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3. ELECTRIC ARC (MIG, TIG) WELDING
Complywithprecautionsin1above,andthissection.Arcwelding,properlydone,
is a safe process, but a careless operator invites trouble. The equipment carries
highcurrentsat significantvoltages.Thearcisverybrightandhot.Sparksfly,fumes
rise,ultravioletandinfraredenergyradiates,weldmentsarehot.Thewiseoperator
avoids unnecessary risks and protects himself and others from accidents.
3A) BURN PROTECTION
Comply with precautions in 2. The welding arc is intense and visibly bright. Its
radiation can damage eyes, penetrate lightweight clothing, reflect from light
colouredsurfaces, and burntheskinandeyes.Skinburnsresembleacutesunburn,
those from gas - shielded arcs are more severe and painful.
DON’T GET BURNED! COMPLY WITH PRECAUTIONS!
1) Protective clothing
Wear long sleeved clothing (particularly for gas shielded arc) in addition to
gloves,apronand shoes (2A). As necessary,useadditionalprotectiveclothing
suchasleather jacket orsleeves,flameproofapron,and fire-resistantleggings.
Avoid outer garments of untreated cotton. Bare skin protection: Wear dark
substantial clothing, Button collar to protect chest and neck and button
pockets to prevent entry of sparks.
2) Eye and head protection
Protect eyes from exposure to arc. NEVER look at an electric arc without
protection. Welding helmet or shield containing a filter plate shade no. 12 or
densermust beusedwhenwelding.Placeoverface beforestrikingarc.Protect
filterplatewithaclear cover plate. Cracked or broken helmet or shield should
NOT be worn; radiation can pass through to cause burns. Cracked, broken,
orloosefilterplatesmustbereplacedIMMEDIATELY.Replaceclearcoverplate
when broken, pitted, or spattered. WE SUGGEST you wear flash goggles with
side shields under the helmet, to give some protection to the eyes should the
helmet not be lowered over the face before an arc is struck. Looking at an
arc momentarily with unprotected eyes (particularly a high intensity
gas-shielded arc) can cause a retinal burn that may leave a permanent dark
area in the field of vision. Before welding whilst wearing contact lenses, seek
advice from your optician.
3) Protection of nearby personnel
For production welding, a separate room or enclosed bay is best.
In open areas, surround the operation with low reflective, non- combustible
screensorpanels.Allowforfreeair circulation,particularlyatfloor level.Provide
face shields for all persons who will be looking directly at the weld. Others
working in the area should wear flash goggles. Before starting to weld, make
sure that screen or bay doors are closed.