People shopping for helmets normally come at it from one of two directions: either they want to get the most expensive protection they can buy or they want the cheapest thing available since they don’t think they will ever actually ‘need’ it. Neither is necessarily a good approach and it comes about because most people don’t really understand what makes for a good helmet. So let me explain a little and then hopefully the enlightened reader can make choices based on better information…
If you think hitting your head is unlikely that is the same as saying that it is possible – so be prepared with a proper helmet. If you like your head then you should make sure that whatever is protecting it will do the job when the situation demands. Sure, some people are doing things that are more likely to result in a good bonk – like kayaking class V rivers. But it is not about likelihood – it is about preparing for worst case scenario. If you have a helmet on your head you need to make sure that it is not just there for show – it has to work.
The first thing required for a helmet to do its job is that it must fit properly – if it doesn’t stay on your head it cannot protect it. Most modern kayak helmets come in a variety of sizes or with multiple fit pads and several different adjustment points. If you take your time – and it may take up to an hour to tweek a helmet to perfection – you can get most helmets to fit well. That means they are snug all around but don’t have pressure points, the chin strap is tight so the helmet can’t get pushed back off your head, and when your head moves the helmet moves with it. Different models will fit different heads differently so TRY IT ON and take the time to adjust it.
After fit comes construction. Helmets basically consist of two parts – a hard shell and foam padding. Let’s look at the foam first – it is actually the thing that absorbs the energy in an impact and in many regards is most important. All kayak helmets are designed to handle multiple impacts – the foam should spring back after a hit and be ready for another. If you are used to the stiff foam of a bicycle helmet that is a single impact design – it absorbs more energy but only works once. For kayaking you want a stiff foam that will absorb energy but also something that will be comfortable. Many designs have both – a stiff foam inside the helmet with a lining foam (or pads) that will be softer next to your head. More foam generally equals more energy absorption (but it also depends on the type and density of the foam).
The job of the outer shell is to distribute the force of any impact so that more of the foam can absorb energy. To do this stiffer shells are generally better – if they flex too much a pointy rock will load up a small section of foam and more energy will make it through to your noggin. For materials the composite shells are generally stiffer and lighter – carbon being the ultimate material but fiberglass shells being quite stiff if a little heavier. Plastic shells are significantly cheaper and generally more flexible but can be made stiff through design and reinforcements. Some helmets use a blend of composite reinforcing plastic to find a good mix of stiffness and price.
An interesting note is that when a large array of motorcycle helmets were tested the plastic helmets did just as well as the composites – it was the quality and thickness of the foam that determined how well the helmets performed. Of the different types of foam used EPP (Ethyl Polypropylene) was the best but also the most expensive. But those tests were done with impacts on flat objects instead of pointy ones – the theory is that stiffer, stronger shells make a difference in sharp impacts.
So if you need a helmet make sure to get a good one – one that fits you well, will handle the conditions you face and keep you from getting your bell wrung. Get a helmet that fits the type of paddling you will do – full face protection is nice for steep creeking but maybe not necessary for surf zone; brims on helmets are nice for keeping the sun out of your face on the ocean but the river currents can grab the brim and pull the helmet back. Don’t choose based on the price tag – make a smart choice that shows what is in your skull is worth protecting.
And after you have that shiny new helmet be prepared to buy another in the future: if you do ever take a big hit and are all happy because your helmet absorbed the blow that is the time to retire it and get a new one. Even multiple impact helmets have their limit and you can’t always see when you’ve gone past that point. An old helmet is always suspect.