Basics of Clean Agent Systems

Posted by ORR Protection on Mar 22, 2022 12:45:00 PM

Lee Kaiser, covers the basics of clean system agents and how they work in your building.

watch as Lee dives in-depth on what clean agent systems are, as well as how we test and view a system discharge. 

What is a Clean Agent system? 

I think of clean agents as having a mechanical half and electrical half, and so with the electrical half the fire alarm stuff that we just got done talking about, so we're going to see how that applies.  But first off, I want to highlight what a clean agent systems is.  Some of you know names like FM200 system, Sapphire System, Inergen or NOVEC 1230, those are all brand names for clean agent systems. 

You may not know that you have clean agent system in your building, but you do have one.  Clean agent systems are extinguishment systems, they're chemical extinguishment systems that extinguish a fire without using any water.  They're gaseous total flooding systems, flooding a protected room or compartment with gas, floor to ceiling, wall to wall, no matter where the fire is until it goes out.  They work quickly.  They're fast and affective. 

They're fast in two ways.  They extinguish fires usually between 30 and 45 seconds, and then they activate off of smoke detection when the fire is small.  We want to limit the amount of thermal fire damage to the components, or whatever's involved in the fire inside the room. 

They're safe for equipment and personnel, so the clean agents are electrically non-conductive, unlike water, they will not short out electronics or electrical components.  The clean pieces, they leave no residue.  There is no clean up after the discharge and there's a 5-minute exposure limit to people inside the space after the system discharges, but you can't be in the space if it discharges. What we ask people to do is when they hear the pre-discharge warning signal, we'll start to walk calmly and orderly to exit the space before the system discharges. 


Some of the common applications for clean agents are information technology rooms such as data centers, server rooms, telecommunications facilities, control rooms. Control rooms could be an airport control tower, a control room with computers running, a process at an industrial plant, a control room inside of a power plant, and records, storage and archive rooms. Places where we have irreplaceable assets. 

We consider clean agents from fire protection strategy perspective to be asset protection, so it protects the components or assets inside the room, and by default, by putting those fires out, we also get life safety and structural fire protection. If there's no fire, then there's no impact on life safety or structure. 


Some of the system components that we need to understand before we can go into inspection testing maintenance are the agent storage containers.  The agent or the gas contained inside of a steel cylinder, or storage container.  There's the piping that leads away from it to nozzles that distribute the agent inside of the space.  There's the releasing device that connects to the valve that's on the top of the tank, and then there's the releasing fire alarm systems. 

This is a system listed to release an electrical control head or other type of device and all the other fire alarm system components.  Here's the FM200 cylinder, a cylinder with agent inside of it. The valve is normally closed until we send a signal to an electric control head, which will mechanically open up that valve connected to the fire suppression panel, and the agent goes out through piping to the nozzle. 

On the right, we've got two cylinders this time, connected with flexible hoses to the piping network in red, going to the nozzle, and then we have in blue, we have smoke detectors connected to the blue releasing fire alarm panel. Then the line between the releasing fire alarm panel and the cylinders releasing circuit which would electrically send a signal to open those valves up through releasing devices. 


I want to give you this opportunity to kind of understand what the system does when it senses a fire in the room.  We're going to discharge gas out through the ceiling, and before the gas goes off. We'll hear a little beeping in the background, and then the pre-discharge warning signal that's warning the people and the occupants of the room there's going to discharge.  Then the gas will come out of nozzles in the ceiling, and the vision in the room will be obscured at that point.  We call that fogging due to the agent expanding in the room.  That fogging stops pretty quickly after the system stops discharging, and it returns back to normal vision inside of the room.  A couple of other things that we'll notice is while those nozzles are going off, it's pretty loud. Then here finally we'd also see this a piece of paper taped to the front of that cabinet.  It will be flopping around because we'll know that now the discharge is turbulent because of the gas escaping from the nozzles. 

Back in the day with Halon systems, we used to discharge test those all the time.  Today we use other operational tests to make sure that the system will work, but we don't discharge test systems.  We just happen to have this video of a discharge test happening so it's useful for teaching about clean agent systems. 

Topics: Featured Article, Featured Blog, MCFP

Featured Download

Subscribe to the Fire Protection Blog