To Expand on Alberec’s (Brian’s) comment regarding Argon. Argon is
not only heavier, but being inert, if you were to breathe it in the
only concern would be if it displaced all the oxygen. It is totally
nontoxic to humans.
What you do need to worry about is the fumes, not the argon. Capture
at source combined with ventilation is always the preferred method
for dealing with it.
Remember the dose makes the poison, even water or oxygen is
poisonous to you, if you consume too much in too short a period…
While Hydrogen cyanide takes a microscopic dose which can be absorbed
over a longer period of time and still kill you.
In regards to being poisoned and at the risk of getting too
technical the 3 interrelated variables are Absorption rate, Clearance
rate, Toxic dose. As long as your body can clear it faster than you
are absorbing it and your body levels stay below the toxic levels you
won’t be poisoned.
The other class is cancer causing materials. Again the exposure
limits are calculated using similar variables using Rats as a target
class, which means unless you are a lawyer the results may or may not
Remember when reading health precautions and MSDS sheets, that they
are written both for worst case conditions and with lawyers in mind.
For your edification here are a few links:
You will notice both are similar but not identical, this is all too
common in MSDS sheets.
http://encyclopedia.airliquide.com/sds/en/097A_AL_EN.pdf – Europe
What is interesting here is how 3 different safety and lawsuit
environments require different presentations and subtly different
spin on the data.
But again this is Oxygen something we breath every day… it can’t
be dangerous right?