In an interview with Cycling Industry News, Giro's Senior Brand Development Manager Eric Richter says there are "many misconceptions about helmets", and that when it comes to collisions with motor vehicles, it isn't possible to design a bicycle helmet specifically built to protect the user:
“We do not design helmets specifically to reduce chances or severity of injury when impacts involve a car", said Richter.
"... the number of variables is too great to calculate – the speed of the car, the mass, the angle of impact, the rider, the surface, the speed of the rider, did the driver or rider swerve a little or hit the brakes before impact. All of these variables and more are unique in every instance, and there is no way to accurately predict what is going to happen or the forces involved.
“We are mindful of the different types of brain injuries including CTE, and ongoing advances in understanding them. But the common factor in brain injuries is force transmitted to the brain. That common factor is the realm where we have potential to make a difference, and it does not change over time. Therefore we emphasise a simple, unwavering mantra: Less energy to the brain is better protection. On the other hand, the understanding and emphasis around various types of head and brain trauma will continue to evolve, and the effects from an impact or multiple impacts are unknowable variables due to the fact that each impact is a unique event and every rider is unique and changing over time. So, by keeping our primary focus on reducing energy, we keep moving ahead in a way that can theoretically benefit every rider in every impact.”
In answer to the article's question "Are helmet standards overdue a revision?", Richter says that creating new helmet standards to increase rider safety is "much broader and deeper than most people realise", because "no two standards are the same, so different helmets require different test protocols":
“In the last few years, greater emphasis on addressing rotational forces has had a significant impact on helmet design, technology, engineering and testing. Therefore, understanding the effects of rotational motion on the brain, and working to reduce rotational forces by integrating technologies like Spherical Technology and the MIPS Brain Protection System into helmets during the last 5-10 years is the most visible example of how head protection is evolving in response to increased knowledge.”