KMU SUBSTATION WORKSHOP

Transcription

1 Rick Aguilar, Director of Job Training & Safety KMU SUBSTATION WORKSHOP JUNE 29-30, 2016 OTTAWA, KS

2 Hazards & Safety Rules Qualified Personnel & Task-Based Hazard Mitigation Worksite Applications & Considerations Electric Arc Protection FACE Reports & Lessons Learned Electrical Principles Ohm s Law Circuit review

3 HAZARDS & SAFETY RULES

4 Re-energized line(s) Induced voltages & currents Magnetic induction Capacitive induction Step potential Touch potential

5 Magnetic voltages Capacitive induction

6 Equal to the difference in voltage, given by the voltage distribution curve, between two points at different distances from the electrode

7 Voltage resulting from touching a conductive object that is connected to a remote energized component

8 OSHA Regulations (n)(2) General. For any employee to work transmission and distribution lines or equipment as deenergized, the lines or equipment shall be deenergized under the provisions of paragraph (m) of this section and shall ensure proper grounding of the lines or equipment as specified in paragraphs (n)(3) through (n)(9) of this section (n)(3) Equipotential zone. Temporary protective grounds shall be placed at such locations and arranged in such a manner that the employer can demonstrate will prevent each employee from being exposed to hazardous differences in electric potential.

9 Standards IEEE Std NESC C Placement of grounding sets for employee protection

10 512 Substations General Rules Working in an Energized Substation Hazardous Energy Control (LOTO) Batteries Circuit Breaker Maintenance & Repair Working in Transformer Tanks & Vessels Work in Manholes & Vaults Splicing & Terminating Vault/Manhole Rescue *Rev. 15, 2012

11 507 Overhead Lines and Equipment Working on De-energized Lines and Equipment Stringing or Removing De-energized Conductors Stringing Adjacent to Energized Lines Grounding General Equal Potential Grounding 509 Underground Lines and Equipment Work on De-energized Cables Grounding URD Circuits *Rev. 15, 2012

12 *Table Minimum Depth of Clear Working Space at Electric Equipment, Over 600 V Nominal voltage to ground Minimum Clear Distance for Condition 1,2 Condition A Condition B Condition C m ft m ft m ft V V V-25 kv Over kv Above 75 kv APPA Safety Manual 15 th Ed. pg. 233

13 Table R-6 Alternative Minimum Approach Distances for Voltages of 72.5 kv and less 1 Nominal voltage (kv) Phase-to-Phase Phase-to-Ground Distance Phase-to-Phase m ft m ft to Avoid Contact Avoid Contact to to to to to to

14 Table R-5 Altitude Correction Factor Multiply distances from Table R-6 with correction factor corresponding to altitude of work Altitude above sea level (m) 0 to to 1, ,201 to 1, ,501 to 1, ,801 to 2, ,101 to 2, ,401 to 2, ,701 to 3, ,001 to 3, ,601 to 4, ,201 to 4, ,801 to 5, ,401 to 6, Correction Factor

15 QUALIFIED PERSONNEL & TASK- BASED HAZARD MITIGATION

16 One who has received training in and has demonstrated skills and knowledge in the construction and operation of electrical equipment and installation and the hazards involved.

17 One who has the skill and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved. May be considered qualified with respect to certain equipment & method but still unqualified for others.

18 Employer must provide the employee in charge with all available information that relates to the determination of existing characteristics and conditions under (a)(4) and (d): Employer shall ensure employee in charge conducts a job briefing Information on existing characteristics Information about existing conditions (c)(1)(i) & (a)(1)

19 Employer to employee in charge, employee in charge to coworkers Hazards associated with the job Work procedures involved Special precautions Energy-source controls Personal protective equipment requirements (c)(1)(ii) & (a)(2)(b)

20 Number of briefings At least one before each day or shift When there significant changes (c)(3) & (a)(2)(c)

21 Short discussion Satisfactory if the work involved is routine Detailed discussion If work is particularly hazardous, or If employees cannot be expected to recognize and avoid the hazards involved

22 Isolate not able to contact energized part Insulate same principle used with energized work

23 Magnetic voltages Capacitive induction

24 Key is to place worker in parallel with low resistance path to shunt dangerous current & limit voltage across worker. Return path considerations System neutral Ground rod Approved ground clams, jumpers #2 copper, clean surfaces

25 Subtitle ELECTRIC ARC PROTECTION

26 Outer layer of clothing must be arc-rated for incident energy exceeding 2.0 cal/cm 2 Arc-rated protection must cover entire body, with certain exceptions: Protection for hands (rubber gloves with protectors or, for exposures 14 cal/cm 2, heavy-duty (12oz) leather work gloves) Protection for feet (heavy work shoes or boots) Protection for the head under certain conditions (l)(8) & (g)

27 Federal Register pg (l)(8) & (g)

28 Head when incident energy is < 9 cal/cm 2 (single phase), or < 5 cal/cm 2 for other exposures Hands when wearing rubber gloves and protectors Feet when wearing heavy leather boots

29 Hazard Risk Category 0 Hazard Risk Category 1 Hazard Risk Category 2 Hazard Risk Category 3 Hazard Risk Category 4

30 100% cotton long sleeve shirt Long pants Safety glasses Hearing protection Leather and insulated gloves (as required) Leather work boots

31 4+ cal long sleeve shirt & long pants (or) coveralls Hardhat Safety glasses Arc rated face shield Hearing protection (inserts) VR gloves Leather gloves Leather work boots

32 8+ cal long sleeve shirt & long pants (or) coveralls Hardhat Safety glasses Arc rated face shield Hearing protection (inserts) VR gloves Leather gloves Leather work boots

33 25+ flashsuit w/ hood over long sleeve shirt and long pants Safety glasses Arc rated face shield Hearing protection (inserts) VR gloves Leather gloves Leather work boots

34 40+ flashsuit w/ hood over arc-rated FR long sleeve shirt and long pants Safety glasses Arc rated face shield Hearing protection (inserts) VR gloves Leather gloves Leather work boots

35 Layering Outer layers must be flame resistant Under layers must be non-melting Fit Clothing shall fit properly (loose), w/ least interference Coverage Clothing must cover potentially exposed areas (wrist, neck) Care & Maintenance Inspect before use Launder according to mfg s instructions *Photo courtesy of Salisbury

36 Equipment exposed to electric arcs must pass drop test post-exposure No requirement to pass an arc rating test

37 Assess worksite for hazards Determine appropriate controls May use isolation, insulation, and equipotential zones Ensure no contact with equipment and ground rod

38 Stringing adjacent to energized lines and equipment Placement of tools and materials Worksite access control Ensure no contact with equipment and ground rod

39 FACE REPORTS & LESSONS LEARNED

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43 Inspections and P.M. need to be completed and are critical safety element for personnel and facilities Control access and ensure personnel are qualified for tasks Communicate PPE & MAD requirements with exposed workers

44 Rick Aguilar, CUSP, PHR Director of Job Training & Safety Kansas Municipal Utilities 101 ½ N. Main McPherson, KS (316) Serving municipal utilities for 85 years