MORE INFORMATIONS for laser protective goggles:
1. for the T: some people do not know what the T mean, T here means transparency. for a special wavelength goggles, a T=30% means there are 30% laser can pass through. for a full wavelength goggles, T here means an average level. as you can see in the picture, when you use a 405nm laser for the goggles, there are about 30% can pass through. if you use a red/green laser, there is about 50% pass through. if we use a 1064nm on the goggles, it is about 20%. so that we get an average value for T=30%.
a customer of us said, a laser goggles should be T=0.01. if T here is 0.01, how you can see the laser beam path?this kind of goggles will block all laser light. you cannot see anything if you wear it. 
2. for CE certificate, a customer of us said he need a CE certificated goggles for IPL, I recommended this one, but he doubts the CE mark and said that everyone can mark the CE logo on it. for this experience, I do not know how to reply his message, if you doubt the CE certificate, please do not buy it. we have goggles without CE mark, the price is much more cheaper. so that it is meaningless for us to mark something if we do not have it.
3. for the OD: OD means obviouse density. normally the higher OD the goggles is the better protective effect it can be. so that we normaly get OD4+, for red laser goggles, we also have OD6+.