Some thoughts on helmet life

[Bill_Anderson]

We have all probably heard the axiom that we should replace our helmets every 4-5 years because the styrofoam-like material inside the helmet which absorbs and distributes energy upon impact deteriorates and loses this ability over time. Until recently I have heard two theories as to why this happens: 1) the material breaks down from exposure to sunlight, specifically UV rays and 2) the material breaks down from exposure to sweat and oil from the rider's head. With the exception of a helmet which has been exposed to direct sunlight while sitting on a display shelf, deterioration would not start in either case until the helmet was removed from its box and worn.

I recently heard a new (to me) theory about helmet deterioration: the styrofoam-like material emits gasses (out-gassing), which over time causes the material to dry out and become very brittle, much like an old styrofoam cooler. Once brittle, the material loses its ability to absorb and distribute impact energy. In this case, it seems to me that deterioration would start as soon as the helmet is produced, regardless of when it is sold and removed from the box for use.

If deterioration does begin upon manufacture through out-gassing, then should helmets be sold with a "replace by" date clearly marked on the helmet? Under the out-gassing theory, a name brand, quality, helmet may not offer its purchaser the degree of protection he thinks it will if it has been sitting unsold in a store room or display shelf for a long peroid of time before purchase.

Any thoughts on the validity of any of the deterioration theories and/or marking helmets with a replacement date?

[mrmuddy]

From a consumer perspective .I like the idea.!

However, if there was something to these theories .. My guess is that the lawyers would have jumped upon this years ago,,

[fixcinater]

They still sell half-helmets...

[Chuckracer]

I honestly don't worry about it. My current Arai is ten years old. I think it will do fine in a crash, besides, there are so many ways to die in a motorcycle accident, and head injury's are just one of them.

[Mike]

Originally Posted by Bill_Anderson

Any thoughts on the validity of any of the deterioration theories and/or marking helmets with a replacement date?

I'm sure the desirable qualities of the styrofoam do decline with age, the question is, how much and how fast? And on this we can only speculate but certainly it will be accelerated by temperature and UV rays, probably also by ozone and maybe other pollutants.

I have a white helmet which I think lasts longer than a black helmet due to it's lower shell temperature when in the sun. Because the energy absorbing material is attached to the shell I think this is a big factor. Helmets, new in the box and stored under cool temperatures, probably deteriorate very slowly. I bet most helmets that passed the DOT tests new would still pass 5-10 years later if they had been stored in the box (and associated plastic bags) and not subjected to higher temperatures.

In use I think helmets deteriorate more rapidly. My wild ass guess says they should be replaced after 4-10 years of use but it probably varies widely based upon particulars.

I like the new BMW Sportintegral but, because it's not DOT approved, it's really difficult to find one here in the U.S. to try on for size and fit is probably the single most important thing when it comes to the ability of the helmet to protect. At over $1500 I'm not too anxious to buy one just to see if it fits. Plus, it doesn't come in white which I think is useful from a safety (visibility) standpoint (as well as longevity as mentioned above).

The bottom line is if you want a new helmet you can always justify it with the deterioration argument and if you are happy with the helmet you have you can justify keeping it considering the lack of solid information on the subject.

[Purspeed]

I think that new Arai's do have the date of manufactured stamped somewhere (correct me if I am wrong).

Helmet technology advances dramatically, almost like computers. It may be a good idea to buy a new helmet every 4-5 years just to get the latest and greatest. And if you're American, then you don't have a choice, you've got to get the latest and greatest!

[Bill_Anderson]

Originally Posted by Purspeed

I think that new Arai's do have the date of manufactured stamped somewhere (correct me if I am wrong).

When I was at Ducati Seattle recently, one of the salesmen looked inside my helmet and said it was manufactured in 2001. I don't know where he found that date stamp. I did not purchase the helmet until 2003, which prompted my thoughts about helmets aging in the box or on the display shelf.

[Purspeed]

Originally Posted by Bill_Anderson

When I was at Ducati Seattle recently, one of the salesmen looked inside my helmet and said it was manufactured in 2001. I don't know where he found that date stamp. I did not purchase the helmet until 2003, which prompted my thoughts about helmets aging in the box or on the display shelf.

I had a similar concern when shopping for helmets. My strategy is to try and find a newly released color or model that did not exist in the preceding year. This way it has to be at most X months old.

New technology is certainly a reason to purchase a fresh lid; however, it would be interesting to find scientific proof regarding composition breakdown on helmets or helmet shelf life. You have to be asking yourself if the 4-5 year timeframe is a marketing gimmick or true science.

Now if Tempurpedic could supply their foam to helmets, that would be something...

[Bill_Anderson]

Originally Posted by Purspeed

Now if Tempurpedic could supply their foam to helmets, that would be something...

A buddy of mine was a pilot in the US Air Force. Their flight helmets are custom fitted to their heads by use of a foam mold. I know something similar was tried in ski boots many years ago. Your foot was stuck into a mold in which foam was injected. The foam hardened around your foot and was placed inside a hard plastic shell which formed the outer boot.

I have wondered if this technology could be economically adapted to motorcycle helmets to make individually fitted helmets with no hot spots.

[Purspeed]

Originally Posted by Bill_Anderson

A buddy of mine was a pilot in the US Air Force. Their flight helmets are custom fitted to their heads by use of a foam mold. I know something similar was tried in ski boots many years ago. Your foot was stuck into a mold in which foam was injected. The foam hardened around your foot and was placed inside a hard plastic shell which formed the outer boot.

I have wondered if this technology could be economically adapted to motorcycle helmets to make individually fitted helmets with no hot spots.

You can't get a better fit than that.

If it's good enough for military flight helmets, it should be good enough for our purposes. It would be interesting to see if this technology will filter down to us with a pricepoint that the market can bare.

I have custom earplugs that were injection molded and they're great.