TECH TIPS

(25 Jan 2012)

All Driver's Suits Are Not Created Equal - Unraveling the SFI Rating Mystery

Many sanctioning bodies are beginning to require an SFI rated drivers suit, or at least the regulation may have language somewhat like this: "A one piece fire retardant driving suit is required. (Two layer or one layer plus fire retardant underwear minimum - two or three layer suits meeting specifications of SFI 3.2A/5 or FIA 8856-2000 are strongly recommended.)" What exactly does this SFI and FIA stuff mean anyway?

There are two materials that are used extensively in the manufacture of driving suits, Proban and Nomex. Proban is a cotton-based material that has been chemically treated to make it fire retardant. This treatment may diminish with washing. It is used primarily in single layer economy suits although there has been a disturbing increase in manufacturers using it to manufacture inexpensive multi-layer suits.

Nomex is a permanently fire retardant Aramid fiber that is manufactured by DuPont. It is woven or knitted into material by one of several mills in the U.S. Since it is inherently fire retardant its protection does not diminish with time or washing like Proban.

The Proban suit may initially look like a bargain but the life span of the Nomex suit often doubles or triples that of Proban with proper care. Worse yet, it is impossible to tell when Proban may have lost some or all of its ability to protect the wearer in a fire. Northstar Motorsports strongly recommends that all Nomex driving suits be dry cleaned rather than machine or hand washed. This is in accordance with most manufacturers recommendations.

That is why Northstar Motorsports only sells multi-layer suits made from Nomex, and we highly recommend either a three-layer suit with an FIA 8856-2000 rating or a two or three layer suit with an SFI 3.2A/5 rating for all types of racing. Northstar also carries single-layer Nomex suits which we recommend for use only as "over-the-wall crew suits". Even in those applications it is still very wise to wear Nomex underwear under these single-layer suits.

The SFI Foundation is a non-profit organization established to issue and administer standards for specialty/performance automotive and racing equipment. SFI tests a long list of products including gloves, head and neck restraints, suits, shoes, restraint systems, underwear, window nets and roll-bar padding to name a few.

The SFI standards program is funded by participating manufacturers paying for development and administration through licensing and/or unit charges. The SFI specification for drivers suits, Spec 3.2A, rates how long a driving suit will offer protection from second-degree burns in an approximation of a raging gasoline inferno between 1800 and 2100 degrees. SFI ratings are calculated in calories per unit, area per time of exposure. Basically, it gives the buyer a rating system to judge any suits relative protection capabilities. The following table give an approximate time until second-degree burns will occur based on the SFI rating of the drivers suit:

Grade Approx. Time in seconds
3.2A/1 3
3.2A/5 9.5
3.2A/10 19
3.2A/15 30
3.2A/20 40

 

Northstar Motorsports sells the following types of multi-layer Nomex driving suits:

Brand Model Weight* No. Layers SFI rating

Alpinestars

SP

400

2

3.2A/5 & FIA

Alpinestars

GP-T

350

2

3.2A/5 & FIA

Alpinestars

GP Pro

360

3

3.2A/5 & FIA

Alpinestars

GP Tech

300

3

3.2A/5 & FIA

G-Force

545

N/A

2

3.2A/5

OMP

Sport

400

2

3.2A/5 & FIA

OMP

First 2

400

2

3.2A/5 & FIA

OMP

Tecnica Plus 2

320

3

3.2A/5 & FIA

OMP

RE ACT

280

3

3.2A/5 & FIA

OMP

One

280

3

3.2A/5 & FIA

OMP

One EVO

250

4

3.2A/5 & FIA

Sparco

Sprint 6

400

2

3.2A/5 & FIA

Sparco

Pro Cup 10

400

2

3.2A/5 & FIA

Sparco

Sparco

340

3

3.2A/5 & FIA

Sparco

Profy

330

3

3.2A/5 & FIA

Sparco

Superleggera

230

3

FIA Only

Sparco

X-Light EVO 4

290

3

FIA Only

*Weight is in grams/square meter of the multi-layer fabric sandwich.

 

Hyperlinks

ALPINESTARSSP
ALPINESTARSGPT
ALPINESTARSGPPRO
ALPINESTARSGPTECH
GFORCE545
OMPSPORT
OMPFIRST2
OMPTECNICAPLUS2
OMPREACT
OMPONE
OMPONEEVO
SPARCOSPRINT6
SPARCOPROCUP10
SPARCOSPARCO
SPARCOPROFY
SPARCOSUPERLEGGERA
SPARCOXLIGHTEVO4

Tech Tips Archive

Driver Cooling and Hydration (30 Jan 2012)
HANS Devices and Proper Fitting of Helmet Anchors (25 Jan 2012)
New Helmets Required by Most Sanctioning Bodies (16 Aug 2010)
All Driver's Suits Are Not Created Equal (25 Jan 2012)
Toe in or Toe out (4 Apr 1998)
Understanding Tire Temperatures (11 Nov 1997)
Create your own unfair advantage, develop and use a Log Book! (26 Jun 2004)

top of page