Recently, the Toronto Cycling Committee and CAN-BIKE members were invited on a tour of the Canadian Standards Association (CSA) Helmet testing facilities. The tour included all sorts of fascinating facts about what a helmet has to go through before you can pick it up on a store shelf.
The CSA conducts about 1800 different types of tests in the 250,000 sq. ft facility. The test we witnessed dealt with bicycle helmets.
First, the helmets undergo a chin strap test. The test involves a 7Kg weight being preloaded on the strap and dangled about a metre below. The weight was then raised up towards the helmet by hand and dropped where it met a stopper. This test was designed to make sure the strap and buckle didn't stretch, slip or break. Additionally the helmet should not show any fatigue.
The second test included a drop test of a helmet to test 6 different impact points. The front, rear, left and right sides, top, and ventilation holes would be tested from a typical rider height plus a calculated distance (mass, gravity, velocity). The test would then be repeated for 5 different sizes of the human head from children to adults. In each test the impact force is never to exceed 2.5 G's. With children's helmets the impact force must never exceed 2.0 G's -- childrens helmets have additional expanded polystyrene (EPS) to absorb the impact and adjust for the still-forming skull.
When buying a helmet for a child it is important to note that children's helmets are different than adult's helmets. Children's helmets have additional expanded polystyrene (EPS) to absorb the impact and adjust for the still-forming skull.
EPS foam does have a shelf life and that is adjusted depending on the materials (check your manufacturer for helmet details), the CSA approval exists for the creation date of the helmet. Typically helmets have a limit of 5 years or a single impact.
EPS foam also changes in its effectiveness depending on weather conditions. Your helmet best works in warm weather. Cold weather makes the foam more rigid. One of the biggest threats to your helmet is bug spray. DEET can eat away at the foam and make it structurally unsound.
Currently the CSA has recognition in Canada, US, and elsewhere internationally. So the logo on the inside of your helmet carries some weight with it. Not enough to slow you down, just keep you safer.
For more information on Helmet Safety please see the CSA's Head Smart PDF brochure.