Here is some info. I put together from various sources on helmet ratings:
There are two main organizations, SNELL & DOT that certify helmets for minimum safety standards. Helmets can be Snell certified only, DOT Certified only or both. Most helmets that you would consider using for auto racing need to be SNELL approved! But, each track varies & some will only require DOT certification. DOT certification is usually associated with motorcycle type helmets. Almost all helmets sold today are approved by one of these organizations.
Although Snell requires helmets to withstand substantially larger impacts while transmitting less force, each organization performs basically the same types of tests for a variety of criteria:
SNELL:
The Snell Memorial Foundation is a not-for-profit organization dedicated to research, education, testing and development of helmet safety standards.
Although Snell has several helmet standards, the two most common are:
SA = Standard designed for auto racing
M = Standard designed for motorcycling and other motor sports
There are three major differences between the standards:
1. SA standard requires flammability test while the M standard does not
2. SA standard allows narrower visual field than M standard
*note that some SA helmets may not be street legal
3. SA standard has roll bar impact test while M standard does not.
The Snell foundation was created due to the death of an amateur auto racer named William "Pete" Snell who died needlessly in a racing event in 1956 when his then state-of-the-art helmet failed utterly to protect him.
Snell updates their safety standards every five years and is considered the most demanding, the last time being the year 2000. Currently, helmets with the Snell M2000 or SA2000 rating meet the latest Snell standards. The new standards, that have already been written, will be launched in 2005. In order for a helmet to receive a Snell certification, manufacturers apply for and earn Snell certification. Snell bills the manufacturer for testing, the acquisition of random samples and for each Snell Certification label that goes into a certified helmet.
You can find more in depth information on the Snell Foundation here: http://www.smf.org/
DOT:
Federal Government?s Department of Transportation:
DOT 218 means that the helmet meets standard number 218, which was specifically designed for motorcycles. The standard is Federal Motor Vehicle Safety Standard 218 (FMVSS 218) and is known commonly as the DOT standard.
DOT certification is done on the honor system. The helmet?s manufacturer determines whether his helmets satisfy DOT and then claims the qualification for himself. There is not even a reporting requirement. The government does contract for some spot check testing at commercial and private labs but not very much.
Seeing that Snell provides more stringent testing on helmets & exceeds the DOT standard, a Snell certified helmet is the best assurance of protection for your head in an accident. However, a DOT rated helmet is by no means a bad helmet. There is just no gaurentee that the DOT standard has been met by the manufacturer.
It is recommended that helmets are replaced every three to five years depending on the intensity and frequency of use. Helmets are often dropped and banged around as we use them. This can cause the shell & liner protection effectiveness to be compromised especially if there are any cracks or compressions in the liner and/or spidering can be seen on surfaces of the liner. Also with heavy use, the glues, resins and other materials used in helmet production can breakdown over time. General liner deterioration from Hair chemicals, body fluids, cosmetics & normal ?wear & tear? of a helmet over time will all contribute to helmet degradation and could cause the padding to contract or compact making the helmet fit too loose. A helmet should fit comfortably tight squeezing your cheeks a bit without giving you a headache.
There are two main organizations, SNELL & DOT that certify helmets for minimum safety standards. Helmets can be Snell certified only, DOT Certified only or both. Most helmets that you would consider using for auto racing need to be SNELL approved! But, each track varies & some will only require DOT certification. DOT certification is usually associated with motorcycle type helmets. Almost all helmets sold today are approved by one of these organizations.
Although Snell requires helmets to withstand substantially larger impacts while transmitting less force, each organization performs basically the same types of tests for a variety of criteria:
- Retention strength
- Stability - How well the helmet will stay on
- Penetration resistance
- Impact resistance
- Chin guard strength (if applicable)
- Face shield integrity (if applicable)
- Heat resistance - The ability to withstand fire
- Impact energy management - Of course, the most important
- Most helmet standards also have requirements for coverage and visual clearances too
SNELL:
The Snell Memorial Foundation is a not-for-profit organization dedicated to research, education, testing and development of helmet safety standards.
Although Snell has several helmet standards, the two most common are:
SA = Standard designed for auto racing
M = Standard designed for motorcycling and other motor sports
There are three major differences between the standards:
1. SA standard requires flammability test while the M standard does not
2. SA standard allows narrower visual field than M standard
*note that some SA helmets may not be street legal
3. SA standard has roll bar impact test while M standard does not.
The Snell foundation was created due to the death of an amateur auto racer named William "Pete" Snell who died needlessly in a racing event in 1956 when his then state-of-the-art helmet failed utterly to protect him.
Snell updates their safety standards every five years and is considered the most demanding, the last time being the year 2000. Currently, helmets with the Snell M2000 or SA2000 rating meet the latest Snell standards. The new standards, that have already been written, will be launched in 2005. In order for a helmet to receive a Snell certification, manufacturers apply for and earn Snell certification. Snell bills the manufacturer for testing, the acquisition of random samples and for each Snell Certification label that goes into a certified helmet.
You can find more in depth information on the Snell Foundation here: http://www.smf.org/
DOT:
Federal Government?s Department of Transportation:
DOT 218 means that the helmet meets standard number 218, which was specifically designed for motorcycles. The standard is Federal Motor Vehicle Safety Standard 218 (FMVSS 218) and is known commonly as the DOT standard.
DOT certification is done on the honor system. The helmet?s manufacturer determines whether his helmets satisfy DOT and then claims the qualification for himself. There is not even a reporting requirement. The government does contract for some spot check testing at commercial and private labs but not very much.
Seeing that Snell provides more stringent testing on helmets & exceeds the DOT standard, a Snell certified helmet is the best assurance of protection for your head in an accident. However, a DOT rated helmet is by no means a bad helmet. There is just no gaurentee that the DOT standard has been met by the manufacturer.
It is recommended that helmets are replaced every three to five years depending on the intensity and frequency of use. Helmets are often dropped and banged around as we use them. This can cause the shell & liner protection effectiveness to be compromised especially if there are any cracks or compressions in the liner and/or spidering can be seen on surfaces of the liner. Also with heavy use, the glues, resins and other materials used in helmet production can breakdown over time. General liner deterioration from Hair chemicals, body fluids, cosmetics & normal ?wear & tear? of a helmet over time will all contribute to helmet degradation and could cause the padding to contract or compact making the helmet fit too loose. A helmet should fit comfortably tight squeezing your cheeks a bit without giving you a headache.
