What considerations should be made when selecting welding helmet lens shade?

Modern welding helmets and googles are designed to protect the user’s eyes and face from a number of welding and related hazards.  A welder-fitter may use one helmet to perform grinding, plasma-arc cutting, GTAW (TIG) on thin materials, GMAW (MIG) on thick plate, and air carbon arc-gouging (CAC-A).  These processes emit light energy at infra-red, visible, and ultra-violet wavelengths as well as flying hot sparks and particles. 

In addition to the types of light energy emitted, the intensity of the light energy varies.  Although somewhat process dependent, generally with electric arc processes the intensity of the light increases as the welding current being used increases.

Some arc welding processes may operate at a current of less than 20 amps (e.g., plasma arc), while other open-arc welding or gouging processes may approach 1000 amps.  For this reason, the protective lenses are made to different standard shade levels up to the darkest shade of #14. Please be aware that the welding arc produces a full spectrum of ultra-violet ray light (A, B & C) in varying intensities as noted above, so consideration must be given to ensure all parts of the body are protected from the effects of UV rays.

So where should you look for solid recommendations on what shade level to use for a particular application? 

I recommend that everyone look to Canada’s national standard for “Safety in Welding, Cutting, and Allied Processes”, CSA-W117.2-19.  Table 7 in the latest edition provides detailed guidance on lens selection, along with all the critical aspects concerning welding safety.

This standard has been developed since the mid-1970’s (first published 1974) by a dedicated group of volunteer industry professionals from across Canada who make up the CSA-W117.2 Technical Committee.  This standard is now in its 7^th (2019) edition, but the biggest news is that it has recently been made freely accessible electronically to anyone in Canada through the Canadian Standards Association’s website https://www.csagroup.org/store/product/CSA%20W117.2%3A19/ . An article in the 2021 Fall edition of WELD will walk you through this process.

There are too many injuries, accidents, and fires in Canada where welding and related activities are at the root of the event.  We urge anyone with questions about welding safety to proactively look to CSA-W117.2 for direction. 

Dave Hisey, chair of the T/C for CSA W117.2; chair of CSA C232 (CSC26) Electric Welding Equipment. He also represents Canada on Commission VIII Welding Health and Safety with the International Institute of Welding. A volunteer, Dave, is sponsored in this work by the CWB Group. Please contact him via email drhisey@shaw.ca with your comments or if membership on CSA W117.2 or CSA C232 technical committees is desired.