Flexible Welding Protection
Welding in today's plant environment calls for protection by flexible curtains and portable screens while permitting flexibility in workspace design.
WELDING is dangerous enough when it takes place in an enclosed welding shop with the combination of heat, burning metal, and the optical rays given off by the process. On an open manufacturing floor or maintenance shop, the welding risks to those who are nearby and unprotected include:
- Exposure to ultraviolet radiation (UV). UV is created by the electric arc in the welding process. If the skin is exposed to UV, it can result in severe burns. In addition, UV exposure can damage the lens of the eye, which can lead to what is called "arc-eye." Arc-eye is a condition in which it feels as though there is sand in the eye.
According to the Bureau of Labor Statistics, nearly 2 million workers are engaged in welding. Of that number, about 365,000 annually--breaking down to 1,400 a day--fall victim to some type of eye injury.
- Exposure to infrared radiation (IR). IR is also created by the electric arc, as well as other cutting equipment. IR can heat the surface of the skin, as well as the tissues just below the skin. This can lead to thermal burns.
- Exposure to intense visible light. Various injuries can result if the eye is exposed to intense visible light, including adaptation, pupillary reflex, and shading of the eyes. In particular, retinal damage can be sustained during arc welding.
Surrounding those welders are hundreds of thousands of other workers. The reason is in almost all plants, management is trying to get to the most return on investment out of the facility. Providing extra room between operations such as welding and assembly is a luxury no manufacturer can afford, not to mention that in spreading out activities, material handling efficiency suffers. Workers in a heavy equipment manufacturing plant typically can find themselves working just within a few feet of the welding operation.
At least the welder can think ahead and don gloves, visors, goggles, and protective clothing. For those nearby going about other business, taking those precautions would be impractical.
Providing a solid wall barrier is costly, or in the cases of many of these operations, impossible. Plants have attempted makeshift means to protect their workers, erecting wood or metal partitions or hanging opaque canvas from the ceiling and crossbeams.
None of these solutions really fits with a professional manufacturing or maintenance operation. The partitions are unwieldy to handle, can have seams between their sections that enable light to escape, can box in the welding fumes, block out light, impede the work, are difficult to enter and exit, and cannot provide outsiders (particularly supervisors) an idea of how work is progressing. For an operation that periodically brings customers through, these setups look just plain ugly.
Flexible welding enclosures provided by heavy-duty vinyl curtains and portable welding screens can provide fast setup, protection, and flexibility. Both feature transparent panels typically made from polyvinyl chloride plastic combined with a color dye, flame-retardant chemicals, and a compound to absorb ultraviolet rays. The panels confine weld splatter and prevent fumes from migrating into other working areas. Those working close by do not have to worry about degrading their vision when they glance over to the welder. This includes the supervisors, who can keep an eye on the progress of work without losing their eyesight.
Bear in mind, however, that no transparent welding panel can substitute for proper eye protection when directly viewing welding arcs at close range.
The transparent panels also add to safety when material handlers have to bring work and equipment in and out of the welding area. As the vehicles enter and leave the enclosed section, drivers have a view ahead to be sure pedestrians are safely out of the way.
Both curtains and screens are ideal for flexible manufacturing in which the floor plan and the work layout are constantly changing. Welding screens can be easily set up where needed and provide protection when on-site maintenance welding is performed or for small production setups.
Weld curtains enclose larger manufacturing and maintenance operations and can encompass an entire welding department. The length of a single side of a curtain wall can be limitless, and track layout enables the enclosure to conform tightly to the needed welding floor space.
To facilitate material handling, weld curtains hang from the ceiling with easily attached and reattached tracks. The hanger hardware has rollers that glide along a ceiling track. The gap between the ceiling and the top of the curtain enables the installation of exhaust blowers to pull welding fumes out of the area.
When large machinery has to be brought in and out of the area or a forklift needs to enter the area, the curtains effortlessly slide out of the way. In accordance with the lean manufacturing concept, the curtains can configure welding cells to meet the needs of the operation and any change to make it more efficient.
Flexible Enclosure Basics
As for the basics of flexible welding enclosure selection:
For curtains and screens
- Vinyl should be at least 14 mil thick to withstand weld splatter, as well as being able to withstand rugged manufacturing/maintenance environments. The thickness of the curtain also means it can hold its own weight when being suspended from the ceiling or on the weld screen frame to prevent the panel from tearing.
- Panels should block harmful UV rays.
- They should have the capability to contain welding fumes.
- The panel material must be capable of passing the strictest state fire retardancy tests.
- The panel material must be mildew and rot resistant.
For welding curtains
- Though some manufacturers offer floor-to-ceiling transparent panels, other designs are available that have an opaque vinyl section at the top and bottom panel, having the transparent section running along the middle of the panel. This design provides greater panel strength and longer life.
- The suspension hardware must allow easy opening of the curtains. In a typically busy operation, people and vehicles will pass in and out of the area scores of times during the day. Though easy access is important, still more is easy closing to encourage people to shut the gap between the curtains when passing in and out of the area. The opaque material on the bottom and top should be chain weighted, and both the top and bottom opaque vinyl should be rot and mildew resistant. The center transparent panel could be attached with hook-and-loop material. This allows portions of the panel to be changed without replacing out a whole new curtain panel.
- The curtain panels can be interlocking hook-and-loop material to prevent personnel who do not belong in the area from entering.
For welding screens
- Panels and frames should be easy to move to encourage their use and discourage welders from avoiding the use of the screens when the job is regarded as brief.
- Make sure the screen frame is not flimsy. To minimize danger, the one time a screen should not topple over is during welding.
- Screens should have the capability to hinge together quickly for setups of various configurations.
- Corner panels to block light from exiting are important.
Because the idea here is to have transparent protection, the panels need to be wiped down periodically to remove dirt and fumes. The plastic can create a static charge, and so it will attract debris. Burn holes do occur in the panels; it's a good idea to keep a patching kit handy.
Among the operations involved with production and maintenance, welding is the one activity performed by so many that offers one of the greatest hazard levels, no matter which industry is using it. With plants becoming more cramped, this risk now gets transferred from those doing the work to those working nearby. Welding curtains and screens provide the opportunity for welders to work safely side by side with other processes.
This article appeared in the September 2006 issue of Occupational Health & Safety.
This article originally appeared in the September 2006 issue of Occupational Health & Safety.