Dry Chemical Suppression Systems

Posted by Lee Kaiser on Dec 12, 2017 9:51:55 AM

Often found in a variety of industrial settings, dry chemical systems provide flexibility based on the size and configuration of the application. These systems are less-expensive and very effective at extinguishing fires, but are also very messy to cleanup. In this video, ORR VP of Engineering Lee Kaiser discusses dry chemical suppression systems, how they work, their characteristics, and the applications they're often used for. 



Dry Chemical Suppression SYSTEMS

Lee: "Let's dive into our first system, and we'll do that by talking about dry chemical suppression systems. Dry chemical systems discharge powders into a space to extinguish a fire. You can have different types of powders.

Sodium bicarbonate for a Class B and some Class C fires, that's baking soda, right? Sodium bicarb, as we sometimes call it, but it's basically baking soda. In a dry chem system using sodium bicarbonate we'll have a big tank, like one of these red tanks here, and off to the side there'll be a high-pressure nitrogen cylinder. That tank will be filled with a dry powder, then when we actuate the system we'll open up that nitrogen tank, and it will discharge pressure into the dry powder. This will then push it out into the piping and to the nozzles to extinguish the fire, wherever that's at.

We have some other powders that we can use, monoammonium phosphate for ABC fires. That's really common in ABC dry powder extinguishers. I'm sure hanging in this hotel close to us there's a Class ABC extinguisher using that dry powder in it.

Characteristics of Dry Chemical Systems

Some of the characteristics of dry chem system: very fast extinguishment. Dry chem systems are sort of old, feels like they're old, but they work really well. We don't think about them a lot. Typically that'll be the fastest extinguishing system that we'll talk about this morning. We can extinguish fires typically in less than 20 seconds after discharge with dry chem. It works very well.

These two things here, economical and extensive discharge cleanup. Here's my nickname for dry chem, Cheap and dirty. Pretty economical to install, but the powder makes a mess, so you have to apply dry chem systems where it makes sense. Can you tolerate all the cleanup? Could you tolerate the contamination of whatever you're doing in that space from the dry powder?

Another advantage of dry chem systems: typically it's one of the only systems that we can use outdoors. This is because the powder has mass and it can get to whatever's burning when there's a given wind happening in that outdoor-type application.

Uses and APPLICATIONS of Dry Chemical Systems

Designs can be both pre-engineered and engineered. Some of the uses: we use them in total flood systems. We can use them in local application. Now, dry chem systems are really tolerable of uncloseable openings.

Some of the applications: paint systems. We see a lot of dry chem systems going for paint booths inside of light manufacturing facilities where you need to paint something. You buy a pre-fab paint booth, install it in your building. The fire marshal walks in and says, "Hey, that needs fire suppression," and so your choices typically are adding sprinklers to your building, and if you don't have sprinklers that's a problem, so therefore your option is usually a dry chem system. Those can be put in, again, cheap and dirty, for your paint booth.

We see them for hazardous storage rooms. Anytime we want to store flammables inside of a building, or like this instance here. This picture is a little prefabricated skid-mounted hazardous materials or flammable storage shed, and this red box is a little pre-engineered total flood dry chem system, so when a fire happens in here, it just discharges and puts the fire out."

Topics: Suppression, Nationwide

Featured Download

Subscribe to the Fire Protection Blog