Here’s the chemistry behind it

The extinguishing process involves two different reactions: one is physical and the other, chemical. The physical reaction relates to potassium ions (or Free Radicals) tendency to oxidise rapidly in air. When in contact with air, alkaline salts consume great quantities of oxygen, thus depriving fires of oxygen. Then the chemical reaction is created through the stable link between potassium particles and the fire’s combustion particles.

Through the two reactions, a quick oxidation process takes place, immediately transforming the jet from a solid state into a gaseous state and freeing the potassium particles. These atoms are able to intercept and interrupt any other free particles produced by the fire’s natural chain reaction combustion process.

Potassium has strong inhibitor qualities due to its weak ionization energies. The extinguishing agent being used is composed of Potassium Nitrate, organic oxidizer, and plasticizer resin.

When the Potassium Nitrate (KNO3) reacts (inside the body of the extinguisher) it breaks down and the aerosol that is formed is made up primarily of free radicals of Potassium K+, of Nitrogen N (an inert gas).

The aerosol that comes out of the unit reacts with the fire. Potassium radicals (K+) capture the Oxygen of the combustion thereby extinguishing it.

At the end of the extinguishing process the following is discharged to the atmosphere:

As a solid: particles of Potassium (that have reacted with the Oxygen of the fire) having a size between 3-4 microns. These particles are invisible at sight and heavier than air. They disperse in the atmosphere and tend to deposit on the ground in no appreciable amounts.

As a gas: As Nitrogen; an inert gas already present in the air we breathe at more or less 78%.

As water vapour (and lastly) extremely minimal toxic by-products that are a result of the combustion process. (This amount is so slight, it does not conductive to electricity.

Unlike a dry chemical extinguisher that combats a blaze by depositing a large amount of solid powder on the fire, the Fire Safety Stick fights fire by releasing Nitrogen dioxide (78% of our atmosphere is nitrogen gas) and the active agent, Potassium Free Radicals. This potassium ion attaches itself to the oxygen surrounding the fire robbing its ability to stick to the chain of combustion (without affecting one's ability to breathe that oxygen). The goal is therefore to use the discharge coming out of the FSS to create a ‘cloud of containment’ around a fire. Creating a cloud that prevents any outside and unattached oxygen from getting to the fire is essential and is the same strategy that should also be used with a Halon/Halotron or CO2 extinguisher. The best technique is to take advantage of the long discharge time offered by the Fire Safety Stick and to approach a fire from a moderate distance progressively getting closer to its source. During the approach, move the FSS slowly around the fire always directing it towards the centre, already it will be suppressing the fire from that distance. This will contain the fire and allow the active agent the ability to work. Tight areas with lots of pockets (like the engine bay of a car for example) brings out the strengths of the FSS as the gas, will fill all the voids not directly accessible; both putting out a fire and preventing a re-flash.