Because persons performing welding wear high-density
glasses or face shields, they cannot see what is going on in lower light levels. They
also may not be able to monitor such a large area. When the welding operation cannot be
confined or performed in a safe location free of combustibles, a fire watcher assists the
welder. The fire watcher’s job is to monitor the area around the operation for lingering
sparks or fire and to extinguish them.