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Keith Hughes
 
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Default Air compressor for hull cleaning

Richard J Kinch wrote:
MMC writes:


The toxins are minute until the compressor pistons rings get worn (or
do not fit right from the beginning) and allow oil to enter the
cylinders. With the heat that's generated by compressing air, the oil
will partially burn and create carbon monoxide which coats the red
blood cells and prohibits the transfer of oxygen to those cells and
further to the other cells in the body.



You are confusing heat and temperature, because compressing air does not
generate heat.


Nonsense. The "compression of air", i.e. the volume change alone, does
not change heat content(enthalpy), however mechanically "compressing
air" always does. Any mechanism that compresses air does work on the
system (consider all the frictional components), and that work is
reflected in increased temperature and enthalpy.

The existing heat is concentrated into a smaller volume,
raising the temperature, but this does not rise to ignition at 90 psi.


Ignition temperatures are not required, however, to generate volatilized
oxidation components. CO is not likely to be an issue without
ignition-high temps, but I'd just as soon not breath contaminated oil vapor.

Perhaps you are thinking of scuba tank compressors at many 1000s of psi.

If what you say were true, then working with compressed air in a closed
shop would be even more hazardous, since the air is recycled over and
over through the compressor as it is exhausted into the room. But there
is no CO or oil vapor to be concerned with in those situations.


Hardly the same context given the dilutional differences. A "closed"
shop is *not* a sealed shop.

Mineral oil is not toxic in itself.


In the gut, no. In the lungs, yes. Coat your alveoli with it and see
how long you last. The lungs have mechanisms for clearing particulates,
but not oils. And let's not forget that the oil has lots of other
charming things in it (like heavy metals from wear surfaces) by the time
it gets to your lungs.

You are breathing oil-contaminated air all the time, over a cooking
stove or around 2-cycle engines. No one thinks much of it, because it
isn't a hazard.


Well, I'd suggest that most people think more about it than you do. And
in most of those situations, you're getting particulates, not
volatilized oil. You're also breathing through your nose, which is
designed as a filter (i.e. impingement on mucosal linings of the nasal
and sinus passages), which you will not be doing underwater, unless
using a full face mask.

Using an oil sealed compressor to supply breathing air is just stupid,
unless you care nothing for your health.

Keith Hughes