The problem of shock or friction sensitivity when dry applies mostly to picric acid powder, and that is something that is best kept a bit mushy physically. Perchlorate salts, particularly groups one and two metal ions, are produced and sold as anhydrous solids and are merely oxidizers (check DOT). The ammonium salt is another story though.
The first reference in Tilak's reply is an article on perchlorate salt hydrate stability, hydrate vs. non-hydrate, not stability of perchlorate ion itself, and is probably from the research group that you are advising.
Hope this clears the subject somewhat.
I admit that I don’t know the actual conditions on Mars of which the researchers are trying to duplicate the atmosphere and conditions.
But as a seasoned safety professional, I would propose the following viewpoint.
An experiment will involve a dry perchlorate, that normally must be maintained wetted and subsequently exposed to UV over a broad range of temperatures, albeit at a much lower pressure to be safe and the perchlorate could become shock sensitive. (Question: What caused the greatest naval disaster in maritime history of the Great Lakes? See:
John could be right, the reaction could be very safe and no worries.
In my opinion and experience, you have to many unknowns and variables that may be hypothesized, but have never been tested, either singularly or in combination.
I follow the rule of thumb to always plan for the unexpected and be prepared (sorry, old Boy Scout). To do so, the consideration should include the potential energy generation for the minimum containment necessary for the growth chamber, to include blast potential. In the worst-case situation, this could be considered over-engineering at the forefront. Which is worse, over-protecting or dealing with the aftermath?
It would be nice to hear from a few professionals actively involved in the accident investigations to provide perspective, but they are probably not allowed, and for good reason.
But, a few worse-case examples to consider are the Challenger Space Shuttle, the mislabeling, handling, etc. of numerous BSL4 labs with extremely potent agents. Do I need to continue?
A long time ago, the military agency I retired from had us pre-prepare news releases to potential consequences (had to be vetted through lawyers of course), and it was an excellent learning experience.
Don’t allow anything to occur which you are not prepared for the worst possible consequences… and how you would be able to handle or address them.
Kind of gets back to the old boy-scout motto of “Be Prepared” in a new light doesn’t it?
There are too many variables in the situation described below to disregard the potential impacts of a negative news day.
My opinion only,
Bruce Van Scoy
Here is a very different question for the group.
One of our UF researchers at NASA is using dry samples of perchlorates under UV lights to simulate the perchlorates found in Mars soils by the remote sampling devices on the rovers.
He is concerned about flammability or explosions of the pure reagent grade perchlorate compounds. The “soils” mixture in the growth chamber will simulate the Mars atmosphere. It will be under UV irradiation at temperatures between -80 to +20 oC. The growth chamber is kept at a low pressure (7 mbar) versus Earth sea level pressure (1015 mbar), and it will be under a nearly pure CO2 atmosphere.
Any thoughts on if the low pressure and low oxygen atmosphere render the experiments safe? Any other thoughts?
As always- a grateful thank you any replies.
Coordinator for Clinical and Laboratory Safety Programs
Environmental Health and Safety
University of Florida
POB 112190 Bldg 179 Newell Dr.
Gainesville, Fl 32611-2190
“Just because you are in compliance doesn’t mean you are out of danger.” Mike Rowe “Deadliest Catch”
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