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The Importance of Safe Dust Collection

August 9, 2012

Safely operating dust collection systems has become increasingly complicated over the last decade. New regulations from OSHA and the NFPA have sought to improve the safety of collecting combustible and explosive dusts. For OSHA, this topic has even been identified as a National Point of Interest. Unfortunately, dust-related explosions have become somewhat of a regular occurrence in the news (think Foxconn and Imperial Sugar). However, despite the regulatory efforts and recent publicity the issue has received, it is still surprising how some manufacturers choose to approach safely controlling and collecting dust that results from manufacturing processes at their facilities.
    The reasons manufacturers cite for not addressing this issue vary widely. Most companies hesitate because of the cost associated with the additional measures that may be required to be fully compliant. While the costs are definitely obstacles given that the safety options or installation adjustments required can in some cases exceed the cost of the dust collector itself, not properly addressing these concerns results in partially protected workers and facilities. Other companies cite general confusion regarding what is required to achieve compliance. This is understandable due to regulations that have undergone revisions, shifts from guidelines to standards, inconsistency between standards, lack of trained inspectors to review compliance and lack of knowledgeable staff on individual companies’ payrolls. So, in the face of these challenges, how can manufacturers successfully approach dust collector system safety to arrive at the right solution?
    Designing and operating a safe and effective dust collection system begins with a complete and comprehensive analysis of your dust that identifies the general characteristics as well as the associated hazards. Establishing basic information such as the bulk density (specific gravity), terminal velocity, particle size distribution, and moisture content will allow the collection system to be properly sized. Part of this analysis should also include determining whether the dust is combustible or explosive in accordance with current NFPA standards. This is one of the most commonly overlooked steps because of the associated up-front cost. However, avoiding this step or using incorrect information can have dangerous consequences. Also, it’s important to take the time to review the MSDS sheets (if available) for other potential hazards and guidance on how to handle the collected material.
    A fully operational dust collection system is comprised of the hood or capture device, the ducting system, the dust collector and the air moving device. If any one of these components is not designed with the dust characteristics and hazards in mind, the entire system safety is in jeopardy. Manufacturers often believe that simply having a dust collector equipped with an explosion vent is adequate protection but they ignore the important considerations of the complete system. For example, poorly designed ducting that does not maintain proper conveyance velocity during operation creates performance and safety hazards where dust build-up can result in fire hazards or even structural failure.
    Systems must also be properly maintained in order to achieve the desired level of consistent performance and safety. Filter changes, removing dust build-up on hoods, pressure gauge accuracy, airflow validation and non-obstructed explosion vents are just a few of the items which should be regularly checked to help ensure ongoing safe operation. In addition, operational and maintenance staff should be sufficiently trained and have a solid understanding regarding what the target system performance is, how to verify this performance and how to service the equipment when necessary.
    Investments in dust collection systems are intended to provide protection to your company’s most valuable assets - your workers and your facility. Dealing with combustible and explosive dust hazards come with associated additional costs but the risks of not adequately addressing the issue are much greater. The amount of publically available information available combined with the documented examples of property damage and loss of life from dust explosions should compel manufacturers to take the necessary steps to ensure that their dust collection systems are safe. And, dust collector manufacturers, such as United Air Specialists, are willing and eager to help with the education process so be sure to tap into their expertise and knowledge regarding dust collection system safety when you are considering vendors to meet your specific dust collection needs.
    Travis Haynam is director of business development, United Air Specialists Inc. (Cincinnati, OH). For more information, visit www.uasinc.com or call 800-252-4647.
 

United Air Specialists Inc.