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metallic conduit or equivalent. Shielding should be electrically continuous its length. The
shielding should be connected to the welding power source so that good electrical contact
is maintained between the conduit and the welding power source enclosure.
2) Maintenance of the arc welding equipment
The arc welding equipment should be routinely maintained according to the
manufacturer’s recommendations. All access and service doors and covers should be
closed and properly fastened when the arc welding equipment is in operation. The arc
welding equipment should not be modified in any way, except for those changes and
adjustments covered in the manufacturer’s instructions. In particular, the spark gaps of arc
striking and stabilizing devices should be adjusted and maintained according to the
manufacturer’s recommendations.
3) Welding cables
The welding cables should be kept as short as possible and should be positioned close
together, running at or close to the floor level.
4) Equipotent bonding
Bonding of all metallic components in the welding installation and adjacent to it should be
considered. However, metallic components bonded to the word piece will increase the risk
that the operator could receive an electric shock by touching these metallic components
and the electrode at the same time. The operator should be insulated from all such bonded
metallic components.
5) Earthling of the work piece
Where the work piece is nor bonded to earth for electrical safety, nor connected to earth
because of its size and position, for example ships hull or building steelwork, a connection
bonding the work piece to earth may reduce emissions in some, but not all instances. Care
should be taken to prevent the earthling of the work piece increasing the risk of injury to
users, or damage to other electrical equipment. Where necessary, the connection of the
work piece to earth should be made by a direct connection to the work piece, but in some
countries where direct connection is not permitted, the bonding should be achieved by
suitable capacitance, selected according to national regulations.
6) Screening and shielding
Selective screening and shielding of other cables and equipment in the surrounding area
may alleviate problems of interference. Screening of the entire welding installation may
be considered for special applications.