Safety
Mishaps frequently occur in
welding operations. In many instances, they result in serious injury to the welder or
other personnel working in the immediate area. In most cases, mishaps occur because of
carelessness, lack of knowledge, and the misuse of available equipment. Precautions that
apply to specific welding equipment are pointed out in the chapters that cover that
equipment. In this section we are particularly interested in such topics as protective
clothing, eye protection devices, and practices applicable to the personal safety of the
operator and personnel working nearby.
Proper eye protection is of
the utmost importance. This covers the welding operator and the other personnel, such as
helpers, chippers, or inspectors, who are in the vicinity of the welding and cutting
operations. Eye protection is necessary because of the hazards posed by stray flashes,
reflected glare, flying sparks, and globules of molten metal. Devices used for eye
protection include helmets and goggles. Figure 3-56 shows several types of eye protection
devices in common use.
NOTE
In
addition to providing eye protection, helmets also provide a shield against flying metal
and ultraviolet rays for the entire face and neck.
Flash goggles (view A)
are worn under the welder’s helmet and by persons working around the area where
welding operations are taking place. This spectacle type of goggles has side shields and
may have either an adjustable or nonadjustable nose bridge.
Eyecup or cover type
of goggles (view B) are for use in fuel-gas welding or cutting operations. They are
contoured to fit the configuration of the face. These goggles must be fitted with a shade
of filter lens that is suitable for the type of work being done.
NOTE
The
eyecup or cover type of goggles are NOT to be used as a substitute for an arc-welding
helmet.
For electric arc-welding and
arc-cutting operations, a helmet having a suitable filter lens is necessary. The helmet
shown in view C has an opening, called a window, for a flip-up filter lens 2 inches by 4
1/4 inches second is to eliminate the harmful infrared and ultravio-in size. The helmet
shown in view D has a 4 1/2-inch by 5 1/4-inch window. The larger window affords the
welder a wider view and is especially useful when the welder is working in a confined
place where head and body movement is restricted. When welding in locations where other
welders are working, the welder should wear flash goggles beneath his helmet to provide
protection from the flashes caused by the other welders’ arcs. The flash goggles will
also serve as eye protection when chipping the slag from a previous weld deposit.
Helmets and welding goggles
used for eye protec-tion are made from a nonflammable insulating material. They are fitted
with a removable protective colored filter and a clear cover lens.
NOTE
The
purpose of the clear cover lens is to protect the filter lens against pitting caused by
sparks and hot metal spatter. The clear lens must be placed on the outside of the filter
lens. The clear lens should be replaced when it impairs vision.
Filter lenses are
furnished in a variety of shades, which are designated by number. The lower the number,
the lighter the shade; the higher the number, the darker the shade. Table 3-1 shows you
the recommended filter lens shade for various welding operations. The filter lens shade
number selected depends on the type of work and somewhat on the preference of the user.
Remember, a filter lens serves two purposes. The first is to diminish the intensity of the
visible light to a point where there is no glare and the welding area can be clearly seen.
The let radiations coming from the arc or flame; conse-quently, the filter lens shade
number you select must not vary more than two shades from the numbers recom-mended in table 3-1.
Rule of thumb: When selecting
the proper shade of filter lens for electric-arc welding helmets, place the lens in the
helmet and look through the lens as if you were welding. Look at an exposed bare light
bulb and see if you can distinguish its outline. If you can, then use the next darker
shade lens. Repeat the test again. When you no longer see the outline of the bulb, then
the lens is of the proper shade. Remember that this test should be performed in the same
lighting conditions as the welding operation is to be performed. Welding in a shop may
require a shade lighter lens than if the same job were being performed in bright daylight.
For field operations, this test may be performed by looking at a bright reflec-tive
object.
WARNING
Never
look at the welding arc without proper eye protection. Looking at the arc with the naked
eye could lead to permanent eye damage. If you receive flash burns, they should be treated
by medical personnel.
A variety of special
welder’s clothing is used to protect parts of the body. The clothing selected varies
with the size, location, and nature of the work to be performed. During any welding or
cutting operation, you should always wear flameproof gauntlets. (See fig. 3-57.) For gas
welding and cutting, five-finger gloves like those shown in view A should be used. For
electric-arc welding, use the two-finger gloves (or mitts) shown in view B.
Both types of gloves protect
the hands from heat and metal spatter. The two-finger gloves have an advantage over the
five-finger gloves in that they reduce the danger of weld spatter and sparks lodging
between the fingers. They also reduce finger chafing which sometimes occurs when
five-finger gloves are worn for electric-arc welding.
Many light-gas welding and
brazing jobs require no special protective clothing other than gloves and goggles. Even
here, it is essential that you wear your work clothes properly. Sparks are very likely to
lodge in rolled-up sleeves, pockets of clothing, or cuffs of trou-sers or overalls.
Sleeves should be rolled down and the cuffs buttoned. The shirt collar, also, should be
fully buttoned. Trousers should not be cuffed on the outside, and pockets not protected by
button-down flaps should be eliminated from the front of overalls and aprons. All other
clothing must be free of oil and grease. Wear high top-safety shoes; low-cut shoes are a
hazard because sparks and molten metal could lodge in them, especially when you are
sitting down.
Medium- and
heavy-gas welding, all-electric weld-ing, and welding in the vertical or overhead welding
position require special flameproof clothing made of leather or other suitable material.
This clothing is designed to protect you against radiated heat, splashes of hot metal, or
sparks. This clothing consists of aprons, sleeves, combination sleeves and bib, jackets,
and overalls. They afford a choice of protection depending upon the specific nature of the
particular welding or cutting job. Sleeves provide satisfactory protection for welding
operations at floor or bench level.
The cape and sleeves are
particularly suited for overhead welding, because it protects the back of the neck, top of
the shoulders, and the upperpart of the back and chest. Use of the bib, in combination
with the cape and sleeves, gives added protection to the chest and abdomen. The jacket
should be worn when there is a need for complete all-around protection to the upperpart of
the body. This is especially true when several welders are working in close proximity to
one another. Aprons and overalls provide protection to the legs and are suited for welding
operations on the floor. Figure 3-58 shows some of the protective clothing available to
welders.
To prevent head burns during
overhead welding operations, you should wear leather or flameproof caps under the helmet.
Earplugs also should be worn to keep sparks or splatter from entering and burning the
ears. Where the welder is exposed to falling or sharp objects, combination welding
helmet/hard hats should be used. For very heavy work, fire-resistant leggings or high
boots should be worn. Shoes or boots having exposed nailheads or rivets should NOT be
worn. Oilskins or plastic clothing must NOT be worn in any welding operation.
NOTE
If
leather protective clothing is not avail-able, then woolen clothing is preferable to
cotton.
Woolen clothing is not as
flammable as cotton and helps protect the operator from the changes in temperature caused
by welding. Cotton clothing, if used, should be chemically treated to reduce its
flammability. |
