Because the role of industrial dust collectors is so crucial to manufacturing and industrial environments, possibilities of a dust collector fire are met with serious concern in manufacturing facilities. Without preventive measures in place, the potential for a dust collector fire is very real. A simple spark can result in a combustible dust fire that could race through a facility with explosive force. Preventing such fires is critical for worker and plant safety. Prevention starts with recognizing common causes and ongoing preventative maintenance.
Industrial dust collectors capture valuable products, as well as provide a healthy work environment for employees, and also to ensure that manufacturers comply with local, state, and federal regulatory codes and laws. For air quality control inside and out, proper ventilation and air circulation of dust and fumes in many processing plants and manufacturing facilities are controlled by dust collectors. However, the very nature of dust collectors provides ample fuel for a combustible fire.
For any fire to occur, it requires three components—oxygen, heat, and a fuel source. As a dust collector provides an airflow that pulls dust and fumes from the air to be filtered, which may be circulated back into the plant, it provides two of the three components needed to start a fire—a fuel source and oxygen. More than being aware of the possibility of a combustible dust fire, proper operation of a dust collector includes limiting the opportunity for a fire to occur. Prevention begins with identifying causes and implementing preventive measures.
Here are 5 tips to help in preventing and lowering the potential of a dust collector fire from happening at your facility:
Identify & Eliminate Ignition Sources
- Combustible fires can occur when an ignition source such as an airborne ember or spark enters the dust collector and ignites. Thus, identifying and eliminating any possible ignition source around the dust collector should be prioritized. In manufacturing facilities where metal cutting, grinding, welding, and like processes occur, the work should be carried away from the dust collector. If a spark from the grinder or an ember from welding strikes the dust collector’s filter media, it could result in combustion and a serious fire throughout the facility. Though it goes without saying, no smoking around the dust collector should be strictly enforced. All dust collection systems build up static electricity. If these systems are not grounded, electricity becomes a hazard that could start a fire. Ensure a proper grounding kit is in place while keeping in mind a large system may need more than one kit. This safety accessory is essential to any complete dust collection assortment.
Provide Deflagration Vents for Protection
- If a dust collector is processing combustible dust, equip the collector with deflagration vents. Deflagration vents are a cost-effective passive method that can redirect the force and path of the fire away from the work environment. The vents are designed to open when predetermined pressure levels are reached within the dust collector. If there is combustion, the vent allows passage of the initial wave of flame and excessive pressure, directing it to a safe area, reducing and limiting danger, hazards and damage.
Clean Dust Hoppers
- Remember that a dust hopper is not a storage bin for the product and dust collected from the plant or facility. The hopper is an important part of dust collection, but it is not the endpoint. Allowing a hopper to fill and accumulate too much dust provides ample fuel and risk for combustion. An overflowing hopper can also clog a system, greatly reducing a dust collector’s effectiveness. Hoppers need to be monitored continuously or install self-dumping hoppers for easy dust disposal.
Change Filters Regularly
- Another simple preventive maintenance method to reduce fire risk is by changing the filter media when required. Filters should be changed at manufacturer-suggested intervals. That may be when airflow through the dust collector system reaches a differential pressure limit or when there is a noticeable pressure drop that negatively affects the capability of the dust collector to capture the dust or fumes within the facility. As an added preventative measure, even long-life cartridge filters should be monitored at regular intervals. In plants and facilities with processes releasing heavy dust loads, frequent filter replacement is recommended.
Protect the Ductwork with Isolation Valves
- Protecting ductwork can help contain a dust collector fire from spreading. As a preventive measure, if combustion occurs, having flow-activated isolation valves installed within the ductwork protects work areas from the release of smoke and fire into work environments. Such protection for the ductwork is recommended in the National Fire Protection Association (NFPA) guidelines. When a deflagration pressure wave occurs within a dust collector, a properly designed flow-activated isolation valve closes to prevent further flame and smoke.
While these are the 5 most common methods to protect a baghouse from fire, there are additional methods, including chemical isolation. Chemical suppression systems are designed to detect an explosion hazard in milliseconds and then release a chemical agent to extinguish the flame before an explosion can occur.
If you’re interested in learning more about our baghouse products, parts or services, contact us today. At CPEF, Inc., we will engineer, manufacture, install and service your optimum collection system.