>From the Snell site <http://www.smf.org/faqs.html#Q5> :
What are the differences between the SA and M standards?
SA Standard was designed for auto racing while M Standard was for
motorcycling and other motorsports. There are three major differences
SA standard requires flammability test while the M standard does not;
SA standard allows narrower visual field than M standard (Some SA
helmets may not be street legal);
SA standard has rollbar impact test while M standard does not.
[mailto:firstname.lastname@example.org] On Behalf Of Mark Palmer
Sent: Friday, November 09, 2001 3:15 PM
To: email@example.com; firstname.lastname@example.org
Subject: Re: Helmets
Check your specs. I have heard this story several times, but that last
I looked at the Snell specs, the SA and M specs were identical in terms
impact testing. Maybe it has changed, but as of '90 or '95 the only
difference was fire protection.
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