[Fred Wilson]

Do you regularly do a thorough Helmet Inspection? Yes / No.

Helmets made before 1984 just did not have the protection of helmets when the 1984 ANSI standard swept the junk off the market.

"You must replace a helmet after any crash where your head hit.
The foam part of a helmet is made for one-time use, and after crushing once it is no longer as protective as it was, even if it still looks intact.
Bear in mind that if the helmet did its job most people would tell you that they did not even hit their head, or did not hit their head that hard.
And the thin shells on most helmets now tend to hide any dents in the foam.
But if you can see marks on the shell or measure any foam crush at all, replace the helmet.
(Helmets made of EPP foam do recover, but there are few EPP helmets on the market. Yours is EPS or EPU unless otherwise labeled.)

You can also crack the helmet foam or damage it by dropping the helmet on a hard surface.
The cracks may be small and hard to see, so you need to look carefully. Cracks in the foam always require replacement of the helmet.

You may be reluctant to replace a helmet that looks almost as good as new, but if you did hit, you don't want to take chances on where you will hit next time.
If the foam is cracked under the thin shell, it will be more likely to fly apart in your next crash."

The Italian company MET says in their 2010 catalog:

"We are often asked 'For how long is a helmet safe?', or 'how often should I replace my helmet?
Until now it has been difficult to find any reliable figures to help answer these queries.
MET have now developed a series of tests which are conducted on aged helmets to determine a
'best before' date (unless the helmet is involved in an accident. In that case it should be replaced immediately.)
The results indicate 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.

MET's (Bicycle) Helmet Inspection Check List - is an appropriate guideline for any helmet.

[Fred Wilson]

CIVL did an extensive study on the topic of helmets and selected EN966 certified helmets.
These have been been mandatory in Cat 1 events since 1 January 2010.

See CIVL's list of approved helmets:
http://www.fai.org/civl-our-sport/safety/161-civl/31641-helmets-for-airsports