Nomex® vs Proban®: Which Fire-Resistant Racing Suit Fabric Is Right for You?

Two ways to make fabric fire resistant

There are two broad ways to make a fabric resist fire. The first is to use a fibre that is inherently flame resistant — it will not melt or drip and it chars rather than burning. The second is to take a natural fabric such as cotton and give it a flame-retardant treatment that changes how it behaves in a fire.

Nomex® belongs to the first group. Proban® belongs to the second. Both are used in certified racing suits, but they suit different budgets, ratings and drivers.

Nomex®: protection built into the fibre

Nomex® is a meta-aramid fibre. Its flame resistance is a property of the fibre itself, so it does not wear off or wash out over the life of the garment. It is also light for the protection it gives, which is why it is the standard fibre for multi-layer professional race suits.

Our two-layer Nomex® suit system combines a 150 g/m² outer shell with a 180 g/m² inner layer — 330 g/m² in total — and achieves SFI 3.2A/5 with a TPP rating of 21.6. Nomex® also takes colour well: suits can be made in any shade from our Nomex colour chart, including fluorescent colours.

Proban®: treated cotton for an affordable certified suit

Proban® is a durable flame-retardant treatment applied to cotton. The result feels like a cotton garment — soft, breathable and familiar against the skin — while resisting ignition and self-extinguishing when the flame source is removed.

Our single-layer SFI 3.2A/1 suits use 295 g/m² Proban® FR cotton with a TPP rating of 10. It is the entry point into a certified suit and a sensible choice where a series asks for the base SFI rating: club racing, drag racing and track days.

Side-by-side comparison

Here is how the two constructions we manufacture compare:

• Rating: Proban® single layer — SFI 3.2A/1. Nomex® two-layer — SFI 3.2A/5.
• TPP: Proban® — 10. Nomex® — 21.6.
• Fabric weight: Proban® — 295 g/m² single layer. Nomex® — 330 g/m² across two layers.
• How it protects: Proban® — flame-retardant treatment on cotton. Nomex® — inherent in the fibre.
• Feel: Proban® — soft, cotton-like. Nomex® — light and smooth, with a more technical feel.
• Price: Proban® is the lower-cost route to a certified suit; Nomex® costs more but gives a higher rating.

The weight figures show why layering matters: the Nomex® system is only slightly heavier per square metre in total, yet more than doubles the TPP because the two layers trap insulating air between them.

Which one should you choose?

Choose Proban® if your series requires SFI 3.2A/1, you are equipping a large group of club or junior drivers, or you want a comfortable certified suit at a lower price.

Choose Nomex® if your series requires SFI 3.2A/5, you race faster cars or longer stints, or you want the lightest suit for the protection level and the widest choice of bright colours.

Whichever you choose, wear fire-resistant underlayers beneath it. Our Nomex® knit underlayer range covers base layer tops and trousers, boxers, socks and balaclavas.

Caring for each fabric

Both fabrics need the right care to keep their protection. Contaminants such as oil and fuel are flammable and must be cleaned out, and chlorine bleach and fabric softener should be avoided. Treated fabrics such as Proban® are particularly sensitive to the wrong washing products. Read our full guide on how to wash and care for a fire-resistant racing suit.

Compare every material we use

Our materials library lists every fabric we build racewear from — including the non-fire-resistant fabrics used for karting suits, rental suits and teamwear — with weights, ratings and the products each one is used for. Ready to order? Request a quote and tell us the rating your series requires.