Re: Batch Testing
Regarding the batch testing issue, I was under the impression that if there was a failure the manufacturer would be able to resubmit samples to a third party testing agency and the ringers would come into play there. I could be completely incorrect about that and it would be some what questionable as to what would happen to the inventory in "holding" during testing. It would be possible for a manfuacturer slip those through to the marketplace. By no means am I accusing anybody of practicing such acts, but merely pointing out I was under the impression it is possible.
As mentioned before it is about the integrity and control procedures of manufacturers to help promote the production of a consistent product that can meet a minimum quality, performance, and saftey standard (whatever that may be).
There is some intrinsic mental hurdle I cannot clear regarding lower 2nd energy impacts. I have yet to see a trace of a helmet net a higher G reading that was designed for a higher impact energy that is tested at a lower energy than a helmet that was designed for a lower 2nd impact energy. That is, I have yet to see helmet A designed for a 110j 2nd drop have a significantly higher G reading than a helmet helmet B designed for a 70j when both helmets are tested at 70j. Maybe I haven't hit enough helmets.
Regarding the RST protocol to hit to a lower performance standard, it is only to confirm there is an issue with the helmet in question. As with any manufactured good, there is a tolerance in which every helmet will perform. Before crying wolf, they want to be absolutely sure tehre is something wrong with the helmet. If you're riding the hairy edge to pass a standard, it is no suprise that not every helmet you build will absolutely pass--your manfuacturing tolerance will not allow for this, depending on how hard your helmet is pushing the limit. This is no different than what TP-218-04a does for DOT. If there is another failure at the lower performance levels there IS something WRONG and some corrective action is pretty much mandatory.
As far as helmets that are 5 years old, as long as there have been no changes to the shell or liner, the should perform just as well as the first helmet that rolled off the assembly line from day 1. I would be hard pressed to find a difference between testing a helmet made 5 years ago straight off the line where the shell is made of the same fabric and resin and method, and the liner is made of the same material to the same specification that is found in a helmet made yesterday. What has changed? Take it to the umpteenth degree, take a helmet off the line, put it in STP conditions without exposure to light for 5 years in a N2 environment, then take the same hlemet off the line and hit both: if both were constructed using identical methods and materials, I would be very hard pressed to find a difference in performance.
As far as comparing standards, there is much running around in circles and the bottom line basically boils down to: it being up to the manufacturer to decide upon their own sampling procedure they are comfortable with (be it MIL Spec or QS9000 or what not) to ensure each lot of helmets leaving the factory can meet their minimum performance requirements. When DOT or a RST catches a failure, there is a definite issue at hand. BSI tries to prevent that by proactively implementing batch testing before manufacturers can release product into the field.
In terms of helmet peformance, you can't beat the laws of physics. Standards can be written and debated until the cows come home. When it comes to buying one as a consumer, it's mostly an issue of making sure hte helmet fits properly and at the very least meets some saftey standard that they are comfortable with or required by law, be it DOT, BSI or EN 22/05.... The rest of it, how much they spend is jsut a net result of how much personal utility they will recieve after making their purchase.
--
George
Regarding the batch testing issue, I was under the impression that if there was a failure the manufacturer would be able to resubmit samples to a third party testing agency and the ringers would come into play there. I could be completely incorrect about that and it would be some what questionable as to what would happen to the inventory in "holding" during testing. It would be possible for a manfuacturer slip those through to the marketplace. By no means am I accusing anybody of practicing such acts, but merely pointing out I was under the impression it is possible.
As mentioned before it is about the integrity and control procedures of manufacturers to help promote the production of a consistent product that can meet a minimum quality, performance, and saftey standard (whatever that may be).
There is some intrinsic mental hurdle I cannot clear regarding lower 2nd energy impacts. I have yet to see a trace of a helmet net a higher G reading that was designed for a higher impact energy that is tested at a lower energy than a helmet that was designed for a lower 2nd impact energy. That is, I have yet to see helmet A designed for a 110j 2nd drop have a significantly higher G reading than a helmet helmet B designed for a 70j when both helmets are tested at 70j. Maybe I haven't hit enough helmets.
Regarding the RST protocol to hit to a lower performance standard, it is only to confirm there is an issue with the helmet in question. As with any manufactured good, there is a tolerance in which every helmet will perform. Before crying wolf, they want to be absolutely sure tehre is something wrong with the helmet. If you're riding the hairy edge to pass a standard, it is no suprise that not every helmet you build will absolutely pass--your manfuacturing tolerance will not allow for this, depending on how hard your helmet is pushing the limit. This is no different than what TP-218-04a does for DOT. If there is another failure at the lower performance levels there IS something WRONG and some corrective action is pretty much mandatory.
As far as helmets that are 5 years old, as long as there have been no changes to the shell or liner, the should perform just as well as the first helmet that rolled off the assembly line from day 1. I would be hard pressed to find a difference between testing a helmet made 5 years ago straight off the line where the shell is made of the same fabric and resin and method, and the liner is made of the same material to the same specification that is found in a helmet made yesterday. What has changed? Take it to the umpteenth degree, take a helmet off the line, put it in STP conditions without exposure to light for 5 years in a N2 environment, then take the same hlemet off the line and hit both: if both were constructed using identical methods and materials, I would be very hard pressed to find a difference in performance.
As far as comparing standards, there is much running around in circles and the bottom line basically boils down to: it being up to the manufacturer to decide upon their own sampling procedure they are comfortable with (be it MIL Spec or QS9000 or what not) to ensure each lot of helmets leaving the factory can meet their minimum performance requirements. When DOT or a RST catches a failure, there is a definite issue at hand. BSI tries to prevent that by proactively implementing batch testing before manufacturers can release product into the field.
In terms of helmet peformance, you can't beat the laws of physics. Standards can be written and debated until the cows come home. When it comes to buying one as a consumer, it's mostly an issue of making sure hte helmet fits properly and at the very least meets some saftey standard that they are comfortable with or required by law, be it DOT, BSI or EN 22/05.... The rest of it, how much they spend is jsut a net result of how much personal utility they will recieve after making their purchase.
--
George
And, yes, I am looking into the tests mentioned above in this thread.
