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March 23, 2016

Infrequently Asked Questions: Do bike helmets have expiration dates?

The world is full of questions we all want answers to but are either too embarrassed, time-crunched or intimidated to actually ask. In the spirit of that shared experience, we've embarked on a journey to answer all of the questions that burn in the minds of Philadelphians -- everything from universal curiosities (Why do disposable coffee cups still leak?) to Philly-specific musings (How does one clean the Liberty Bell?). 

Helmet replacements aren't exactly high-priority for most bikers -- buy one, and you're set until it shows signs of wear-and-tear. Or, at least, that's the prevailing logic.

Here, David Angel, general manager of Danzeisen & Quigley Sports Specialists in Cherry Hill, Camden County, sets the record straight. 

Do people who ride a bike ever need to replace their helmet?

So, when the Consumer Product Safety Commission started regulating helmet safety, they set a term on the duration of the helmet. It's basically five years, and inside of every helmet there’s a ‘Born On’ date that is now regulated. Effectively, what happens is the foam of the helmet breaks down -- a combination of UV degradation and a fluctuation of temperature and humidity. A helmet is designed like an eggshell, so when it cracks it [spreads] throughout the entire helmet. So if that foam breaks down, it's not going to do the job nearly as effectively. So, five years is the standard lifespan of a helmet.

Any new helmet technology out there?

The big one is called MIPS. That stands for 'multiple impact protection system.' It was developed independently, a few years ago, and it’s been implemented in, initially, downhill mountain bike helmets, then ski helmets and now pretty much everything. The idea behind it is there's a breakaway plate inside of the helmet that’s a little closer to the head than the actual helmet, and it slows down the rotational forces that [act on] the brain, so it doesn’t really help with concussive damage but it helps with hearing, which is basically the brain sloshing on the inside of your skull. That can be just as damaging. It’s been pretty big. Big enough that Giro, the leading producer of bike helmets in the world, purchased a 40 percent stake in the company to license it across everything they produce.

Why do you think people are hesitant to even wear a helmet?

Recreation riders, most people don’t think they’re putting themselves in an area where they’re going to be at risk. They stroll through a park, or sidewalks or things like that where the chances of them getting in an accident or hitting their head is pretty low – or so they assume. Which is not necessarily the case. There’s a lot of things that can happen, and a lot of people who have accidents, accordingly.

What's the takeaway message?

The biggest thing I can stress is getting a properly fitted helmet and always wearing it. We’re in a high-population area with a lot of car traffic, so getting more people out with helmets is a huge thing for us. The chance of it being used is pretty high. Personally, I took a spill two weeks ago and crushed my helmet. No impact to my skull -- didn’t feel it at all. But the helmet is toast. So being in a properly fit helmet is a big thing – making sure the sizing is correct. If it is too large, it can actually cause minor multiple-impacts damage, and you need to be wearing it when you’re supposed to be wearing it. That’s the biggest thing ... As well as reaching bike share communities and things like that, and offer a helmet with what is there. That's a big thing as well.

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