This is one of the most important questions you can ask. The answer to this question can require you to invest in expensive protection equipment or not, but that is much better than the loss of thousands of dollars in equipment, production time, and most importantly, employee safety. There are a few ways to answer this question. Some of which are safer than others. The main question you will need to ask yourself, is the dust combustible?

Is My Dust Explosive?

If the material can react with oxygen then there is a chance it can be explosive. However, just because it is combustible, doesn’t mean it is explosive. Generally if a dust is greater than 500 micron in size, it is not explosive. However, what if the dust is smaller than 500 microns?

The safest course is to send your sample into a test facility for a simple Explosibility Screening (Go/ No Go) test. This test will take a small sample and try to ignite it to see if the sample will explode. If it explodes then an explosion severity test should be performed, which provides data on the speed of the explosion (K_st) and strength of the explosion (P_max). This data is very important to designing equipment that will prevent, contain, or divert explosions safely.

Some dust might be generated from material you got from a vendor, and they might have already done explosion testing on the material. You might be able to use this data for the design of your equipment depending on the process. The main thing being, what are you doing with your process? If you are sorting, grinding, drying, etc. the material then you can be changing the explosibility of the dust. If there has been a change, then the material should be tested again or you can assume it to be explosive and use the suitable published data.

The Explosibility of Dust

The explosibility of dust is highly dependent on the material size and humidity. A few examples would be aluminum. Spirals of aluminum from trimming wouldn’t be explosive, but a fine aluminum powder would be. Another example is wood dust. Dry wood dust is very explosive, while wood with a high water content is not.

You should not depend on your history working with the dust, because dust explosions are fickle. You might be working with dust for 20 years and have no issues and then suddenly there is an explosion. Or it might be the 1^st time you work with a dust that an explosion happens. One thing is for sure, if you have had flash fires with the dust, you definitely should have it test for explosibility. A flash fire is a sign that you have an issue with your process and should do further investigation to make sure you won’t have an explosion and to prevent more flash fires.

Dust Hazard Analysis (DHA)

If your dust is explosive, you will then need to have a Dust Hazard Analysis (DHA) done on your process/ building, etc. The DHA reviews your process, operational and maintenance procedures, equipment, etc.   It then provides procedures, equipment changes, etc. to address the issues and provide for a safe process. OSHA will request a copy of your DHA during any inspection. So it is important that you have an answer to the question “Is my dust explosive?” and have something to back up the answer in case you are asked by OSHA, your insurance company, local fire inspector, etc.

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For more dust collection and material handling literature, visit our website’s literature page at  www.dustcollectorhq.com.

To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click here to speak with a member of our engineering team about your application, anytime. 

Need to implement a cyclone dust collector into an already compliant dust collection system? What does it take to keep everything compliant with the new addition?

Not only do NFPA compliance regulations require a DHA (Dust Hazard Analysis) to be done on all systems that might have explosive dust, they also require the DHA to be updated every 5 years and whenever the system changes. 

Simple Changes in Documentation

Changes might involve adding , removing,  or changing equipment or changes in the material going through the system. 

Since a DHA has already been done, the scope of the change is much less.  Using the information in the original DHA, the equipment that is being changed can be analyzed to make sure it complies with NFPA.  This report will then be added to the existing DHA so that a record of change is documented.  Usually the report is considered a mini-DHA or System DHA. 

The mini-DHA or System DHA often can be conducted by a 3^rd party consultant working with the equipment manufacturer.  This usually can be done without a site visit.  Aerodyne offers the Mini-DHA/ System DHA for our cyclone separators.

There is no substitute for an on-site inspection by an experienced expert. Click here to talk to an engineer about your application. 

OSHA is issuing citations and fines to companies with unsafe combustible dust hazards, using their general duty clause and NFPA 652: Standard on the Fundamentals of Combustible Dust as a guideline. Any industrial facility that creates dusts or uses powders was mandated by NFPA 652 to complete a Dust Hazard Analysis by September, 2020 to identify the presence of combustible dusts and establish a plan for eliminating or mitigating potential risks associated with these dusts in their facilities. The DHA is essentially the framework around which NFPA 652 is built, and the starting point for getting a facility into compliance with the standard as a whole.

Dust Hazard Analysis (DHA) Complexity

The complexity of performing a DHA varies with the complexity of the facilities and processes being analyzed.  For instance, a small wood cabinet making shop with a limited number of dust generating machines will present a less daunting task than a large scale manufacturing facility that use powdered raw materials and performs cutting and grinding of its finished product. It should also be noted that performing a DHA should not be viewed as a “one and done” procedure that is completed and forgotten. As new processes or raw materials that have the potential for impacting a facility’s combustible dust profile are introduced in the facility, the DHA needs to be modified to incorporate these changes accordingly.

Dust Hazard Analysis (DHA) Preparation

Preparation for a Dust Hazard Analysis can also be incorporated into a more comprehensive review of a facility’s dust collection system that examines overall system design, efficiency, and safety. Aerodyne Environmental’s Dust Efficiency Clinic offers dust collection system evaluation services that do just that. An Aerodyne dust collection specialist will review a facility’s equipment, installation, controls, and protective devices with an eye toward improving overall system performance, decreasing maintenance costs, prolonging equipment life, and improving safety and regulatory compliance.

Dust Hazard Analysis (DHA) Report

At the end of the system review, a report is generated that summarizes the existing state of the dust collection system and offers targeted suggestions for areas that can be improved. This valuable service offers facility and plant managers outside expertise in boosting the performance and safety of their systems, and is a logical first step in preparation for a DHA.

To learn more about Aerodyne’s Dust Efficiency Clinic consulting services, call Dan Navicky at (440) 543-7400 or tollfree at (800) 358-7546, or email dc@dustcollectorhq.com.

1. Health and safety
   • Dust can cause health issues, even if the material isn’t a carcinogen or sub-micron. Dusty air can cause issues breathing, allergies, etc.  All of this can cause operators to be sick more often or want a new job.  This can cause increased operating expenses and less efficiency as you have to cover for absences or have to train a replacement.   Small local dust collectors can help clean the air around operators.
   • Some dust is explosive, and the regulatory agencies are requiring that you test the dust to make sure it isn’t. Even if they haven’t gotten around to it yet, a fire or explosion will cause property damage and possibly injury to employees.
2. Maintenance – Dust will get into mechanical equipment and cause increased wear on them. This increases the maintenance on the equipment, lower productivity and increase operational expenses.  Installing a local dust collector can minimize the dust getting to the surrounding equipment, thereby extending their life.  While there are many factors that affect when equipment needs maintenance, minimizing dust in the air will definitely help extend the time between maintenance.
3. Recycling of material – Local dust collection can help capture product / raw material dust before it is contaminated by other material. This dust can then be reused or recycled, thereby lowering the cost of your process.  Cyclonic dust collectors are especially good at collecting un-contaminated material since they have no filters to retain dusts and can be cleaned out.
4. Environmental responsibility – Local dust collection will help you keep fugitive dust from escaping the building and into the environment. While rain and wind often deposit dust back on the ground, the more dust escaping will cause the air to be dirtier. This could cause smell or dust clouds that neighbors will dislike.  Beyond being a good direct neighbor, you may just have a goal to be a better inhabitant on the earth.
5. Higher morale – A cleaner, healthier environment will help your employees be happier at work. If they aren’t irritated from dusty air, there is a better chance they will enjoy work better and be more productive.  This will allow you to produce more at a lower cost.  And the company will make more money allowing the employees to get better raises.

To learn more about which dust collector, please contact our experts at 440-543-7400 or through here.