Many manufacturers use one of two options to clear the air of welding fumes – filter the dirty air and recirculate clean air inside the facility, or exhaust the dirty air outside and provide clean replacement air from outside.
The U.S. Chemical Safety Board has long asserted that chemical dust explosions are a "serious industrial safety problem." CSB research reveals that nearly 200 dust fires and explosions have occurred in U.S. industrial facilities over the past 25 years, resulting in approximately 100 fatalities and 600 injuries.
According to OSHA, combustible material can burn rapidly when in a finely divided form. If such a dust is suspended in air in the right concentration, under certain conditions, it can become explosive. Even materials that do not burn in larger pieces can explode in dust form.
A rule to establish standards for combustible dust that’s been in the works since 2009 is scheduled to move closer to completion in 2014, with a proposed draft regulation due this spring.
