Since March 10th of 1999, all bicycle helmets sold in the United States have been required to pass the CPSC helmet standard. Prior to that point, several popular helmet standards (ANSI, ASTM and Snell) floated about, each with substantially different testing regimens. In the United States, helmet manufacturers could choose to meet any, all, or none of those standards
All of this proved confusing to consumers.
Congress passed legislation in 1994 (the Children’s Bicycle Helmet Safety Act), calling for all cycling helmets to meet a single, national standard. Other cycling helmet standards still exist, but now U.S. consumers are guaranteed a common performance threshold with any bike helmet purchased in the United States.
The CPSC standard is largely based on the pre-existing ASTM 1447 standard (originally published in 1993). The primary difference between these two standards is that CPSC is mandatory, whereas ASTM 1447 had been voluntary.
A modern adaptation.
The CPSC standard strikes a common ground in bicycle helmet standards—it’s more demanding than the other most common standard (EN-1078), but somewhat less demanding than the Snell B-95 standard.
CPSC subjects helmets to higher energy hits than EN 1078 (and more of them) from greater heights on both the flat and curbstone anvils. Those impacts are also spaced more closely together than called for by EN 1078. What’s more, the CPSC standard requires that passing helmets withstand the hemi anvil test—EN 1078 does not.
On the other hand, CPSC is slightly less demanding than the Snell 95 standard, which exposes helmets to greater impact energies and requires a lower test line than the CPSC standard, thus emphasizing protection over a greater portion of the helmet. Not surprisingly, the CPSC standard is also less demanding than the ASTM F 1952 downhill mountain biking helmet standard, which is similar in many respects, but calls for greater impact energies and, if a chinbar is present, a chin bar deflection test.
While all helmets sold in the United States must meet this government standard, government agencies don’t actually test these helmets as part of the certification process. Instead, brands must submit eight helmets of any given model to a “reasonable testing program”. Testing can be conducted by either the helmet manufacturer or a third-party testing facility that strictly adheres to the to the CPSC standard test protocols. It’s been called, by some critics, certification via “the honor system”.
Per the CPSC standard, records of the test results must be kept on file for at least three years and made available to the Consumer Products Safety Commission within 48 hours of a request for verification. Violations of the standard can result in “recall, injunctions, seizure of the product, and civil or criminal penalties.”