New helmet manufactured date?

[fmradio516]

I just bought a new Kask and the manuf date on the inside of the helmet is 11/2018. Is this normal? Or am I getting a stores "bottom of the pile" that is already almost a year old? Bought it from BikeTiresDirect.com, which I think is a safe bet.

It wasnt cheap and i know some people say you should go by that date when talking about your helmets lifespan.

[Mark McM]

Originally Posted by fmradio516

I just bought a new Kask and the manuf date on the inside of the helmet is 11/2018. Is this normal? Or am I getting a stores "bottom of the pile" that is already almost a year old? Bought it from BikeTiresDirect.com, which I think is a safe bet.

It wasnt cheap and i know some people say you should go by that date when talking about your helmets lifespan.

That's probably not unusual. These are likely manufactured in a large batch in southeast Asia, then shipped out in containers by slow boat to the US were they are placed in a warehouse. There they sits waiting to be ordered by and shipped out to a distributor, who places it in his own warehouse, to sit until they receive an order from a retailer. It then sits on a retailers shelf until purchased by a customer.

I would not be at all surprised if each model of helmet is produced only once or twice a year, based on pre-orders and anticipated sales volumes. While this may be changing, in the past this was the typical model for seasonal products (such as sporting goods).

As far as helmet life spans - there's no hard and fast answer on how often to replace a helmet. Definitely replace it after being in an accident, but other than that, there are far too many variables to account for (temperature, sunlight, exposure to harsh chemicals, etc.). In general, age alone is not enough to degrade helmets. Recommendations to replace a helmet at a specific time intervals are usually offered by people who benefit from frequent helmet sales (manufacturers, retailers, etc.). Here's an excerpt from the Bicycle Helmet Institutes page on helmet replacement:

Is it newer? With what standards sticker inside?
Newer helmets from the late 1980's and the 90's may or may not need replacement. First look to see what standards sticker is inside. If it's ASTM or Snell, the helmet was designed to meet today's standards for impact protection, and you may even find that Consumer Reports tested it in one of their articles. Most manufacturers now recommend that helmets be replaced after five years, but some of that may be just marketing. (Bell now recommends every three years, which seems to us too short. They base it partially on updating your helmet technology, but we would take that with a grain of salt.) Deterioration depends on usage, care, and abuse. We have seen helmet shells deteriorate from constant exposure to sunlight. So if you ride thousands of miles every year, five years may be a realistic estimate of helmet life. And helmets have actually been improving enough over time to make it a reasonable bet that you can find a better one than you did five years ago. It may fit better, look better, and in some cases may even be more protective. For an alternate view that agrees with the manufacturers, check out the helmet FAQ of the Snell Foundation. Snell knows a lot about helmets and their views on this subject should not be dismissed lightly, even though we disagree with them.

Occasionally somebody spreads rumors that sweat and ultraviolet (UV) exposure will cause your helmet to degrade. Sweat will not do that. The standards do not permit manufacturers to make a helmet that degrades from sweat, and the EPS, EPP or EPU foam is remarkably unaffected by salt water. Your helmet will get a terminal case of grunge before it dies of sweat. Sunlight can affect the strength of the shell material, though. Since helmets spend a lot of time in the sun, manufacturers usually put UV inhibitors in the plastic for their shells that control UV degradation. If your helmet is fading or showing small cracks around the vents, the UV inhibitors may be failing, so you probably should replace it. Chances are it has seen an awful lot of sun to have that happen. Otherwise, try another brand next time and let us know what brand faded on you.

At least one shop told a customer that the EPS in his three year old helmet was now "dried out." Other sales people refer to "outgassing" and say that the foam loses gas and impact performance is affected. Still others claim that helmets lose a percentage of their effectiveness each year, with the percentage growing with age. All of that is nothing but marketing hype to sell a replacement helmet before you need it. There is some loss of aromatics in the first hours and days after molding, and helmet designers take account of that for standards testing. But after that the foam stabilizes and does not change for many years, unless the EPS is placed in an oven for some period of time and baked. The interior of your car, for example, will not do that, based on helmets we have seen and at least one lab crash test of a helmet always kept in a car in Virginia over many summers. Helmet shells can be affected by car heat, but not the foam. The Snell Memorial Foundation has tested motorcycle helmets held in storage for more than 20 years and found that they still meet the original standard. See the next paragraph for lab testing of bicycle helmets showing the same thing.


Test Lab proof that performance holds up
In 2015 MEA Forensic reported on their extensive testing of used (but not crashed) bicycle helmets shows that the foam liners retain their performance over many years. Some of the helmets were as old as 26 years. They crash tested 675 helmets in their lab. Their analysis showed that there was no significant impact performance change with age. Their data including all 675 helmets tested produced only a 0.7g per year increase in impact readings at the higher drop height. After crash testing the helmets on a standard test rig, MEA took core samples from an uncrashed area of 63 helmets and tested them. This generated data based solely on the foam performance. Again, the findings indicate that helmet liner foam does not deteriorate with age. We have more on this landmark study in this Update newsletter.


Looking for an honest manufacturer
The Italian company MET said in their 2010 catalog that after conducting a test program they had found that "if used properly accordingly to our owner manual, our helmets will still do their job up to eight years after they have been made." Unfortunately they now say three to five years. Perhaps their helmets have changed.
We applauded MET at the time for undertaking an actual testing program on helmet life and for making that statement. We regarded it as a triumph of integrity over marketing. MET's helmets were made with industry standard shells and liners, so there is no reason we can see that their recommendation should not be good for many other helmet brands as well. If another manufacturer comes up with a testing program that shows earlier deterioration in the protection from their products we will revise this page. Most are now telling you that if your helmet does not have MIPS or some rotational energy technology you should replace it. We have a page up on that.

In sum, we don't find the case for replacing a helmet that meets the ASTM or Snell standards that compelling if the helmet is still in good shape and fits you well.