Last November at the NEDiv SCCA mini convention, a friend of mine came to me with an issue. he'd acquired a Hutchins Device (one of the modern head & neck restraint systems) on ebay, and was concerned because the word "void" showed up on the certification stickers.
Stickers of this type have been around for around 12 years. they're designed so that when you peel them off, the word void appears. having the word void show up on a legitimate item which has not been tampered with would be a bit of a problem. discussion at the time suggested the problem was because the device was clear coated carbon fiber, and light was getting behind the stickers.
on Saturday, i went to Long Island to do annual inspections for a bunch of SCCA race cars, and of course got to inspect driver gear. since the restraint systems are mandatory this year, i saw a bunch of those too. what was interested was that all the new HANS devices were matte finish, no clear coat. they did not have problems with the FIA & SFI certification stickers. there was one older HANS, clear coated, and sure enough, the word VOID showed up.
we're going to have to do some training of tech inspectors on this. it's possible to tell if a sticker has been tampered with or not, you just need to think through it. when we peel off a helmet sticker, the material that fills the word void physically pulls away from the sticker. when the word void shows up on a clear coated HANS device, the shiny fill is not missing, you just see a thin outline around the word void. these latter stickers are fine.