One of the best ways of securing buildings that house potentially combustible equipment such as dryers and dust collectors is to provide safeguards for these through either explosion vents or suppression systems. Vents release the pressure from an explosion outside of the equipment, whereas suppression systems use suppressants such as chemicals to extinguish the fire.
The question is which should you choose for your vacuum conveyor? Vents as a whole are cheaper to install but are not suitable for all installations, making a suppression system the preferred choice. Let’s look at some examples of when a suppression system is better.
K is the pressure created in an explosion. The higher the K the larger the vent needs to be, which in turn increases the overall cost. A suppression system is not affected by the value of K meaning if the value is high, it might be the less expensive option.
Space is limited
When there isn’t enough space to accommodate large vents for one reason or another, then a suppression system is the logical choice as it takes up minimal space.
Material is hazardous
If the material is moved through a vacuum conveyor and is in any way toxic or biologically active so it cannot be released into the atmosphere, explosion suppression is obviously the only choice.
There isn’t enough space to vent
By estimating the size of any possible explosion caused by the equipment you’ll be able to predict how much space could be affected around the equipment. The NFPA gives equations which allow you to estimate how far the flames of an explosion are likely to extend given the size of the equipment involved. One example shows that Vacuum Conveyors of 10 cubic metres can throw a flame for up to 17 metres out of a vent. If you don’t have 17 metres of space free, then you should opt for a suppression system.
Equipment is situated inside
Explosion vents work by rupturing which releases the pressure from an explosion outside the equipment. In order to protect people and equipment it is necessary that the vents discharge outdoors. As a result, ducting must be used to connect the vents with the outdoors. This ducting can add to overall costs, especially if the vented equipment is far from the building’s exterior walls.