M2010 and ECE R22-05 impact tests differ most in severity. Although the first M2010 impact at a site on the helmet is at a velocity of 7.75 m/sec, only slightly greater than 7.5 m/sec velocity in ECE R22-05, this difference is amplified by the choice of Impact test equipment. The “guided fall” equipment specified in M2010 is estimated to be as much as 20% more severe for equal velocities than the free drop device specified by ECE R22-05. And M2010 then demands a second impact at the same site looking for a substantial margin of impact management capability beyond what was exhausted in the first strike. Helmets without this margin or, for any reason unable to withstand multiple impacts cannot pass this test.
In addition to a flat impact surface, both standards call out aggressive impact surfaces which concentrate impact stresses in order to punch through a relatively small area of the helmet to the wearer’s head inside. A helmet must combine a rigid outer shell with a sufficient wall thickness in order to meet test requirements. However, ECE R22-05 substitutes a “kerbstone” surface for the “hemisphere” called out in M2010 and also in the United States DOT-FMVSS218 and BSI 6658-85. This kerbstone is better suited to free drop testing but is not nearly as aggressive as the hemisphere. Taken together, the differences between guided-fall and free drop testing, the double impacts and the more aggressive hemispherical anvil imply that M2010 impact testing is as much as 50% to 100% more severe than in ECE R22-05.

Note: Only single impacts are applied against the edge anvil in Snell M2010. This is a test of shell toughness generally conducted after the helmet has withstood four double impacts at four other sites against the either the flat or hemispherical anvils.

In addition to the aggressive hemispherical impact surface, M2010 also stresses helmet shells with the shell penetration test and with an “edge” impact surface. M2010 demands only a single impact against this edge at any particular site but the edge concentrates the loading along a narrow line much like an axe. The helmet shell must be particularly tough to avoid being split apart. M2010 also tests the shell with a conical point driven by 3 kilograms dropped through 3 meters. This same shell penetration also appears in the United States national requirement, DOT/FMVSS218, and in BSI 6658-1985. Both these tests demand shell toughness and demonstrate a measure of protection from edged and pointed hazards such as motorcycle foot pegs, road signage and roadside barrier structures.