A recent question came up regarding the suitability of flame-resistant clothing as protection for welding applications. Although clothing ignition and burn injury is of concern for welders, there are certain aspects of FR fabrics that need to be understood for this specific application.
Are FR garments/fabrics suitable for welding? –
FR fabrics in general, are not designed to eliminate all burn injuries. They are designed to not ignite and continue to burn, and to minimize the wearer’s burn injury when exposed to accidental, momentary ignition sources. This is reinforced by the definition of flame resistance, written in ASTM F2302 (Standard performance Specification for Labeling Protective Clothing as Heat and Flame Resistant): “the property of a material whereby flaming combustion is prevented, terminated, or inhibited following application of a flaming or non-flaming source of ignition, with or without the subsequent removal of the ignition source.” There is nothing in the FR clothing standards that states they will prevent burn injury.
In addition, standard FR clothing is not designed to be used as primary protection in welding applications. There are fabrics specifically designed for welding applications for that reason. The purpose of wearing FR clothing in a welding application is its ability to resists ignition, should it be exposed to accidental sparks or spatter.
Also, the warning label inside many FR clothing items states “Do not use for protection against continuous thermal loads”, which is what you’ll experience if welding sparks or spatter land in such a way as to remain on the garment for an extended period of time or where sparks are projected against the clothing continuously.
In ANSI Z49 the standard for safety in welding processes, it addresses protective clothing. In section 4.3 it states “clothing shall be selected to minimize the potential for ignition, burning, trapping hot sparks, or electric shock.” It goes on to state “Clothing shall be made of suitable materials, to minimize skin burns caused by sparks, spatter, or radiation.” In section 4.3.3 it also states “durable flame-resistant aprons shall be used to protect the front of the body when additional protection against sparks and radiant energy is needed. As you can see, the American National Standard for welding processes also talks in terms of minimizing not preventing skin burns.
Because garment manufacturers are not able to know every application in which their clothing will be used, warning label typically state “The user is responsible to determine that this garment is appropriate for the intended use.” Typical FR garments can play an important role in welding applications but as I stated earlier, they are not the primary protection for the wearer. In certain situations the wearer can sustain some localized burns, the garments will likely exhibit burn marks and holes, but they should not ignite and burn, which is what they are designed to do. There are FR fabrics designed for welding and will hold up better than other FR fabrics. However, in addition to FR garments, welders should use welding aprons, sleeves and leggings as these products are specifically designed for welding applications.