PyroBubbles® Explained: The Glass Granules Rewriting Fire Suppression

When most people think of fire extinguishing, they picture water, foam, or a dry powder. All of these have served industry well for decades. But each comes with significant drawbacks — water causes damage and can react violently with certain fires, foam is increasingly regulated as an environmental contaminant, and dry powder leaves a corrosive residue that can destroy sensitive equipment. PyroBubbles® take a fundamentally different approach. Rather than chemically reacting with the fire, these tiny borosilicate glass spheres work through a combination of physical mechanisms that together make them one of the most versatile fire suppression media available. What Are PyroBubbles®? PyroBubbles® are hollow, porous granules made from expanded borosilicate glass — the same base material used in laboratory glassware and heat-resistant cookware. They look and pour like coarse sand, but weigh around five times less: approximately 250 kg/m³ versus 1,300 kg/m³ for conventional sand. This low bulk density makes them easy to handle and reduces the structural load on storage containers. The granules are produced in consistent size grades and are chemically inert. They do not oxidise, do not absorb moisture, and do not react with the materials they are used to protect. Once a fire is extinguished, uncontaminated PyroBubbles® can be recovered — by vacuum or shovel — and reused. Four Mechanisms Working Together The effectiveness of PyroBubbles® comes from four simultaneous physical processes, each addressing a different aspect of fire suppression. Inerting: When poured or deployed onto a burning surface, the granules form a dense interlocking layer. This close packing physically obstructs the flow of oxygen and combustible vapours, preventing the fire from sustaining itself. Cooling: Borosilicate glass has a high specific heat capacity. As the granules absorb heat from the fire, they reduce the temperature of escaping gases and vapours to below their ignition point, preventing re-ignition. Condensation: Flammable vapours that pass through the granule layer are cooled below their boiling point and condense onto the glass surface, effectively removing them from the gas phase where they could otherwise ignite. Adsorption: The porous microstructure of each granule dramatically increases its surface area. Vapours and liquids are drawn onto this surface and held there, rendering them safe for disposal. Applications Across Industries These properties make PyroBubbles® effective across a wide range of fire scenarios that would challenge conventional agents. For metal fires — magnesium, aluminium, and similar materials that burn at temperatures exceeding 2,000°C — PyroBubbles® melt to glass at those extreme temperatures and form a sealed, self-healing layer over the burning material. Unlike metal fire powder, they leave no oxidising residue, so nearby metal components do not corrode. For flammable liquid fires, the granules float on the burning surface and spread to form a uniform heat-absorbing layer. Unlike foam agents, they work on polar solvents such as alcohols and ketones, and are safe for use in live electrical installations. For lithium-ion battery fires, where thermal runaway makes conventional suppression almost impossible, PyroBubbles® interrupt the chain reaction by simultaneously cooling, inerting, and absorbing the combustible gases being released by failing cells. Environmental and Operational Benefits Because PyroBubbles® are chemically inert and non-toxic, they are classified as non-hazardous waste. There is no environmental contamination risk from runoff — a significant advantage over AFFF foam agents, which are subject to increasingly strict regulation globally. The reusable nature of the product also reduces long-term costs and the carbon footprint associated with re-stocking after a fire event. For South African businesses looking to modernise their fire protection infrastructure, PyroBubbles® offer a compelling combination of performance, environmental responsibility, and operational simplicity. Contact the Pyro Brand team to discuss how they can be integrated into your existing fire protection strategy.