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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Artificial horizons and mercury
From: Peter Ifland
Date: 2003 Jul 18, 10:40 -0400
From: Peter Ifland
Date: 2003 Jul 18, 10:40 -0400
Thanks George, for pointing us to the very relevant site on the practical safety precautions in handling mercury. I'm going back to my experiences in the chemistry lab, both as a student and as a professional chemist. Yes, mercury can be handled safely given some simple precautions. The most likely hazard is from long-term. low-level inhalation of vapors. Spills, such as George described in the school's chemistry lab in an earlier post, are the most common source of exposure. Mercury, once spilled, is virtually impossible to get back into the flask and it seeks to hide in cracks and crevices. Here's what I do when using a mercury artificial horizon: 1. Work outside. Don't open the flask or attempt transfer from one container to another in your home or workshop. 2. Put a large, flat, glass container under the receptacle when transferring from the flask to the horizon and back to catch any spills. 3. Return the mercury to the flask when finished taking the shots. Don't leave the open horizon lying around, even with the glass tent over it. (This will also minimize oxidation and discoloration of the surface of the mercury.) 4. Avoid contact of mercury with your skin. 5. Don't worry about getting your nose close to the mercury for a few moments while taking a shot with the sextant. This is trivial exposure, if any. 6. Talk to your local garbage disposal operator about how to dispose of any unwanted mercury. Do not just throw it in the trash. If you follow these steps and you still come down with mercury poisoning, it's probably from exposure to the mercury in the amalgam in your tooth fillings! Hope this helps. Peter Ifland