One of the most important pieces of safety gear for race car drivers is a fire suit. The purpose of a racing suit is to protect the wearer, whether a driver or pit crew member, from fire, extreme heat, and abrasions in the event of an on-track accident. When choosing a racing fire suit, look for key features that balance safety, comfort, and performance. A proper fit, up-to-date safety certifications, and compliance with track regulations are essential. The best racing suits for both amateur and professional drivers are durable and comfortable, with extras that make them more functional, like better mobility, cooling features, or custom styling designed for your specific racing environment and driving style.

This auto racing suit buying guide covers what to look for, including certification requirements, comfort features, and sizing, so you can get the right level of protection and performance.

What To Look for in a Racing Fire Suit

When it comes to fire-retardant clothing, your suit is a high-priority item that must meet stringent standards. With so many options available, it can be difficult to know what to look for. Consider the following features and how they fit your preferences and gear setup:

• Two-piece jacket and pants sets vs. full-body options, based on comfort and mobility
• Easy-to-use zippers, closures, and fasteners for quick dressing and removal
• Built-in cooling features to help manage heat during long sessions
• Compatibility with your existing safety gear, such as HANS devices or head socks
• Integration with neck restraints, belts, and seat types
• Sewn-in stretch panels for flexibility and range of motion
• Adjustable cuffs, waist, and collar for a personalized fit
• Added style, color options, or embroidered details for a more custom look

Trust the options available from the best brands in the industry, including Impact, RaceQuip, K1 Race Gear, MPI, and Simpson, and choose the style that fits you best.

Certification Requirements

Just like with buying a helmet, it’s important to check your fire suit’s certification to be sure it meets the rules for the kind of racing you do. Most racing suit certifications come from either the SFI Foundation or FIA (Federation Internationale de l’Automobile). These organizations independently test suits to make sure they can protect against heat and fire in the event of an accident.

Tests measure how much heat a suit can handle over time, and how well it protects you from second-degree burns. You might also see a TPP (Thermal Protective Performance) rating, which tells you how long you could be exposed to fire before injury occurs.

What SFI Rating Do I Need?

Common certifications include SFI 3.2A/1 (SFI-1), SFI 3.2A/5 (SFI-5), and FIA 8856-2000. In SFI ratings, the final number tells you how long the suit offers thermal protection with a higher number indicating a longer protection time. 

To find out which rating your fire suit needs, check the rules from your track or sanctioning body. They’ll list the minimum required rating so you can choose one that meets their standards and keeps you compliant. If you race internationally, keep in mind that most tracks outside the U.S. follow FIA certification. You may need a separate FIA-approved fire suit or choose one that’s certified by both FIA and SFI to cover all your bases.

Current Fire Rating for Racing Suits

The fire rating for a racing suit refers to how long it can protect the wearer from second-degree burns during direct flame exposure. The chart below breaks down current SFI ratings and the approximate number of seconds each provides before a second-degree burn can occur.

Note: While the minimum SFI rating is often accepted at circle tracks, higher ratings, such as SFI-15 or SFI-20, are typically required for drag racing due to increased fire risk. Always check with your track to ensure your suit meets the specific safety requirements.

Material Type, Thickness, and Weight

One of the biggest differences you’ll notice between fire suits is how thick and heavy they feel. Higher-end options are usually lighter and thinner, even with higher SFI ratings, which makes them more comfortable and less restrictive during long stints in the car.

But it’s not just about weight. Comfort also depends on things like the cut, materials, and overall construction. A few key factors that affect how a suit wears and performs include:

• Number of protective layers
• Type of fire-resistant materials used
• Quality of stitching, zippers, and closures
• Integrated padding or reinforcements

Top-tier race car driver suits often include stretch panels in the lower back, arms, and waist to improve flexibility and make it easier to move. Moisture-wicking and cooling properties also help, especially in hot cockpits or longer races where heat buildup can lead to fatigue. A lightweight, breathable suit can make a big difference in comfort and focus, especially when paired with moisture-wicking base layers or a cooling system.

If you're on the sidelines, whether part of the pit crew or support team, you may be able to prioritize comfort and mobility over a higher SFI rating. Just be sure to follow your track’s uniform rules, and choose gear that meets or exceeds the minimum required fire protection.

Nomex® Versus Flame-Resistant Cotton

Nomex® is a high-temperature-resistant fiber that doesn’t melt when exposed to flame. It acts as an effective barrier against heat, giving drivers valuable time to escape in the event of a fire.

Flame-Resistant Cotton (FRC) and Flame-Retardant Treated (FRT) cotton are made from cotton materials that are chemically treated to resist ignition. While they also protect against heat and flame, their flame-retardant properties can fade over time.

Both materials are washable, but longevity differs: cotton suits typically last up to 50 washes, while Nomex suits can handle up to 125 washes or around five years of use, making Nomex the longer-lasting investment.

One-Layer Versus Two-Layer Suits

When deciding between one-layer or multi-layers, consider cost, how often you race, and any track requirements. One-layer suits are typically lighter, more affordable, and commonly used for entry-level or occasional racing. Two-layer suits provide added insulation and fire protection, making them the standard for most professional race series and many sanctioned events.

Three-layer suits are also available, but more layers don’t always mean more safety. The safest options are made with high-quality fire-resistant materials and meet recognized SFI certifications, regardless of the layer count.

Size and Fit

A proper fit is essential for both safety and comfort, allowing better movement and control behind the wheel. When determining your ideal size, look for options that provide a comfortable, slightly loose fit with room for movement. Suit cut, material type, and construction all play a role in overall comfort.

Modern suits from K1, Simpson, and Impact are trending toward a more “European” cut, which is tailored and closer-fitting, rather than baggy. When trying on suits, consider more than how it feels while standing. It should fit comfortably while you’re sitting in race position, as well as when you’re walking, reaching, and moving throughout the day.

How to Determine the Best Racing Suit Size

Fit can vary between brands, so it’s best to measure, or be professionally measured, before buying. Use a flexible tape measure (or string and a ruler) and record the following:

• Chest: Around the fullest part, under the arms
• Waist: Around the natural waistline (across the navel)
• Hips: Around the widest part of the hips
• Height: From floor to top of head while standing straight
• Inseam: From ankle bone to crotch (inside leg)
• Thigh: Around the thickest part of the thigh
• Arm: From wrist bone to shoulder with arm extended
• Neck: Around the base of the neck, where a collar rests

Compare your numbers to brand-specific size charts to determine the best match for your body type. Then try on various suits across styles and brands to find what feels best. Always wear any fire-resistant base layers you’ll use under the suit when testing fit to ensure accuracy.

General Suit Sizing Reference (Estimate Only)

Note: Use this chart as a general guideline only. Always compare your measurements to the official size chart for the brand you're purchasing.

Custom Racing Fire Suits

Some brands offer custom-built racing fire suits tailored to a driver’s individual measurements. These can be provided by the customer or taken in-house by a Behrent’s professional for optimal accuracy. Custom options not only offer a personalized fit, but also give you control over design, color, and embroidery. You can choose from a variety of stretch panels, gussets, pockets, linings, and shell materials to meet your specific comfort, style, and safety preferences. Contact Behrent’s to find the custom style that fits your build, your brand, and your goals.

The experts at Behrent’s can help you with your safety gear questions, from sizing and fit to keeping your racing suit clean. When you're ready to suit up, trust Behrent’s Performance Warehouse for race-day protection that fits right, feels right, and meets the demands of the track.