Here's a document outlining safety standards for bicycle helmets sold in the United States: http://www.cpsc.gov//PageFiles/86318/10mr98r.pdf http://www.cpsc.gov

Here's a document outlining safety standards for bicycle helmets sold in the United States: http://www.cpsc.gov//PageFiles/86318/10mr98r.pdf http://www.cpsc.gov//PageFiles/86318/10mr98r.pdf As you can see, it's fairly rigorous. The main criticism is that by setting strict rules it discourages innovation. But that doesn't mean there are no decent standards or crash tests.