The Snell Memorial Foundation is a not for profit organisation based in the USA committed to improving the performance of crash helmets. It was established in 1957 in response to the tragic death of Peter Snell in a motorsport accident. Its goal? To ensure helmets offer an adequate level of safety performance to the user – and to help manufacturers make them safer.
Since then, it not only tests helmets that are on general sale but offers different certificates for motorsport, motorcycle and karting helmets (denoted by letter SA, M and K). It also works with manufacturers to help them develop helmets that will pass its standards and bring compliant helmets to market – which are then allowed to display the Snell certification sticker on them.
So what does the Snell helmet test include?
The test has developed over the years and you can see which test each helmet passed by the date in the certification. The first standard for motorcycle helmets was M2000 (in the year 2000) and the latest is M2015. To find a full list of which helmets are Snell certified, visit their certification page. And where a helmet we’ve reviewed is Snell certified, we’ll also put it on our review page.
Below is what’s tested in the M2015 certification test:
1. The first test is an impact test. A helmet is fitted with a suitable dummy ‘headform’ that includes an accelerometer (or should that be decelerometer?). The helmet is then dropped against a range of different surfaces to simulate different types of impacts. The helmet needs to absorb enough energy to ensure the accelerometer measures no more than around 300 Gs – there’s slight deviations depending on which standard is being tested (but that’s still an awful lot of decelleration!).
2. Next is a test designed to check whether the helmet is secure on the head and won’t come off during an accident. As an aside, independent research seems to indicate that helmets come off in around 5% of accidents – probably through badly fitting helmets or straps that are incorrectly adjusted (or not fastened at all). Snell affixes a cable to the rear of the helmet, tilts it to an angle of 135 degrees then drops a 4Kg weight to simulate a force trying to rip the helmet off the head. They then repeat the test to the front of the head. A helmet can move, but must remain on the head to pass the test.
3. The next test tests the performance of the retention strap. A 23Kg weight is attached to the strap for one minute. If that’s passed, the 23Kg weight is replaced by a 38Kg weight which is then dropped to stress the strap and closing mechanism to ensure it won’t break or stretch more than 30mm. If it does, it fails.
4. The fourth test is the chin bar test – where a helmet is fixed to a solid base with the chin bar facing upwards and a flat 5Kg weight is dropped onto it. The chin bar must not break or bend beyond a certain amount.
5. The penultimate test involves dropping a 3Kg spike onto the helmet to check it can resist penetration.
6. The final test checks the face shield is resistant to penetration by firing an air rifle pellet at it at a speed of around 500 kph.
When a helmet passes the tests, the manufacturer can then display the Snell logo on the helmet – as a sewn-in label an on the back of the helmet. However, that’s not the end of the process. Snell conducts random sample testing on the retail versions of each certified helmet by purchasing helmets throughout the manufacturing run of the helmet to ensure it continues to pass the tests. If samples fail, there are a number of steps Snell will take – from demanding the manufacturer remedies the product to full decertification of the helmet.
Potential issues with Snell helmet testing?
Like any helmet testing regime, there are a few detractors of the Snell testing regime.
Firstly, there’s a slight question mark over some of the science behind their tests and opponents suggest that it doesn’t reflect real-world motorcycle accident data enough. They also point out their testing can result in a helmet with a shell that’s simply too hard to effectively reduce the shock being passed through to the brain. Latest crash helmet design thought is that the helmet shell needs some flex in it to help it absorb the impact shock and stop it passing through to the skull and brain. Stopping shock passing through to the brain is very much one of the main objectives of an effective crash helmet. If a shell is too hard, it can’t help with absorbing shock and leaves only the EPS liner to do the job.
There’s also not much evidence that helmets are likely to suffer from penetration to the shell – one of the lab tests a Snell certified helmet has to undergo.
That said, there seems to be no doubt that Snell are entirely committed to improving crash helmet safety and are working hard to improve safety standards for helmet users in the US. We’ll therefore leave you to make your own mind up as to whether you want to buy a Snell certified helmet and will simply report where a helmet is Snell certified.
We’ll also report where a helmet is SHARP tested and when it’s either DOT certified or ECE 22-05 approved. Reporting on all these schemes, we hope to provide our readers with the fullest view of how well each crash helmet will perform.
Here’s more information on The Snell Foundation or here for our analysis of SHARP testing data to find out more about how protective different types of helmet are along with lots of other useful information.