I'm one of those chemists Bob mentioned. Over the years, I've come to realize there's a lot of truth in something I heard in college; there are no dangerous chemicals, only dangerous PROCEDURES. Hydrofluoric acid (note the spelling) or "HF" can be used safely. HF is the active ingredient of glass-etching pastes and creams. You don't want to use the liquid, since it's much harder to control. These creams and pastes have rather low concentrations, but even so you want to take precautions. You'll probably see these same safety instructions on the bottle..... Don't work alone. If (god forbid) you do have to be taken to the emergency room, make sure that the product literature that came with your etching kit goes with you. That way the doctors and nurses will know EXACTLY what they're dealing with. Use plenty of ventilation. This really means: take the project outside. Wear safety goggles that cover the sides of your eyes Don't touch the stuff. Use rubber gloves. Check the gloves for leaks first by blowing them up like balloons, but JUST A LITTLE bit inflated. Don't use two layers of gloves (friction between the two layers will damage the gloves) Buck