

    boundary with proper PPE

  • APPROACH BOUNDARIES AC SYSTEMS

  • ARC FLASH RISK ASSESSMENT

    130.5 ARC FLASH RISK ASSESSMENT Shall be performed and shall:1. Determine if an arc flash hazard exists. If one does, the

    assessment shall determine appropriate safety-related work practices, arc flash boundary and appropriate PPE. (Table 130.7(C)(15)(A)(a))

    2. Be updated when a major modification or renovation takes place. It shall be reviewed at least every 5 years.

    3. Take into consideration the design of the OCPD, OCPD opening time and the condition of maintenance.

    The results of the assessment shall be documented.

  • ARC FLASH RISK ASSESSMENT

    130.5(B) - ARC FLASH BOUNDARY Distance from energized circuit where a worker could receive an

    incurable burn (1.2 cal/sq. cm.) 130.5(C) ARC FLASH PPE One of the following methods (but not both) shall be used for the

    selection of PPE:1. Incident Energy Analysis Method (Arc Flash Study)2. Arc Flash PPE Categories Method (NFPA 70E Tables)

  • INCIDENT ENERGY ANALYSIS METHOD

    1. Determine Energy Levels Short Circuit (SC) Study Power Protective Device Coordination (PDC) Study Time Arc Flash Hazard Analysis Power X Time = Energy

    2. Recommendations Made to Reduce Energy Levels

    3. Determine Appropriate Protective Equipment

    4. Other Benefits: One-lines, system health assessment, etc.

  • ARC FLASH PPE CATEGORIES METHOD

    Table 130.7(C)(15)(A)(b) for AC systems Gives PPE categories for different equipment pieces Need to know available short circuit current, device clearing

    times and working distances (How do you do this?) Table 130.7(C)(15)(B) for DC systems similar to AC

    systems Table 130.7(C)(16) for PPE Categories

  • ARC FLASH LABELS

    Equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures and motor control centers shall be labeled with the following:1. Nominal system voltage2. Arc flash boundary3. At least one of the following:

    a. Available incident energy / working distance or PPE category from NFPA 70E tables, but not both

    b. Minimum arc rating of clothingc. Site-specific level of PPE

  • ARC FLASH LABELS - EXISTING

  • PPE HARDHAT & FACESHIELD

    Hardhats w/ faceshield 8 -12 Cal/cm2 Ultraviolet (UV) Infrared (IR) PROTECTION

  • ARC RATED CLOTHING

    Coveralls (shown) Hooded Parkas Bib Overalls Lab Coats

  • ARC FLASH CLOTHING

  • INSULATED HAND TOOL REQUIREMENTS

    All tools must be marked with the international safety symbol for 1000 Volts

    All tools must state the rating of 1000V All tools must have