To escape a crash with little to no injury, the car needs to: 1) have space for the driver, 2) keep driver attached to the car; prevent the driver from hitting the interior violently. The car will provide the space; proper seats, belts and padding can provide the rest. Data logging crashes in NASCAR and Indy Cars for the past 20 years has shown that with the proper protection, a driver can withstand over 100 Gs in a crash without severe or fatal injuries. Body support, 6 point belts, head padding, and controlling head motion, are all critical factors.
When you buckle in you are pulling yourself against the seat. Strong, supportive seats with side supports at the pelvis, shoulder, and head are necessary. Chest support is not recommended due to the chance of broken ribs. Belts will hold you in a frontal crash, but seat should provide body support for side and rear crashes. Most seats do not provide this support.
Head and neck restraints depend on the lateral support of your seat to be completely effective. They do not provide protection in a side crash. Because of this need, new standards have been created for Aluminium and Carbon Composite seats: SFI 39.1 and 39.2. The 39.1 seats are quite expensive and are typically found in NASCAR Cup cars; the 39.2 spec seats are more affordable and are mandatory in some series such as ARCA and World of Outlaws. Most road racing seats follow the FIA 8855-1999 standard- these seats are not supported at the upper cage and the test requirement is only 15G. Most of these seats also do not have sufficient shoulder support - there are new seats from Kirkey and Racetech that DO meet the new SFI standards.
|SFI 39.1 'containment' seat|
Why do you need an interior net if you have a good, strong seat? Not all impacts are directly lateral and sometimes there are multiple hits in a wreck. Interior nets, when installed properly, are very effective. They are also very inexpensive, and can make a low-cost seat more effective in a side impact crash. They can also make an inexpensive seat with no lateral head supports more effective by stopping your head from trying to travel across the interior in a side impact. You want to position the net so it catches your shoulder and head as a group- if it catches just your head, it will increase neck compression.
Belts not only help you in a crash, they also help you stay put while you control your car. 6 point belts are recommended over 5 point belts. 6-point belts with double rear-facing crotch straps reduce chest deflection about 50% compared to 5 point belts. They can also reduce neck tension, too (about 15%).
Polyester belts that meet SFI 16.5 can be either 2" or 3" wide - either belt is equally strong! The pressures under either belt are similar - the 2" belts may fit better under your neck restraint as well.
Head and Neck restraint
Belts and seats can effectively restrain the torso, but the head/ neck restraint is needed to control the head. Studies have shown that is you drive a racing car at speeds above 40mph, you need a head restraint. The HANS device and the Hutchens Hybrid by Safety Solutions (now Simpson) perform similarly in SFI 38.1 tests. Either one is a fine choice.
A foam neck collar is NOT a head and neck restraint. They are used to prevent neck fatigue and limit head motion in low-level motions. They could be used in combination with a head/neck restraint, though.
Most leg injuries are from flailing and striking interior surfaces. Flat surfaces with padding on the outside of the leg area can help, and hanging a 'knee-knocker' pad from the steering column can stop painful fractures.
A complete safety system can be obtained for about $2000. This would consist of SFI 16.5 belts, SFI 38.1 Head/ Neck restraint, and a low cost seat with an interior net. How many weeks can you afford to be out of work? What is your health insurance deductible for an ER visit?