helmet life

My first Arai helmet got severely gouged and scratched as I bounced down the road one day. ZERO doubt that helmet saved my life. Went through extensive mental wrangling before making decision to ride again. We'll leave my wife's feelings about that decision out of this post. There were no...

As a general rule we are all told to change our standard fiber glass / composite helmets every 5 years, however carbon fiber does not break down like standard composite helmets. So what is an acceptable lifespan for a carbon fiber helmet? Until the interior no longer fits or is there a better gauge?

My wife bought a Schuberth C3w. We thought that we were buying a Schuberth C3pro woman and wanted to swap the SRC-System from my C3 Pro. It can not be done. We are exchanging it. While trying to I found the manufacture date of 9/2011. Is it common for helmets to set in a warehouse for 3 years...