May 2000 Volume 22 Number 2
The April issue of ACTS FACTS ran a alarming article about hexanes. I've written about hexanes in the past, but it seems I was a little timid. In my defense, I haven't heard much negative about the solvent of late. It seems like it is still being widely used and recommended.
It is a really sad, but sobering story. Bill Bowerman, a cofounder of Nike® died at age 88. He made his fame and fortune by developing the waffle sole that revolutionized the athletic shoe industry. During the development of the sole, he experimented with a variety of different liquid rubbers using his wife's waffle iron to set the polymer. One of the adhesives contained hexanes, and the prolonged exposure permanently damaged his nervous system. For the rest of his life, from the early 1970's until his death, he walked with a limp and wore a leg brace. Monona finishes off the article with: "If you use solvents of any type, do not ignore symptoms of numbness, cramping, or weakness in the hands, feet, arms or legs. Ignoring these symptoms can lead to a disease that cannot be cured even if you are as rich as the founder of Nike®."
So, once again: hexanes and solutions containing them have no place in the conservation lab. Heptane works almost identically and is much safer. I mentioned before that the reason hexanes are so toxic is because the n-hexane isomer is modified into something really nasty in the human liver. I learned from the ACTS FACTS article that the solvent "hexanes" is 40-55% n-hexane. The TLVs for n-hexane is 50 ppm; heptane, 400 ppm; and the other hexane isomers are 500 ppm. The other thing I hadn't known is that the neurological damage caused by hexane exposure is unique and demonstrable by nerve biopsy. And, this has led to lawsuits filed (and won) over hexane exposure in the arts. It makes for interesting reading.
As has been stated repeatedly in this column for years, every conservator who works with chemicals should have access to or subscribe to: ACTS FACTS; Monona Rossol, Editor; 181 Thompson St., #23; New York, NY 10012. The price is incredibly reasonable, $15 per year for 12 issues.
I've been asking WAAC Newsletter readers for ideas for future Health and Safety columns. I've even had a few responses and suggestions. (Thanks, and keep those emails coming. Cards and letters are fine too, if you are e-challenged.)
One question troubled me. I was asked about who was covered by OSHA regulations. The conservator had been led to believe that they were not covered by the federal regulations because they were employed by a state agency. I have spent a lot of time pouring over OSHA regs in the last couple of months assisting with the AIC Health and Safety Committee's forthcoming Guide on Chemical Hygiene Plans. Believe me, everyone (except the actual business owners if they are not employees) is protected by OSHA. In the old days, state workers and federal employees were exempt from protection, but this hasn't been the case for years.
I found the question troubling because it means that the conservator was being given incorrect information about the right to a safe workplace. For the record: yes, there are state occupational health and safety programs, but they must be at least as stringent as OSHA. A state cannot "relax" an OSHA rule.
The topic of microwave radiation exposure (for both conservator and object) also came up as suggestions for a future column. I don't have a clue about objects and their response to microwave radiation, but I have been following the issue of EM radiation effects on human health and safety in the lay press for some time.
Let me confess right here, right now: I'm one of those obnoxious people who carry a cell phone pretty much everywhere.
There have been recent studies that there could be health effects caused by cell phones. I don't think anyone could claim that the studies are conclusive, but they certainly are credible. And when you think about it, perhaps holding a moderately powerful microwave generator right next to your brain isn't such a good idea.
If you have a relatively modern phone, the answer is simple. Buy a hands-free head set (typically about $30). Then you can join me as a member of the most recent urban blight: the jackass walking around talking to him/herself, hands gesturing wildly, looking like an outpatient from the psycho ward but for the little tell-tale wire dangling from one ear. [My personal recommendation is that you hold the phone a foot or so away from your head so everyone can see you are merely rude (talking on your phone in public) and not nuts.]
And now for something completely different; a couple of tips:
I found a plug-in GFI device at my local hardware store that can be plugged into any outlet. It cost less than $20.00. It is about the size of one of those ubiquitous wall transformers that every modern appliance seems to require. It plugs into one outlet (dropping down so as not to block access to the other outlet) and your power cord or extension cord plugs into it.
Everyone should know about GFI devices. That's Ground Fault Interrupt to you non-hardware-store-junkies. They are those annoying things at the plug end of hair dryers. And while they may be a nuisance on hair dryers, they are great to have around the conservation studio -- they prevent most forms of electrocution. Plus, the GFI is a really cool piece of technology.
GFI prevents a current from flowing between an electrical appliance and an external ground. It does this by measuring the current that flows through each of the two power wires separately and comparing them. If there is any difference, the flow of electricity is shut-off nearly instantly. This prevents you from getting shocked should you contact a live wire while standing in a puddle. (The electricity would flow from the appliance, through you, into the water and to ground.)
It is important to remember that a GFI offers no protection from a short between the two wires that deliver power. So putting you finger into a light socket on a GFI protected circuit will give you a jolt because the electricity will travel from the center contact, through your finger, and back into the side contact. For all the GFI knows, you are just another light bulb, however dim -- all the current that went out came back. (If you were also standing in a puddle, the GFI would shut off as some of the current would travel to ground.) (I'm actually more concerned about where all these puddles are coming from. The Editor.)
As a general matter of electrical safety, all outlets in the studio should be protected by GFIs. The easiest way to accomplish this is by replacing all of your electrical outlets with GFI receptacles. If you are on-site or can't switch the outlets, the plug-in GFI would be a nice addition to your collection of safety devices. And since it compares current on the two power supplying wires, the absence of a proper ground (the third wire in a three prong receptacle) does not affect its performance.
The other cool product is the VAP.R Gardtm, manufactured by Lab Safety Supply. It is an activated carbon sorbent that goes into your solvent cabinet to absorb those stray fumes that can emanate from even the tidiest solvent storage cabinet. How many times has this happened to you? "Gee, (your name here), your studio is really impressive, but you really should empty your used swab can more often." "That's not my used swabs that you smell, it is solvent odor from my solvent storage cabinet. I'm so ashamed." (You might check those puddles, as well.) Lisa Goldberg (AIC News editor and a member of the AIC Health and Safety Committee) mentioned this to me. It sounds really cool. I plan to order a pair ($49.30) with my next purchase. Available from Lab Safety Supply, part OA-20532. Note that the product is not listed in their "Safety Direct" catalog.Chris Stavroudis is a conservator in private practice
Timestamp: Thursday, 11-Dec-2008 13:02:36 PST
Retrieved: Saturday, 24-Feb-2018 06:07:46 GMT