I tested an old can of bear pepper spray, dated to expire in 2011, this afternoon. I've kept this can in my vehicle for the 2 legged bears, but thankfully never needed it.
My father and mother are leaving for a long camping trip into bear country, so I told them about this product. I thought it might be a good idea for them to bring it. I offered them my can, though didn't realize that it expired 6 years ago. Once I realized just how old this thing was, well...
So, my father and I took it out back, to see what this old bear spray could do...
Wow. The spray blasted out of the can with a big whoosh reaching out maybe 30-40 feet. It was high pressured, all pepper and power. Cock and balls, in a can. If you hit someone directly in the face with this product, you'd disable them from the attack, instantly. Any living thing would drop from this stuff.
6 years expired, and, would have saved my life if I needed it. I'll be replacing this shortly.
This is the product:
http://www.mace.com/mace-bear-pepper-spray