Re: Helmets, S vs M

["James Moran" <bavarian@xxxxxxxxxxxxx>]

S-rated helmet are for Skiing and are _entirely inappropriate_ for
motorsports.  SA or M denote Special Application (appropriate for automobile
use) and Motorcycle.  Yes, SA rated helmets do have a fire resistant liner
(Nomex usually) while M rated helmets do not.  Also, SA rated helmets go
through an additional impact management test series consisting of three
impacts with a roll bar shaped mandrel.  Finally, M rated helmets are
required to have a larger field of vision.  Otherwise, the standards for SA
and M helmets are essentially the same.  However, manufacturers differ in
their approaches to making SA and M helmets.  Some use the same shell with
different interior, while others use completely different shells and
interiors.

It is highly unlikely that you'll find any -90 (SA-90 or M-90) helmets for
sale anymore.  The current standard is -95.  They are working on their 2000
standards right now.

Visit the Snell Memorial Foundation web site (http://www.smf.org) for more
information.  Standards specific to the M and SA ratings are at:
http://www.smf.org/standards/M95std.html
http://www.smf.org/standards/sa95std.html

Go to section E4 for the impact management tests.

Jim Moran
'88 M6


- -----Original Message-----
From: Michael, Don <DMichael@domain.elided>
To: 'bmw-digest@domain.elided' <bmw-digest@domain.elided>
Date: Friday, December 18, 1998 2:52 PM
Subject: Helmets, S vs M


A Snell SA-rated helmet has a nomex liner and is required for SCCA racing.
An S-rated helmet is Snell-approved, but without the nomex
<snip>
I don't know for sure, but I suspect an M-type helmet has a much less
stringent quality spec and is considered suitable to get by motorcycle
helmet laws in some states. M-type is not suitable for much else. They're
one small step (maybe) above a bicycle helmet.

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