I am curious if anyone uses a skiing helmet for winter biking? Would this be safe? Are skiing helmets designed to protect you from the same kind of accidents that you would have on a bike?
My thinking is that a ski helmet would:
I wear a Bern Brentwood with a winter liner in cold weather. It's a certified bike helmet, but designed more like a ski helmet. The winter liner does a great job of keeping my ears warm without wearing any other protection, but doesn't block traffic noise. It is vented, but not well enough that it makes my head cold. It also has a clip in the back for ski goggles if you're using them. With the summer liner it works well for fall and spring, too.
As mentioned in this answer to another question, I commute all winter in central Vermont with a Giro 9 ski helmet and goggles. The winter weather here has lots of sleet and snow with temperatures mostly in the 5 °F–20 °F (–15 °C to –6 °C) range with sub-zero temps at times.
This Giro helmet [and apparently many recent ski helmets] conform to the ASTM 2040 safety standard. This helmet has very similar construction to my Giro bike helmet (primarily dense foam with a thin plastic shell).
According to this site ASTM 2040 is almost identical to the Consumer Product Safety Council's (CPSC) standard for bicycle helmets, but with additions for mandatory low-temperature performance. Compare the ASTM description to this description of CPSC testing. Both standards require 4 drop tests from two meters height: two onto flat anvils, one onto a hemispherical anvil, and one onto an angled edge anvil. In both standards, the helmet fails if the instrumented head-form exceeds 300 g's on impact. Both standards require testing of chin-straps and roll-off.
Given that the speeds and obstacles (automobiles aside) are very similar skiing and biking, I feel very comfortable wearing the Giro 9 while biking. The construction of this helmet is almost identical to that of my Giro bike helmet (the same gray foam with a thin outer shell), but with a significantly higher foam/hole ratio. As mentioned by freiheit, Giro markets one of its helmets for both downhill skiing and downhill mountain biking.
One nice feature about this particular ski helmet is that it has quite a bit of ventilation via removable rubber plugs in the openings on top. Since we generate a lot more heat biking than downhill skiing, this extra airflow keeps the head comfortable while the eyes and face are protected by goggles.
If you are commuting or riding after dark, be sure to get goggles that aren't too dark. Often clear or colored lenses are available that let through 90% or more of the available light and will let you see the road with your headlights.
Are skiing helmets designed to protect you from the same kind of acidents that you would have on a bike?
Here is an article, for what it's worth, about the kind[s] of accidents that skiing helmets are designed to protect you from: The Science Behind Helmets ... in summary:
My colleagues and I are strong believers in helmets and encourage everyone to use one. On the other hand, we are equally strong believers in the notion that helmets are not panaceas, and have an extremely limited ability to prevent serious head injuries. ... most snowsports fatalities due to head impact with solid fixed objects such as a tree take place at speeds of 44 kph or more ... only about 2.6 per cent of all medically significant injuries are what we call a potentially serious head injury (PSHI): a diagnosed skull fracture, concussion, closed head injury or traumatic brain injury (TBI). . This is in contrast to the broad defi nition of a head injury as “any injury above the neck,” which includes minor injuries such as scalp lacerations and the like. ... Kinetic energy goes up as the square of the velocity ... If those hard, cold facts are kept in mind, it’s easier to see and understand why helmets are fairly effective at preventing minor head injuries such as scalp lacerations, but not so good at preventing the more serious forms of head injury, especially fatalities due to direct impact with fixed objects. The public expects far more than a helmet could ever be expected to deliver. ... Our research and the research of others has consistently shown a 35- to 50-per-cent reduction in head injury if a head injury is defined as “any injury above the neck.” Helmets prevent close to 100 per cent of relatively minor head injuries (lacerations), but are far less effective at preventing serious head injury (concussions, closed head injury, subdural haematoma and so on). ... We believe that the kinetic energy in many death scenarios may be so massive as to overwhelm the degree of protection that any helmet could offer. Many fatalities appear to occur under circumstances that are likely to exceed the protective capacity of current helmets designed for recreational snowsports.
On another (but related) subject, according to the web sites referenced in this answer there is even, apparently, some controversy over whether bicycle helmets will protect you from the kind of accidents that you would have on a bike.
What I do when it's cold, in addition to wearing a skullcap or balaclava, is use clear packing tape to cover the front vents in my helmet. This has usually been sufficient for comfort during my 60-75 min commute in Utah winters down to 15-20 F.
Really a comment to "I want proper data" but it was too long.
There is no data that a ski helmet is safe for biking simply because there is no data that a bike helmet is safe for biking!
What you do have is an assumption that if a bike helmet contains a certain thickness of an impact absorbing material and a ski helmet contains an equal or greater thickness than it will have the same impact absorbing effect.
Similarly if bike helmets are required to survive a certain drop test impact and ski helmets are tested to an equal or greater impact then they are presumed to be equally safe.
There are extra features that may make a bike helmet more or less safe - it may be more vunerable to splitting along vents yet may have a smoother surface to reduce snag risk - some of these may be included in the testing, some may not.
And finally remember that the 'testing' isn't anything like as scientific as you might think. As described above it's normally just a anvil impact test.
Alternatively the standards may just specify a certain thickness of a material. Whenever you see a size quoted in a safety standard you have to be slightly suspicious of the science which discovered something had to be exactly 25.4mm thick to be safe!
If you're thinking about wearing a ski helmet for biking, for what it's worth the Snell RS-98 recreational skiing and B-95 biking helmet standards are nearly identical, word for word, including things like visibility requirements and anatomical coverage. There are some small differences in the drop test. The energy of the flat anvil drop test in the B-95 standard is 110J vs. 100J for the RS-98 ski standard. The hemispherical anvil drop test is 80 J for RS-98 and 72 for B-95. Bike helmets are tested against the point of a right angle "kerbstone" anvil, but ski helmets are tested against an "edge anvil" 6.3mm wide -- basically a decapitating machine -- and at higher forces than the kerbstone test too. Both bike and ski helmets have to be tested after being chilled and soaked, but bike helmets have to be tested after being cooked at 50 C (122 F).
The reasonable conclusion is that a Snell certified ski helmet is probably a suitable choice for winter biking, but should not be used after exposure to extreme heat. Yes, a certified ski helmet might pass the 100J flat anvil test but not the 110 J test, but it probably does.
As for ASTM 2040, who can say? It's not available for free inspection. But it appears that the requirements for recreational ski helmets and bike helmets are pretty close.
While a bike helmet may be better suited for crashing on a very hard surface (tarmac, concrete), skiing helmets are presumably well suited to handling an impact against the vertical things skiers hit (trees, lift poles). In that respect, a ski helmet might not be as good as a bike helmet but it ought to provide an acceptable level of protection.
One question that it brings up in my mind is how stringent the industry testing is for bicycle helmets compared to ski helmets. Helmets for biking have a lot of well-respected standards that they must comply to, from government groups like the Consumer Product Safety Commission in the US, to independent labs like Snell. Ski helmets haven't been around for nearly as long in wide usage, so I'd be wary of their technical efficacy. If you are going to use a ski helmet on a bike, be sure it at least has some independent certification.
I did once wear ski goggles whilst cycling through the snow, and felt that it probably was a bit less safe, because they cut down my peripheral vison a bit.
When It's pretty cold I normally wear a balaclava underneath my helmet, which I recommend heartily. It keeps the ears and face nice and warm.
Two really harsh winters with my Pro-Tec B2 Snow + transparent Peltor Virtua glasses , and I couldn't be more comfortable :-)
I just clicked on the "submit your order" button, and hopefully am receiving a POC Receptor Bug in the next few days. The security of that helmet i supposed to be very good, and I finally found one on sale (599:- SEK incl. p&p).
POC also makes a helmet that is both snow and bike
In the rain I use a bern with hard bill to help keep the water off my face
First off wearing a ski helmet is a lot better than wearing a wooly hat and scarf.
I've collected a fair amount of helmets over the years, from cheap £5 to snowboard and paintball helmets and used them while riding my bike.
During the autumn-winter months I tend to wear a bandanna under my cycle helmets. Come winter it's on with the snowboarding hi-viz gear. I live in Scotland where temps can hit -25 degrees easily.
The bottom line is stay safe. If you feel you get enough protection from the helmet go for it. Add up the pros and cons; it's your neck on the line, literally.
Here's a tip. If you walked into a winter sports shop the guy behind the counter would sell you a snowboarding helmet for cycling but a bike shop would say its not safe and guide you towards their brands.
It has been long enough since this question was originally asked for helmets to have adapted. Currently there is a model of bicycle helmet that is full face, and used for downhill bicycle racing. Most (if not all) of these are certified according to the ASTM F1952 standard, which is a more rigorous standard than the CPSC (Consumer Products Safety Commission), which is a US based safety certification that all recommended bicycle helmets are required to have in the US (I believe foreign models sold in the US must either meet or exceed CPSC standards).
The models will also list what standards they conform to, such as the list on the Bell Transfer helmet page.
If you look at current models such as the ones at Chain Reaction Cycles (Warning, link may decay), they are full face such as ski racing and motorcycle, and will accommodate goggles such as ski goggles. Add a head covering such as a balaclava or similar and you should be fine.
