How to Prevent Dust Explosions
The FIBC, or Flexible Intermediate Bulk Container, commonly known as a bulk bag, is a highly effective method of packing, storing and transporting goods, including food and agricultural products, chemicals, building materials and so on, in dry, granular, powder, flake or dust form. However, there is an important hazard to be aware of when it comes to bulk bags, which is the threat of electrostatic ignitions, or dust explosions.
Dust explosions can not only result in significant loss of product but can be dangerous to workers and equipment. Bulk bag users need to be aware when handling hazardous ingredients in bulk bags that this is a danger, and they should know how to choose bulk bags to reduce the possibility of such events.
How Do Dust Explosions Happen?
Dust explosions happen when electrostatic discharges trigger the volatile material in the bulk bag. This usually takes place when you fill or empty the bag, as this is when the most agitation of the material against the bag takes place. Electrostatic charge can build up and discharge when brushing against the surface of an insulating FIBC or liner. These discharges can ignite flammable gas, vapor and dust atmospheres. Spark discharges can also occur from conductive parts of bags that need to be grounded if they are not grounded.
Avoiding Dust Explosions With Bulk Bags
To avoid dust explosions, it’s important to know the characteristics of the goods you store in your FIBC before you select your bulk bag. Have the following information available to you:
- Is the material you pack combustible? If your product has no explosive or flammable characteristics, you do not have to worry about dust explosions. However, it’s worth noting that the majority of powder materials in general industries are made up of combustible dust.
- Are flammable gases or vapors present wherever you are packing or storing your goods? Take the time to evaluate whether or not there may be flammable gases present in your factory or warehouse. Some packaged materials may actually release off-gases into the atmosphere over time.
- What is the Minimum Ignition Energy (MIE) of the dust material? The MIE is the lowest level of electrostatic spark energy that could ignite a dust cloud. You can have your material tested to find out the MIE if the information is not readily available. If the MIE is below 25 megajoules, there is a significant combustion risk, and you should also find out the Electrostatic Chargeability and Volume Resistivity and Charge Relaxation Time characteristics for your materials.
Choosing Your Bulk Bags
You have four types of FIBCs to choose from, and which ones you pick will be in part dependent upon your material’s electrostatic discharge and combustion risk. If you have conductive powders or material with a volume resistivity below 1060 hm.m, you will need to use Type C groundable bags. However, if you use these types of bags, make sure that they are grounded, as ungrounded Type C bags have a greater risk of explosion than Type A or Type B bags.
Whether or not Type D bulk bags are appropriate will depend on the situation. These bags can protect the substance within the bag but generate a localized electrostatic field that could polarize conductive objects in their vicinity.
Inside Liners in Bulk Bags
You may use or be interested in using inside liners for your bulk bags to avoid leakage or to further protect your goods. You should be aware liners can actually increase the chances of electrostatic discharge and dust explosion, so if you are packaging potentially combustible material, you should consult with your bulk bag manufacturer about the use of bulk bag liners and the type of liner it is most appropriate and safe to use for your packaging situation.
Need Help Choosing the Safest Bulk Bags for Your Operation?
If you’re not sure if your products present a high dust explosion risk and you need help determining which types of bulk bags are right for you to protect your inventory and your workers from such dangers, Midwestern Bag & Supply can help. Call us at 515-393-2947 for completely free bag diagnostics.
Our experts will assess all your bulk bag needs based on the material you want to package and your goals for utilizing our bags, and help you design bags ideally suited for your particular enterprise. You can also contact us online right now to learn more.