Dr. David Sweeting is working on an arc hazards guide with three parts. Part 1 deals with legal issues, part 2 is for workers, explaining what to do, and part 3 is for experts on arc hazard exposure. Safe Work Australia created model work health and safety regulations in 2011 that were legally binding in some states, except for electrical supply authorities. The regulations require identifying electrical hazards like electrocution, electric shock, and arcing hazards. They also require managing identified risks so far as is reasonably practical using a hierarchy of control measures, from elimination to substitution to engineering to administrative to personal protective equipment. "Operating work" involving energizing, de-energizing, connecting, and earthing equipment is permitted energized

1. UPDATE ON ARCING HAZARDS by Dr. David Sweeting Hon.F.I.E Aust Senior member IEEE Visiting Professor University of Wollongong Sweeting Consulting Pty Ltd © ACN 003 795 257 Sweeting Consulting Pty Ltd
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2. MY ACTIVITIES
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Working on an “Arc Hazards Guide”
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Aim
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Part 1 deal will “legal issues”
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Interpretation
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Part 2 is for a “worker”
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What to do
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Part 3 is for an “expert”
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Arc hazard exposure document © ACN 003 795 257 Sweeting Consulting Pty Ltd 2

3. SAFE WORK AUSTRALIA
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Tripartite body of government, unions and employers
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In 2011 Model Work Health and safety (WHS) Act
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In 2011 Model Work Health and Safety Regulations
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Legally binding in some states
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Except for “electrical supply authorities” © ACN 003 795 257 Sweeting Consulting Pty Ltd 3

4. REGULATION 34 REQUIRES EVERYONE TO IDENTIFY
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Reasonably foreseeable electrical hazards
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Electrocution (ventricular fibrillation)
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Electric shock (larger currents in body)
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Arcing hazards (currents in the vicinity)
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HV electric shocks turn into arcing hazards
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Related hazards
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Falling, Confined spaces, hazardous substances, Flammable combustible substances © ACN 003 795 257 Sweeting Consulting Pty Ltd 4

5. ARCING FAULT ELECTRICAL HAZARDS
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Contact with arc column (Very severe burns)
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Clothing ignition/melting (Very severe burns)
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Decaying plasma cloud (Severe burns)
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Electrode metal spray (eye, skin burns)
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Radiation (light) (Burns, T blindness)
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Pressure waves (lung damage)
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Falling, being struck (landing, physical)
© ACN 003 795 257 Sweeting Consulting Pty Ltd 5

6. REGULATION 35 REQUIRES MANAGEMENT OF THE RISKS
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So far as is reasonably practical (SFAIRP)
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This involves
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(1) Eliminate risks SFAIRP
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(2) Then Implement risk controls
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(3) Minimise risk SFAIRP
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Regulation 36 provides a list of how to minimise SFAIRP
© ACN 003 795 257 Sweeting Consulting Pty Ltd 6

7. HIERARCHY OF CONTROL MEASURES
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(1) Eliminate risk
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(2) Implement risk controls
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(3) Minimise risk
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(3.1) substitute with lesser risk
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(3.2) Isolate the hazard from the person
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(3.3) Use engineering controls
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Then (4.4) Use administrative controls
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Finally (4.5) Provide suitable PPE © ACN 003 795 257 Sweeting Consulting Pty Ltd 7

8. USA relative to AUSTRALIA
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Hierarchy of hazard controls
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Similar wording
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NFPA70 (wiring rules)
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Engineering controls
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NFPA70E (work procedures)
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Reliance on PPE
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Desire for PPE to cover
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Everything using NFPA70E or IEE1584 © ACN 003 795 257 Sweeting Consulting Pty Ltd 8

9. AS3000 CONSIDERS
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Ventricular fibrillation (Electrocution)
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Excessive surface temperatures
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Explosive gases and dust
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arcing hazards (NOT really)
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electric shock (NOT really) © ACN 003 795 257 Sweeting Consulting Pty Ltd 9

10. PROHIBITED ELECTRICAL WORK ON ENERGISED EQUIPMENT
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Exposed parts are energised until isolated
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Exposed HV until earthed after isolation
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Permits Testing to prove “NOT energized”
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Silent on “operating work”
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Many arcing faults occur during “operating work” © ACN 003 795 257 Sweeting Consulting Pty Ltd 10

11. PERMITTED ELECTRICAL WORK ON ENERGIZED ELECTRICAL EQUIPMENT
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Regulation 157 says this is:
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NOT allowed UNLESS
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Necessary for health and safety
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Necessary to do work properly
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Necessary for testing for “dead”
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No reasonable alternative
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For a supply authority © ACN 003 795 257 Sweeting Consulting Pty Ltd 11

12. SERIES OF REGULATIONS
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What you have to do WHEN
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Working on “energized electrical equipment” © ACN 003 795 257 Sweeting Consulting Pty Ltd 12

13. REGULATIONS SILENT ON “OPERATING WORK”
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Energize/de-energize
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(load make/break)
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(fault make/break)
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Connect/disconnect
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(isolating distance)
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Earth/de-earth
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(fault rated earthing equipment)
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(discharge rated earthing equipment) © ACN 003 795 257 Sweeting Consulting Pty Ltd 13

14. “OPERATING WORK” IS PERMITTED ENERGIZED WORK
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Interest of Health and safety
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Necessary
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No alternative © ACN 003 795 257 Sweeting Consulting Pty Ltd 14

15. “OPERATING WORK” REQUIRES
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All Procedures of permitted energized work
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Except a GPO or plug (Reg 146)
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AS3000 compliant switchgear (shock/arcing hazards) © ACN 003 795 257 Sweeting Consulting Pty Ltd 15

16. ASSIGNMENT OF WORK
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“Specified mandated de-energized work”
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“Specified permitted energized work”,
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“Electrical work without a specified process” © ACN 003 795 257 Sweeting Consulting Pty Ltd 16

17. ASSIGNED WORK CONTAINS
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“Mandated de-energized tasks” (MUTs) and,
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“Permitted energized tasks”, (PETs)
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Energized work procedures
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and within each task there are:
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Hazards that require identification,
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With control measures required for each hazard © ACN 003 795 257 Sweeting Consulting Pty Ltd 17

18. BASIC WORK PROCESS OF UN-ENERGIZED WORK
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Disconnect
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Isolate
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Test for dead
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Earth (HV)
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MANDATED UN-ENERGIZED WORK
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Remove earth (HV)
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Test Insulation
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De-Isolate
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Reconnect and Energize © ACN 003 795 257 Sweeting Consulting Pty Ltd 18

19. QUESTIONS © ACN 003 795 257 Sweeting Consulting Pty Ltd
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