Race Gear How HANS Devices Prevent Injury
The Head And Neck Support (HANS) device was developed by Dr. Robert Hubbard and Jim Downing in the 1980s after studying the biomechanics of basilar skull fractures — the leading cause of death in motorsport crashes at the time. In a frontal impact, the body decelerates rapidly against the harness while the unrestrained head continues forward and snaps back, creating enormous tension on the base of the skull and upper cervical spine.
The HANS device works by coupling the driver's head to the torso via tethers that connect the helmet to the device's shoulder yokes. When the body decelerates, the head is pulled along with it at the same deceleration rate rather than continuing forward independently. The device limits head-forward excursion to approximately 25–30 mm — enough to eliminate the snapping motion that causes basilar skull fracture while still allowing normal head movement during racing.
Documented result: basilar skull fractures and fatalities from frontal impacts in HANS-mandated series dropped dramatically after HANS became mandatory in NASCAR (2001) and F1 (2003). It is among the most significant safety advances in motorsport history.
HANS vs Hybrid Head Restraints
The original HANS device uses a rigid carbon fiber yoke that sits on the driver's chest and shoulders, held down by the harness shoulder straps. The HANS Professional and HANS Ultra are rigid devices — effective, proven, and used in virtually all professional series.
Hybrid head restraints (Simpson Hybrid, Schroth ProFi, RaceQuip HANS) use a semi-rigid or flexible design that allows more adjustment and may be more comfortable for drivers who find the rigid HANS awkward with their particular seat and helmet combination. Key differences:
- Rigid HANS: maximum certified protection, gold standard in professional racing, less adjustable
- Hybrid devices: more position adjustability, often easier to get in/out with, equivalent FIA/SFI ratings available at premium tiers
For club racing, either a certified rigid HANS or a certified hybrid is acceptable — verify the device carries current SFI 38.1 or FIA 8858 certification for your series requirements. Do not use an uncertified device.
Tether Types: Sliding vs Sewn
Helmet tethers connect the HANS device shoulders to anchor points on the helmet. Two main tether designs exist:
- Sliding tethers: the tether slides through an anchor attached to the helmet, allowing some movement while still limiting maximum excursion. Used on most current HANS devices. The tether itself slides through a fixed anchor as the head moves, providing a progressive restraint action.
- Sewn/fixed-length tethers: no sliding; the tether is a fixed length between the device and the anchor. More common in older devices and some hybrid designs.
For almost all club racing applications, the tether type matters less than the certification rating. Buy a device with current certification (SFI 38.1 / FIA 8858-2010 or newer) and verify the tethers are compatible with your specific helmet anchor posts. Damaged, frayed, or kinked tethers must be replaced — they are available as replacement parts from the manufacturer.
Helmet Anchors: What to Look for and How to Install
HANS tethers connect to anchor posts installed in the helmet at the chin bar or lower sides of the helmet. Most modern Snell SA2020 helmets come with HANS anchor posts pre-installed. Older helmets may require aftermarket anchor installation (typically drilled and bonded) — this must be done by the manufacturer or an authorized installer, never DIY with hardware store bolts.
Check these things on your helmet anchors before every race weekend:
- Anchors should be firm with no visible movement when you wiggle them by hand
- The post threads should be clean and undamaged
- The helmet area around the anchor mount should show no cracking or delamination
- The tether clips should click solidly onto the anchor posts with no slop or play
Anchor compatibility matters: HANS tethers and hybrid device tethers use different clip sizes. Verify your tether clips are the correct size for your specific helmet anchor posts. Using undersized clips is a failure point.
Sizing and Fitting a HANS Device
HANS devices come in sizes (small, medium, large, XL) based on shoulder width and in two yoke angles (20° and 30°) based on your driving position. The 20° angle is for more upright seating positions (open-wheel cars, higher seating angle). The 30° angle is for reclined positions (stock cars, sports cars with low-back seats).
Proper fit check:
- The HANS yokes should rest on your shoulders with the shoulder strap of the harness holding them down — the yoke should not slide toward your neck when you tilt your head forward
- With the helmet and tethers connected, you should be able to turn your head approximately 45° left and right without the tether going taut
- The device should not contact your chin or face at any head position during normal driving motion
- The harness shoulder straps should lay cleanly across the HANS yokes without cutting into the carbon material
If you are between sizes, size up — a HANS device that is too large is less effective but safer than one that is too small and digs into your neck. Many distributors offer fitting appointments where you can trial devices in your actual seat with your actual helmet.
