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B90TT and B95TT: Addendum to B90A and B95A Standards for Protective Headgear for Use in Bicycling

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This addendum to the Snell Memorial Foundation Standards for adult bicycling helmets applies to headgear used in competition time trial racing, velodrome racing and comparable events.  These helmets are frequently configured with aerodynamic features like long, tapered tails which are calculated to reduce wind resistance and enable better racing performance.  However, these same features may be deemed inappropriate for bicycle helmets intended for street use and for casual riding.  In particular, long, tapered tails are considered to be projections which may become loading points for tangential forces and, as such, are in conflict with the sections of the standards concerning general limitations on construction.  However, there are no reasonable concerns for helmets used by experienced riders in supervised training or competition under controlled conditions.


This addendum waives the limitations on projections for aerodynamic tails and other reasonable, aerodynamic features for helmets to be used in well supervised time trial, velodrome and other comparable competition or training.  This addendum applies only to helmets meeting all other requirements of the Foundation’s 1995 or 1990 Standards for Protective Headgear for Use in Bicycling as prescribed for helmets intended for persons five years of age and older.


In order to be considered for certification, six identical samples of the helmet must be submitted.  They must meet the limitations on construction as modified by this addendum.  Five of the samples will be subjected to performance testing and must meet all those requirements as well.  If the headgear meets all requirements and is accepted into the Snell programs, production units must meet all the labeling requirements of the modified standard including one of the Foundation’s serialized certification labels either to B90TT or B95TT as appropriate. 


It must also include a durable, visible, and legible label worded to the following effect in English or in a language common to the area in which the helmet is to be distributed:


WARNING: THIS HELMET IS NOT INTENDED FOR RECREATIONAL USE. This special use helmet has been designed to provide an aerodynamic benefit through an aerodynamic tail which in a fall or crash may reduce its ability to provide adequate protection. In a fall or crash the aerodynamic tail may cause the helmet to be pushed out of position thereby exposing the head to serious and/or fatal injury. Similarly, in a fall or crash a rider may be exposed to a strangulation and/or choking hazard from the retention system. USE ONLY ON A CLOSED DESIGNATED COURSE IN CONNECTION WITH SANCTIONED TIME TRIALING ACTIVITIES OR COMPETITIVE EVENTS.