Like all PPE, weld viewing system components may appear to be alike but there are significant differences in material, workmanship and performance. Moreover, there are many viewing system products that are mislabeled and are not at all what they are claimed to be.
While there are numerous weld viewing system component suppliers, there are very few full system suppliers that can provide a full package. Perhaps the best system available today is the Fibre-Metal brand by Honeywell. Every component in the Fibre-Metal passive protective weld viewing system is unique, top quality, and works together as a system with precision not available in other brands.
The Fibre-Metal brand system begins with their top quality welding helmets made from unique materials in exclusive designs. Their attention to detail in both their front loading stationary and lift-front viewing system holders sets them apart from the others.
The Fibre-Metal by Honeywell brand uses the brand name "High Performance" for their passive weld viewing system components. The illustration above shows the proper component "stack" for a lift-front helmet model. The stack begins with a HIGH PERFORMANCE model CR.39 cover plate. The cover plate performs the very important task of protecting the more expensive filter plate. It must be able to withstand welding sparks and spatter, physical abuse like scratches and abrasions and the contaminants of a welding environment. CR. 39 is the material best suited for those tasks. Other materials, like cheap "all plastics", simply don't hold up. And polycarbonate, while a great impact resistant material for a safety plate, is adversely affected by many substances related to welding and should not be used for a cover plate.
While many cover plate brands are labeled "CR. 39", they vary in terms of the amount of the actual CR. 39 material contained in the product. The Fibre-Metal by Honeywell HIGH PERFORMANCE CR. 39 cover plates contain the highest actual percentage of CR. 39 material of any brand which makes them the top performers with the longest service life.
Next in the stack is the actual passive filter plate. The HIGH PERFORMANCE gold plated filter lenses from Fibre-Metal reflect harmful radiation rather than absorbing it. The high quality gold coating also reflects heat which helps keep a welder cooler and more comfortable. There are other brands of gold coated filter plates but only the HIGH PERFORMANCE brand allows a welder to see his work in pure natural color. A more comfortable, better protected welder with a better view of his work will stay on the job longer and produce more with fewer rejects. An abrasion resistant coating and a unique picture frame buffer are additional quality touches.
If a degree of magnification is required, the Fibre-Metal by Honeywell HIGH PERFORMANCE protective viewing system includes one piece, injection molded magnifiers in a wide range of diopters. The optically correct magnifiers provide the ability to view a magnified work area from a normal 12" welding position. Most lesser brands require a welder to move to within 6" of his work to achieve the magnification. The magnifiers are hard coated to reduce scratching for a longer service life.
The last component of the system is the HIGH PERFORMANCE safety plate. Injection molded, optically correct, lightweight, impact resistant polycarbonate safety plates provide an extra margin of protection. The safety plate is the last line of protection in the welding helmet from flying objects. Of course, protective spectacles are the primary eye protection and should be worn at all times under a welding helmet.
Because all components of the Fibre-Metal by Honeywell HIGH PERFORMANCE weld viewing system are either cast (CR. 39) or injection molded, the optical correctness and optical quality are far superior to products that are cut or stamped from sheets. The optical flaws in lesser products can cause eye irritation, headaches and fatigue.
The reason polycarbonate should be used in a safety plate but not a cover plate is positioning in the stack. The cover plate is the most exposed component to the welding elements while the safety plate is the most protected. The cover plate, filter plate and welding helmet shell all shield the safety plate from the things that can adversely affect it.
Once again, it pays to look beyond the surface, dig a little deeper and get past the "they are all alike" mind set when considering the passive weld viewing package you use or provide your workforce. Think of it as a "system" that should consist of the best components designed together to work together. Upgrading can result in fewer injuries, improved productivity and increased profitability.