In the United States there are two major organizations responsible for establishing the safety standards of racing equipment. They are the SFI and the FIA. For racing harnesses the SFI has established the SFI 16.1 and SFI 16.5. And the FIA uses the FIA homologation standards 8853-98 and 8853-2016.
Check the rules of your sanctioning body for which standards apply.
The FIA is an organization that is based in France and provides rules and regulations for most international forms of racing including F1, World Rally and World Touring Car Championship.
The SFI is a US based non-profit organization that issues and administers standards for racing equipment including safety equipment.
Aside from price there are some differences between the standards that it helps to understand before making your purchase. One of the major differences is the length of time that each harness is valid for. An SFI rated harness has a tag with the month and year of manufacture. SFI certifies that the harness will meet the safety requirements from 2 years of this date. After this date, the SFI will no longer certify that the harness meets the safety standards.
An FIA harness has a tag with the year of manufacture, and they certify the harness meets the safety requirements from 5 years of this date. It is possible to get 6 years from an FIA rated harness however. For instance, an FIA harness stamped 2017 and purchased in January of 2017 will actually be good for 6 years until Dec. 31, 2022.
A primary reason for the expiration dates is damage from UV light, water, oil and other contaminants on the harness webbing material.
FIA harness webbing is made from polyester, while SFI harness webbing is typically made from nylon.
Polyester webbing has a superior resistance to the listed contaminates and helps contribute to its increases longevity over the nylon material of the SFI harness.
Polyester webbing also has a superior resistance to elongation. Nylon may elongate up to 25%, whereas the polyester webbing can be designed to stretch anywhere from 6-16%.
SFI 16.1 testing applies a load over the body block of 5,750lbs each on the lap and shoulder belts and over the complete 5 or 6 point assembly. Webbing test (breaking load) must meet 6,300lbs for laps and shoulders and 1,500lbs for sub straps such as anti-submarine belts.
SFI 16.5 testing applies a load over the body block of 11,000lbs over the complete 5 or 6 point assembly. Webbing test (breaking load) must meet 7,000lbs for laps, shoulders and sub straps. Additional tests include a Roller Adjuster Micro-Slip Test, and Webbing Abrasion Test.
Shown is a table showing the FIA requirements for 8853-98 and 8853-2016. For reference, 1kN = 225 lbs.
Image courtesy of SCHROTH Safety Products, LLC
The typical operating environment of an SFI harness is also different from an FIA harness.
SFI belts are more common in drag racing and circle track racing and are often exposed to elements such as mud, water, and oil.
At these events, the entire car is typically hosed off, including the harness, and the harness is then left exposed to direct sunlight.
SFI testing for these conditions has determined that the harness cannot be used safely for more than two years.
FIA belts last longer because of the webbing material being made from polyester, and that the typical FIA operating environment is less harsh than what a typical SFI harness will experience.
FIA testing and approval procedures are more costly – therefore FIA belts are typically more expensive than SFI belts.
Over the useful life of a harness system, the price of an FIA belt, with up to six years of validity compared to the multiple sets of SFI belts that would be needed may end up at a break-even or less expensive than the SFI belts over the same period of time.
For more information we’ve attached links to the SFI and FIA standards below so you may view them for yourself. (As of date of publish of this article, these are the links for the current SFI and FIA standards for harnesses).