Originally Posted by lurkingknight
read somewhere that z87.1 (minimum rating) is only rated for a single 1 J impact.
z87.1+ covers higher J and multiple impacts.
That's correct and it's in my safety glasses thread
Z87.1 is around 1J, design specifically to protect your face from light particles, sparks, dust, etc. *NOT* designed to stop exploding grinder disks, or exploding bench grinders.
Z87.1+ is around 3J, I had math'd it out simply when I made the thread.
HOWEVER, that's 3J on a steel ball of an unknown weight. So even though it's designed to take 3J of that, it could potentially take a greater impact from a BB due to the fact a BB deforms on impact.
The minimum test rating is not necessarily the minimum rating of the glasses either. They could very well be good to 6J, they're just not guaranteed at 6J.