- SFSU hot-shop code of safe practices (John Leighton). Good practice for all hot shops.
There are several threats in the studio that require eye protection:
- Physical - penetration by glass fragments, of which there are many sources. The most likely is fast-moving fragments emitted by breaking cold glass that is being worked or hasn't been properly annealed (e.g., on the end of a cold pipe or punty, or in the trash bucket). The fix is simple: wear a pair of safety glasses; preferably ones with side shields.
- Optical - there are two main dangers: high levels of infrared radiation (IR) from the furnaces and glory hole; and excess brightness. (A few sources claim that ultraviolet (UV) radiation is a hazard, too.) If your eyes feel like sandpaper after a blowing session, you this is the most likely cause. The best fix is to wear glasses or clip-on lenses that absorb infrared and some fraction of visible light. Several people find that green welder's glasses (shade #2 or #3) do this well. Philips safety offers several variants, including plastic clip-opns (these will fade and need replacing every year or two); they are available on Amazon.com.
Richard S. Lehman, Practical eye protection for glassworkers, 1998.
- For furnace work you want a gas welding type lens in shade 2.5 or 3. Lower (lighter) shades than this will not absorb enough IR to help much and anything higher than a shade 3 is going to be pretty dark.
- What you definitely DON'T want to wear are sunglasses or standard didymium glasses, neither of which absorb the infrared radiation encountered in a hotshop that can harm your eyes. Most sunglasses will actually do more harm than a clear lens by causing your pupil to open up because they are optically dark but then letting in all of the IR anyway. So this way your eye gets even more IR exposure than you would with a plain. clear lens. In a hotshop, it's the IR that will mess up your eyes.
- Personally I use a shade 2.5 Aura AUR-99 lens in the hotshop, or sometimes standard 3.0 welding glasses. The 3.0's can be a little dark if the shop isn't well lit, but with good lighting, they provide a little bit more protection than the shade 2.5's. Overall, the Aura's are more comfortable and way better looking and they come with a lifetime warranty against defects and breakage, as long as not abused. They are what I wear 99% of the time, and if I ever need another pair they are what I will order.
- Final recommendation: If you are looking for dirt cheap and have very good lighting in your studio, go with a standard gas welding glasses with a 3.0 lens. If you want something better quality (and better looking) and not much more expensive, go with a pair of Aura's with the AUR-99 lens in shade 2.5.
Protective eyeware sources:
- Aura Visual Concepts - protective eyeware (owned by a glassworker, comprehensive selection, can be expensive)
- Envirosafetyproducts.com - low prices, Pyramex flip up bifocals
- Phillips Safety Products - more comprehensive protection, more expensive
- Safetyglassesusa.com - many styles, low prices
You do not want to inhale powdered glass or silica, unless you want to get silicosis (the thing that kills coal miners).
Fortunately, Public Glass doesn't melt its glass from batch (powdered silica plus a bunch of other noxious chemicals), so lung safety and protection is less of an issue than it used to be at the SFSU studio. Nonetheless, grinding glass can generate fine dist, which isn't good for the lungs, and fine-grained frit or powdered color is Bad Stuff, too. The following guidelines, although aimed primarily at batch, are still highly relevant.