Sometimes it’s necessary to cut or weld, or hot work in the vicinity of your dust collector. However, this can be extremely dangerous if your dust is explosive. A dust collector, after all, is an accumulation of dust. If that material is combustible, careless hot work could lead to a catastrophic explosion.
“Hot work” is defined by OSHA as “welding, brazing, cutting, soldering, thawing pipes, using heat guns, torch applied roofing and chipping operations, or the use of spark-producing power tools, such as drilling or grinding”. Most of us would think twice about welding or cutting in near a dust collector or any other combustible dust. But some tools, even ones that shouldn’t produce sparks, may have faulty wiring. This can lead to a fire or explosion.
Hot Work Procedures
No hot work should be done near the dust collector without the correct procedures (see NFPA 51B). This NFPA standard specifically defines the procedures for conducting this type of work anywhere that it might cause an explosion.
Hot work near or on a dust collector might include repairs or adding/removing a piece of equipment or ductwork. It may include any number of other projects. Before doing this kind of work around the dust collector, you must have a hot work procedure IN WRITING:
- Shall be in writing and available to anyone conducting hot work in the area
- It must require an inspection of the work area before the work starts
- Must have a permit signed to show that all phases of the work have been inspected and approved
The program should assess safety equipment in the area. On a dust collector that might include a spark arrestor, spark detector, fire suppression or sprinkler system, abort gate, explosion venting, or other types of fire and explosion safety devices.
Hot work may require completely blocking the ductwork to the dust collector, or if the work is on or close to the collector, may require removing the filters, emptying or removing the hoppers, and thoroughly cleaning the entire dirty air side of the dust collector. a strong g recommendation is that a fire suppression system is in place before hot work begins. This will suppress any fire that might start. Further, remove as much of the dust as possible if it is explosively combustible.
Permits Ensure Safety
NFPA 51B specifies that the company safety specialist will issue a permit for work to proceed once achieving an inspection and determination of safety for hot work. It’s the job of this designated safety specialist to inspect the area of hazards. The specialist ensures the removal of all combustible dust. They confirm the isolation of all sparks and heat and establish safety procedures in the event of a fire.
No one should be allowed to perform ANY type of hot work, including the use of spark-producing power tools, in the vicinity of the dust collector without a permit. However, it happens all the time and puts lives at risk if the dust is combustible. Take the time to assess this hazard in your own workplace. If the hazard exists, your safety professional should set up hot work procedures to make sure no one puts themselves or the facility at risk.