Are Hövding helmets safer than regular helmets?

Question

I would like to know if these very expensive helmets (about 500€) are actually better than regular ones. I'm sceptical about the claim that they are three times safer: if they are so much safer, why do they not seem to be being used by professionals? I cannot find any serious studies supporting these claims, so am wondering whether they are in fact substantiated.

Answer 1

That's the inflatable "airbag" helmet. It's main claim to fame is that it isn't really a helmet, but sits in a (dorky looking) collar around your neck until needed.

First off, I'm skeptical that the helmet could be tested to most bike helmet standards at all, since the test procedures would not be designed for such a helmet. So it's pretty much impossible to say if it "meets standards", much less is better than others. For helmet testing info smf.org/standards/b/b90astd (thanks to @Ken Hiatt)

Secondly, the trigger mechanism can't rely (as a car airbag does) on waiting until impact to activate. So it must trigger based on sudden movements of the head and upper body. The reliability of this is questionable. (Keep in mind that a substantial number of head injuries while cycling are due to simply falling off the bike -- the old "forgot to unclip" problem, eg.)

Third, given the iffy nature of the trigger mechanism, false triggering would seem likely, and having the helmet suddenly inflate in a critical situation could be extremely disorienting and lead to an accident that would not otherwise happen.

Answer 2

I know this is an old thread but I thought I'd answer it anyway! I own one of these but did a lot of reading around the subject of helmets before my purchase and even then I deliberated for over a year! During that time they released version 2 of their Hovding which is lighter and more comfortable (according to their website). The price has also dropped to £250. I figured a company that is updating its product is a good thing and finally bought it - I've been happy with it. If you use it as intended (i.e. urban cycling) it makes a lot of sense.

In terms of their claims, they are backed up by a reputable insurance company called Folksam that did their own testing. It is true that you cannot compare the Hovding to the traditional helmet drop test because it inflates prior to impact whereas a helmet can be placed on a dummy head. However, their main point is that traditional drop tests allow a large amount of impact to transfer to the wearer. The difference with the airbag is that it absorbs the impact so that 3 or 4 times less impact goes to the wearer. It also protects from all ngles whereas the helmet is only tested for the crown (very top). In reality, according to independent research I think it was the occiput that impacted most commonly (back of head). There are some 'real' world examples of the hovding collar inflating when stunt riders have purposefully set it off and it does seem to inflate and protect the head (and perhaps neck) as it should, but it also seems to hard to set it off accidentally - which I know is a worry when you first get the thing!

I have ridden with it for only a few days but doing things like tying laces, getting on and off bike, running up stairs with it (I have a folding bike) haven't caused any mishaps. As you probably know they did about 7 years of research before creating version 1 of the helmet and collected a library of normal and abnormal movements. The likelihood of a false activation is pretty slim unless you are doing something very unusual / outside of the usual movements a cyclist makes, and this includes bunny hops, stairs, harsh acceleration / braking.

I remember the same anxiety when cars introduced air bags and the same discussion, but they proved to be safe - and now you wouldn't be happy to have a car without air bags - perhaps one day it will be the same for cycle helmets?

Answer 3

I have recently been looking to replace my old helmet. In searching about the merits of MIPS, I stumbled upon this question. In my cursory overview of the newest literature on the topic I found the following article: Modeling and Optimization of Airbag Helmets for Preventing Head Injuries in Bicycling (2017). Effectively, the study finds that,

based on a correlation with previously reported head injury criterion (HIC) values in the literature, this airbag helmet design substantially reduces the risks of severe head injury up to 9 m/s.

While this is perhaps the most important take away, one should also note the following design constraint of helmets in general.

At a head impact velocity of 6.0 m/s, the current expanded polystyrene (EPS) foam helmet results in high HIC values, which signals both a high risk of concussion (>50%) and a high risk of severe injury (>50% skull fracture). Even ideal foams and airbags below a thickness of 8 cm still result in substantial risk of concussion (50%), thus necessitating larger helmet designs .

As stiff materials are required to prevent bottoming-out in severe accidents but soft materials are sub-optimal at lower accelerations, a design compromise is typically made as shown by the green curve, above. Inflatable airbag helmets, by contrast,

represent a practical method for increasing helmet thickness during an impact through inflation... and the research demonstrates that such designs can significantly curtail risk of concussions and severe injuries, reducing HIC scores 5-fold compared to standard EPS helmets.

However, as the head impact velocity increases, these airbag helmets have a higher risk of bottoming-out. Therefore, a careful optimization of initial pressure for a given accident scenario is required.

This shows that work needs to continue on actuating and controlling pressure within the airbag.

The Swedish company Folksam carried out its own research, finding that the

Hövding helmet performed almost three times better than all the other conventional helmets in terms of peak accelerations at oblique impact tests (48 vs. 175 g at 5.42 m/s impact speed) They also noted an average 60% decrease in rotational accelerations compared with conventional helmets.

TLDR

• More expensive than legacy EPS foam helmets
• Work still ongoing to actuate airbag more reliably (although already quite excellent)
• Work still ongoing to better control airbag pressure through realtime sensors (needed for higher speed/ more forceful impacts)
• Current airbag helmet generation likely not a good choice for crashes at speeds >9m/s such as attained by 45km/h ebikes
• For most bike use cases, airbag more effective than traditional helmet to significantly reduce severity of brain injury during both oblique and torsional/rotational impacts
• Airbag provides more comprehensive protection around head than typical designs

Answer 4

A major problem that has not been mentioned is that the Hövding might not deploy at the right time (before impact) in some scenarios.

Since the trigger mechanism requires a rapid change in acceleration, any impact without any prior change in acceleration will not deploy the airbag but AFTER the impact.

For instance, watching this video

we can see that the deployment occurs a few centimeters before hitting the ground. This is acceptable if nothing is between your head and the ground. Just today I suffered a similar accident like the one on the video, with the difference that after I pressed the brakes, there was a car in front the bike BEFORE the ground. Had I been wearing the Hövding, I would have hit the car with my bare head.

More on this: https://helmets.org/airbag.htm

All in all, the Hövding would be perfect if it could be combined with a regular foam helmet. Sadly, this is not possible for the Hovding since "The bicycle helmet will prevent Hövding’s airbag from developing properly over your head in the event of an accident.".

Answer 5

After my research I've concluded that there is evidence it will be a lot safer (for a typical casual cyclist) IF it will always be fully inflated before impact and if it will reliably deploy and if you're not going crazy fast. I thought this Hövding stuff was nonsense tbh, but having looked at the Folksram testing and seen the rads/s² figures I'm considering starting to wear a "helmet" for ubran use. None of the negative effects of a helmet, with superior positives, if it deploys and fully inflates (but even then, better than no helmet from that point of view).

There is an important distinction between "Head injuries" and "Life-changing head injuries".

The vast majority of the latter, for typical casual cyclists on pedal bikes, are the result of angular acceleration in rads/s², and larger effective head size typically increases this (though according to the Folksram tests, not for the Hövding, presumeably as this larger size does not actually help leverage the twisting of the head, due to its lack of rigidity), as does a greater coefficient of friction between the helmet surface and whatever surface you crash on.

For Hövding: https://www.researchgate.net/publication/281630668_Folksam's_Bicycle_Helmet_Test_2015_Helena_Stigson

Apparently shows 1.5krads/s² when other helmets are at 4.2krads/s² or greater around the X axis and similar results for Y. This is very interesting. However, I would like to see more data points and more angles (there aren't enough for standard helmets either).

Note also that although these results are mildly favourable for MIPS helmets and the best non Hövding is a MIPS, there are non MIPS ones in there which outperform some MIPS, and further evidence of hard-shell importance for standard helmets is given the two fold differences between the YAKKA with and without the hard cover, which dwarfs any of the tiny gains that MIPS has made over conventional hard shells. (i.e. MIPS seems to work but it's a tiny difference in its current implementation.)

It's unclear if they are actually REALLY any better in linear acceleration situations, sure there is this: https://news.stanford.edu/2016/10/03/stanford-researchers-show-air-bag-bike-helmets-promise/

But notice:

In the testing, the air bag helmet was pre-inflated and the researchers maximized the pressure of the air inside the helmet before each drop in order to get these results.

Without the maximum amount of air, the air bag helmet could bottom out, causing the head to hit the ground with much more force than if it were wearing a traditional foam helmet.

Note also that the Stanford study is, in essence, crap. They drop a dummy wearing the helmet on a metal plate from up to 2 meters high, legs pointing down... that doesn't effectively model any bike accident except maybe popping out of a quarter pipe, losing your bike and dropping to the ground... which countless people do with no helmet, in fact that is how many bmxers learn certain tricks because the chances of hurting yourself with no fore/aft left/right motion are so low. But it's a "standard test"

Answer 6

One aspect that hasn't been tackled yet is, assuming the airbag is saver, does it actually work when needed. See the email correspondence below:

ANSWER

I have been following your product for a while and got to try it on the other day. I have been reading up on the advantages and one thing left to easy my mind is to get some information about quality control so I can be sure that the particular unit I receive is going to work (as there is no way of testing it without breaking it).

Best regards,

RESPONSE

We have sold about 50,000 helmets so far, of which we have received less than 10 complaints that the helmet has not worked properly. We have also received 800 reports that the helmet has saved lives in an accident. Of course, we can never give 100% guarantees. Nor can the car manufacturer with their air bags either.

ANSWER

Thank you for the information. The number 50,000 doesn't help though with regards to my question about quality control. The other information is quite interesting though.

You say there have been less than 10 complaints about the helmet not working. Because that is unspecific let's assume it was 9. Further you say you have received 800 reports of the helmet working properly.

That means, 800 + 9 = 809 incidents. That further means 9/809 = 1.1 % failure rate.

Just for arguments sake that means, out of the 50,000 sold, 500 won't work. Do you do any quality control samples?

And what about compensation in case the helmet fails in case of a crash?

RESPONSE

Our production is carried out at our partner Nihon Plast. Nihon Plast is a well-known Japanese based company serving several larger Japanese car manufacturer with their services in airbag technology, plastic manufacturing and assembly of products. Our production is carried out according to strict and detailed instructions and control plans. These plans include inspection of material, processes as well as finished product. All products that delivers from the factory has passed all such inspections, self-tests and inspections before delivery.

Complaints from customers who consider the product not meeting their expectations is very important and valuable information for us in our continues work of improving our product and customer experience of it. But please note that it is very difficult for any product to meet all customers' expectations. For Hövding our focus at to provide a superior head protection in a situation where the risk of potential severe head injury is identified. Still, this might mean that a situation where a customers considered that the product should have deployed and inflated the airbag - it doesn't. In these cases our product has not considered the situation to be as critical as the cyclist did. As of today none of these situations has caused any sever injury to the head of the cyclist, but in several of these cases the customer was disappointed since they expected the product to deploy.

Answer 7

Its not a helmet. I know someone who fell and it failed to deploy. They suffered a Traumatic Brain Injury (TBI), spent 2 weeks in a coma, 6 months in hospital and will be impaired for life. Its not a helmet and should not be sold as one.

Answer 8

Bicycle helmets are all certified to the same standard, so I would be sceptical of claims that one is safer than another. With bicycle helmets, a higher price usually gets you helmet that:

1. Weighs less
2. Has better vents to keep your head cooler
3. Is more stylish (i.e., "looks pro")

As for the Hovding helmet specifically, it looks like the main selling point is that it sits around your neck while you are not actively colliding with something. Some people seem to think that conventional helmets look dorky and all helmets seem to give you "helmet hair" to one degree or another. So, I would say that this is again a case where you are paying to get a helmet that gives you more of categories 2 and 3 above.