What is flame retardant?

Are you worried about the risk of fire to your products or property? A small accident can quickly turn into a devastating event, but many materials are dangerously flammable without special treatment.

A flame retardant is a substance added to materials to prevent or slow the spread of fire. It is a critical safety measure that interferes with the combustion process, absorbing heat and isolating the material from the flames.

From my perspective at our aluminum hydroxide plant, I see flame retardant¹s as a form of insurance built directly into a product. We produce a simple white powder, but when it’s added to plastics or textiles, it becomes a silent guardian. The concept sounds straightforward, but how these materials achieve this protection is a mix of simple physics and clever chemistry. Understanding this is key to choosing the right solution, so let’s look closer.

What do you mean by flame retardant?

The term "flame retardant" is everywhere, but what does it really guarantee? This lack of clarity can cause confusion about a material’s actual safety performance in a fire.

By "flame retardant," we mean a functional additive that makes a material more difficult to ignite and slows the rate of burning. It doesn’t make things fireproof, but it dramatically reduces flammability and gives people more time to escape.

The most important goal is increasing safety. A flame retardant’s job is to interfere with what is known as the "fire triangle²"—fuel, heat, and oxygen. If you can remove any one of these three elements, the fire goes out. Flame retardants are designed to attack one or more of these components during a fire. It’s not about making a material invincible. It’s about buying precious time.

The Goal is Escape Time

The key objective is to delay "flashover³." This is the point in a fire where everything in a room bursts into flames at the same time because of the intense radiant heat. By slowing the initial fire on one object, flame retardants can prevent or significantly delay flashover. This gives occupants critical seconds or minutes to evacuate and gives first responders a much better chance of controlling the incident. I always tell my customers that the aluminum hydroxide we supply for their products isn’t just a chemical; it’s a life-saving feature that protects people when things go wrong.

What is fire retardant made of?

You know they are important, but what are these protective materials made from? With growing concerns about chemical safety, choosing the right source is more important than ever.

Flame retardants are made from a diverse group of chemicals. The main families are mineral-based compounds like aluminum hydroxide, halogenated compounds containing bromine, and others based on phosphorus or nitrogen.

In my work, I focus on mineral flame retardants⁴ because they are seen as one of the safest options. Our main product, aluminum hydroxide (ATH), is essentially a purified mineral. It’s a fine white powder that is physically mixed into a material, like plastic, without chemically becoming part of the plastic’s own structure. This is different from other types that react with the material.

A Comparison of Common Types

The trend in the industry is moving toward halogen-free options due to environmental and health regulations. This is where materials like ATH shine. As a direct producer, we can ensure the purity and particle size meet the exact needs for making a safe, effective, and compliant final product. The table below breaks down the main options.

What are examples of flame retardants?

All the chemical names can sound abstract and confusing. It’s much easier to understand their importance when you see where they are used in products around you.

Common examples include Aluminum Hydroxide (ATH), which is widely used in the insulation for electrical cables. Brominated flame retardants (BFRs) are often found in the plastic casings of electronics like TVs and computers.

Seeing our product used in a final application is always fascinating. One of our biggest markets is for wire and cable manufacturers. They buy our aluminum hydroxide powder and mix it directly into the PVC or rubber that insulates the copper wires. A simple electrical short circuit could easily start a fire, but because our ATH is in the insulation, the fire is suppressed immediately at the source. It prevents a small problem from becoming a catastrophe. This single application protects homes, offices, and industrial facilities all over the world.

Safety in Everyday Objects

Beyond cables, our ATH and other flame retardants are used in many places:

• Construction: In wall panels, roofing membranes, and flooring to meet strict building safety codes.
• Transportation: In seats, carpets, and plastics for cars, trains, and airplanes to slow fire spread and give passengers time to exit.
• Electronics: While BFRs have been common, there is a strong push to replace them with halogen-free options⁵ like ATH in plastic housings and circuit boards. This is driven by buyers who want safer, more environmentally friendly products.

How do flame retardants work?

We know they stop fire, but how do they actually do it? The science seems like it would be very complicated, but it’s based on very direct principles.

Flame retardants work through physical or chemical actions. Some cool the material by releasing water vapor. Others form a solid insulating char layer. A third type releases chemicals that disrupt the chain reaction of fire in the gas phase.

This is my favorite part to explain, because our product, aluminum hydroxide, has a particularly elegant and effective way of working. It uses a physical mechanism that is simple, powerful, and safe. It’s not a complex chemical trick; it’s a basic endothermic reaction⁶.

Cooling, Diluting, and Shielding

When a material containing aluminum hydroxide (ATH) is exposed to fire, it starts to break down at around 220°C. The chemical reaction is simple: it decomposes into aluminum oxide and water vapor. This process does three things at once to fight the fire:

1. Cooling: The reaction is endothermic, meaning it absorbs a large amount of heat energy. This cools the plastic or rubber, keeping it below the temperature it needs to keep burning. It acts like a built-in heat sink.
2. Dilution: The reaction releases a lot of water vapor. This water vapor dilutes the flammable gases that the burning material produces, making the air-fuel mixture too lean to ignite easily.
3. Shielding: The aluminum oxide left behind is a non-combustible ceramic material. It forms a protective char layer on the surface of the material, acting as a shield that insulates the underlying material from heat and oxygen.

Conclusion

A flame retardant is a critical safety additive. It works by cooling, isolating, or disrupting combustion to slow or stop the spread of fire, ultimately saving lives and property.