[msandford]

> I pointed out that manufacturers are free to develop their own standards and provided evidence to that effect.

They can only develop their own standards in excess of what the CSPC already requires of them. And their standard already sets the bar very, very high. Too high to be useful to most people.

So while that statement isn't blatantly and grossly wrong, I would argue that it's not really correct either. A more honest statement might be "manufacturers are free to develop their own standards (so long as they also meet CSPC minimums) and provided evidence to that effect"

A large portion of the point of this debate is "are the CSPC minimums a good tradeoff" and so pointing out that people can do whatever they want in excess of the CSPC minimums isn't exactly great form.

[maxerickson]

You started here:

You've assumed constant foam density which I don't believe is a given. That's how all helmets are made right now, but nothing would prevent someone from making two separate pieces and bonding them together, except cost. And what's the incentive to increase cost (and thus price) unless you can use that to differentiate somehow?

I don't see how my beating the point (to death) that manufacturers can go ahead and do that is bad form. If you want it, go ahead and take the last word.

[msandford]

Yes manufacturers can do it. I agree 100%. The point is that they aren't able to get anything for it! The CSPC test has FALSELY COMMODITIZED bicycle helmets where all helmets are SEEN as having the same level of safety regardless of the truth. Which then makes it very tough to sell people on extra safety, because all helmets are supposed to be AT LEAST SAFE ENOUGH thanks to the test.

I'm not trying to get the last word here, I'm trying to actually convince you of something. I know I'm doing something wrong, but I can't tell what. To me it's incredibly obvious that this particular standard is causing undesirable outcomes in society. I'm doing my damnedest to try and convince you of that. I'm having no success whatsoever. Intuitively it must be my fault; only I can tell if you're getting the gist of what I'm trying to communicate. It would be folly for me to blame you for not understanding my bad explanation.

1. Helmets only help you when they crush or break or deform. If they don't do this, they haven't really protected you.

2. Helmets are very strong, this is so that they can survive a very bad, high energy accident. This is required as per CSPC.

3. EPS doesn't start to crush until you've exceeded its compressive strength. In helmets, this is dictated by the maximal impact that it has to withstand.

4. Lower than maximal impacts will cause very little of the helmet to get used, or perhaps none at all. That means that the helmet did little or nothing to keep the person safe.

5. Crash severity is probably distributed as 1/x or as Poission meaning that low energy events are far, far more frequent than high energy events. Probably by several orders of magnitude.

7. The false commoditization of helmets (due to the CSPC test) makes it very difficult to convince people that there is anything else even worth looking at for safety (since everything is definitely safe enough), and even if you can do so you still have to design your standard to be in excess of the CSPC standard.

8. This leads a great many people to suffer concussions where a better designed helmet might have prevented them, while still providing an excellent level of safety for truly severe events. It is entirely possible to make a helmet which wouldn't pass the CSPC test that can provide good protection against concussion and death at the same time.

[maxerickson]

I think the problem is that you are imputing a position I have not taken.

I'm not especially convinced that the density of foam used in current helmets is egregiously bad, but that's a little different than being opposed to regulators and industry taking steps to make better helmets (it perhaps makes me a bit blase on the issue, and I anyway tend to come off as irreverent, whether I intend to or not).

The conversation also shifted a bit here: https://news.ycombinator.com/item?id=9720536

and I didn't really come along for the ride. I see how dismissing the idea of CSPC fines might come across as argumentative, but I really don't think that is a risk (especially in the face of extant private standards), and it is a different issue than the good Samaritan and false commoditization statements you have followed up with.

[msandford]

They're all separate issues unless you want better outcomes from helmets in crashes. In that case, any one particular issue could change a bit and there are better odds that you'd see things start moving in the right direction.

The existence of private safety standards doesn't mean that you're somehow exempt from the Federal ones.

"There are safety standards for most types of helmets. Bicycle and motorcycle helmets must comply with mandatory federal safety standards." http://www.cpsc.gov/en/Safety-Education/Safety-Guides/Sports...

I think it's a complicated issue and that there are a number of factors whose confluence is very unfortunate for cycling helmets at the current time. I do agree that this isn't the issue of our time or something that has great influence on the nation. But I tend to get very disappointed when there are federal regulations that are well-intended but end up giving people a false sense of security.

From the Bicycling Magazine article:

"Thompson sees his challenge as story and price. He has to convince customers that a MIPS-equipped helmet is safer, despite the fact that all helmets pass the same safety test. "If the customer can't digest that message," he says, "you're adding a system that nobody will care about.""

http://gearfinder.bicycling.com/senseless/index.html

"Most helmet designers and marketers are avid cyclists. The entry hall at the Dome is jammed with staffers' bikes. They ­value their brains and those of their customers. But their customers—from top pros to weekenders—haven't been clamoring­ for safer helmets, and the unchanging CPSC standards helped to ensure they were never offered one. And the industry's independent safety experts have for years insisted­ that no helmet can reduce concussion risk. Repeated often enough, that becomes accepted wisdom.

When the MIPS system appeared, those experts dismissed it. "That's not doing anything except taking up space," Dave ­Halstead told me. "It's a wonderful solution for a problem that does not exist."

Randy Swart, the ASTM helmet subcommittee's co-vice chairman, said he found the MIPS data "just not compelling." He called MIPS "an unproven technology. I think it just adds complexity—and could add to the thickness of the helmets."

In some cases, these assumptions were not true. The MIPS system doesn't make helmets larger or heavier. The idea that the only safer helmet is a bigger helmet has been accepted for so long that it's become an ingrained assumption."