Head protection replacement information

The post on hardhat safety gave me inspiration to look into what the guidelines were for other forms of head protection used more recreationally.  The first thing I looked for was the Snell guidelines which cover many different kinds of helmets including motorcycles, bicycles, skateboards and skiing which I will add some data for.  The assumption here is that the helmet, and more importantly, its owner have not been in any major crash.  The general guideline Snell gives is every 5 years:

Why replace every 5 years.

From that point, I wanted to look to see if there was much in the way of disagreement in terms of suggesting greater frequency of replacement.  I didn't see much for motorcycle helmets needing to be replaced more often than 5 years (This also covers helmets for race cars from go-carts and up).  I did find some more conservative estimates for others.

Bicycle Helmet:  It does range from 3-5 years.  For what it is worth, most of the 3 year recommendations come from manufacturers.

When to replace your bike helmet

Skateboard Helmet:  Very similar to bicycles in 3-5 years.  Here is an article with some guidelines:

When to replace your skate helmet.

Ski Helmet:  Again, the 3-5 year expectation remains.  Temperature extremes have been noted with other helmet types, but there is a certain expectation it might be even greater with skiing.

When to replace your ski helmet

Horseback Riding Helmet: As long as I was out looking, I found the same 5 year rule.

When should you replace your riding helmet

The common thread here is that these are activities is that you wear a helmet hoping it never gets used.  Contact sports like football and hockey have very different requirements and I didn't go looking except to know that there is material out there.

Additionally, here is some material on helmet inspection and care.

Bicycle Specific Helmet Inspection

More generic helmet inspection

Motorcycle helmet care tips