Using drop tests -- the typical federal tests used to assess bicycle helmets -- the team found that their air bag helmet could reduce head accelerations by five to six times more than a traditional helmet.
Camarillo believes that the main reason for the improved protection is the large size of the air bag helmet compared to traditional foam bike helmets, meaning it is softer and cushions the impact more.
However, there is a possible downside. The researchers pre-inflated the air bag helmet to the maximum amount before each drop in order to achieve these results, with researcher Mehmet Kurt commenting that, "As our paper suggests, although air bag helmets have the potential to reduce the acceleration levels that you experience during a bicycle accident, it also suggests that the initial pressure that your air bag helmet has is very critical in reducing these acceleration levels."
If the helmet doesn't fill up with the maximum amount of air the results could be very different, and rather than offer more protection it could actually cause the head to hit the ground with much more force than with a traditional foam helmet.
In current versions of the air bag helmet, a chemical process triggers expansion, but this doesn't seem to guarantee maximum air pressure.
The standard bicycle helmet test used in the study also only reveals a helmet's ability to reduce the risk of skull fracture and head injury, and does not directly relate to the risk for concussion. However Camarillo commented that with the positive results and large advantage of the air bag helmet seen in this research, there is a good chance the helmet would also reduce the risk of concussion when compared to a foam helmet.