Disaster prevention - Edwards @ Wiki

7 Disaster prevention against welding work

7.1 Disaster caused by welding work: Omission

7.2 Disaster by electric shock
7.2.1 Measures

• Measures Excerpt
  • Use welding machine with the highest no-load voltage
  • Connection of grounding wire to outer casing of welding machine
    • Hull color: green
    • Conductor diameter: 14 [mm^{2}]
    • Earth resistance: 100 [\Omega] or less
  • Addition of electric shock prevention device
  • Use of insulated type welding rod holder
    • Inspection of deterioration and breakage of insulation part
  • Reliable insulation against conductive parts around the welding machine
  • Reliable connection of welding machine and cable for continuing metal base contact between welding machine
  • Secure wear of protective equipment
    • Leather gloves: Select and use more than JIS T 8133 conforming standard
  • Firm wear of clothes
  • Other measures Excerpt
    • Stop the power supply of the welding machine against work interruption
    • Selection of supervisors in addition to avoiding independent work in narrow areas
    • Turn off the power to the electric shock accident and contact the fire department in addition to the first aid

7.3 Disaster summary due to arc light
7.3.1 Ark light disaster

• Light source due to arc light
  Measures to prevent injuries by strict light blocking
  • Visible ray
  • Ultraviolet
  • Infrared

7.3.2 Protection against injury and illness

• Selection of proper light shielding standard
  • According to JIS T 8141 provision
  • Selection of light shielding plate
    For use with a light block number no less than about 10,
    Shading method with a combination of light shielding plates less
    than single light shielding number is recommended
    • N: Single shade number
    • n_{1} & n_{2}: Shading index number of each plates
      N = (n_{1} + n_{2}) - 1
    • Note: EX
      10 = (8 + 3) -1
      10 = (7 + 4) -1

7.4 Disaster due to fire
7.4.1Disaster Summary

• Measures against spattering and scattering of slag in welding

• Confirmation of fire after work
  EX: Confirmation time after completion of work: 30 [min]

7.5 Disaster due to fire: Omission