Is 3D Printer Filament Flammable? Top filaments tested.

There are many filaments on the market today and with great selection obviously not all 3D printer filaments are created equal. Some filaments have wood fibers in them, some filaments have high impact resistance, some filaments are resistant to salt water, some filaments are flexible, and some filaments are not flammable. When it comes to filaments a single feature of a filament doesn’t necessarily make it a worse or better filament, it is just different and special in its own way to achieve a specific task.

ABS and TPU are both popular 3D printer filaments that are flammable. Non-flammable 3D printer filaments include PLA, PETG, PC, and Nylon. All 3D printer filaments are thermoplastics meaning they have the ability to melt and reharden and still maintain most of their material integrity.

There is nothing scarier with 3D printing than the idea of a house fire starting. The most common cause of housefires involving a 3D printer is the thermistor falling from the heating block onto the in-process print and igniting the filament which then can ignite other surrounding items. Below I will explain some of the top 3D printer filaments, their uses, and their ability to resist ignition. 

Is PLA Filament Flammable?

PLA is one of the most popular filaments on the market today. PLA is cheap, easy to print with, made from renewable resources, and from my finding is not flammable when exposed to a flame. 

PLA has a very low melting point and could possibly ignite if put under high heat such as a torch, but would not ignite when exposed to a lighter flame.

There are currently no filaments on the market that are advertised as flame retardant on the market today. There are some Chinese manufacturers that claim to have a “flame retardant” PLA available but non that you can easily purchase in the US.

Is PETG Filament Flammable?

PETG is another extremely popular filament on the market and in my opinion, PETG is the best 3D printing filament due to its strength, heat resistance, durability, ease of use, and as a bonus, it is not flammable like the more popular PLA.

The only downside of PETG is that it has a greater tendency to become brittle when it absorbs moisture. Storing PETG properly is not difficult and can typically be achieved with some desiccant and a cheap air-tight container.

PETG is my absolute favorite filament that is on the market today. It is strong, heat resistant, cheap, somewhat recyclable, and it is very easy to print with. In my eyes PETG will always be the king of thermoplastic filaments!

Overture is one of my favorite PETGs that I commonly purchase and print with.

Is ABS Filament Flammable?

ABS is flammable when exposed to a flame or excessive heat. ABS also emits toxic fumes which can be harmful when inhaled so it is always advised to print in a well-ventilated area. To learn more about filaments that are toxic to inhale check out this article.

ABS is a filament that I personally avoid due to its difficult-to-print nature, delaminating layer issues, harmfulness to the environment, and toxic fumes. In my opinion, PETG is a far superior filament when you need strength and durability. For that reason, I have ditched all of my ABS and choose to not purchase any more in the future, I do still have a single roll of ABS for testing but that will be the last ABS that I will own.

There is flame-retardant ABS on the market such as Form Futura ABSpro and Coex ABS that possess a UL94 V-0 rating for flame retardant ABS. The material will not necessarily have different printing requirements and can be printed on most home 3D printers that have an enclosure.

Is TPU Filament Flammable?

Similar to ABS TPU is highly flammable. TPU is a flexible filament with a very low melting point (lower than PLA) that in most cases requires a direct drive setup to print properly. A stock Ender 3 does not have a direct drive extruder but the machine is fairly simple to convert with a single 3D printed bracket. Follow my guide for more information. How To Convert An Ender 3 To Direct Drive.

Although TPU is flammable if it is ignited it will also melt and produce molten sticky material can cause severe burns to damage the items it comes in contact with. TPU is a less common filament than PLA or PETG but is not any more expensive or harder to find.

Is Polycarbonate (PC) Filament Flammable?

Poly carbonate (PC) is not flammable and will not ignite when exposed to an open flame or even a torch lighter. When exposed to high heat the material will bubble and distort but will not catch fire. Poly carbonate does require a special 3D printer with high heat capabilities to print with so the typical household printer will not be capable of printing PC.

Polycarbonate is one of the strongest thermoplastics on the market today and is commonly used for industrial applications such as electrical devices and household applications such as patio canopies and even eyeglasses. 

Polycarbonate is also widely used for its impact resistance and shatter resistance. Most household 3D printers will not be able to print polycarbonate without a heated chamber and a high-temperature hot end.

Is Nylon Filament Flammable?

Nylon is not flammable and like other thermoplastics will melt rather than catch on fire. The melting point of nylon is about the same as PETG but can be more difficult to print with due to its tendency to shrink. 

Nylon is not a renewable nor recyclable material so it is important for us to stick to materials such as PLA or PETG unless the application absolutely requires Nylon.

When printing Nylon you will need to print at much higher temperatures than would be required with PLA, TPU, or PETG so you will likely want to have a high heat nozzle and an all metal hot end such as the Micro-Swiss all metal hot end.


There are a few 3D printer filaments on the market today that are flammable and there are some choices on the market that are non-flammable. PLA is the most popular filament on the market today that is flammable and although it is flammable it is the only filament that is created from renewable resources and is also one of the simplest filaments on the market today to print with.

PETG is the most popular nonflammable filament on the market, which is my favorite filament to print with due to its strength, durability, and price.

The flammability of material is typically not the cause of a housefire when a 3D printer is involved, so I would not avoid a filament just because of its ability to catch fire.

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