Next message: Richard M. Pisko: "Re: Plexiglass horizon"
A Google search for "mercury vapor pressure" turned up this in
the second site found:
Other materials may emit enough vapor to exceed the permissible
exposure limit (PEL) for inhalation. This vapor pressure does not
need to be large. For example, while the vapor pressure of mercury
is quite low (0.00185 torr), this can easily exceed the PEL for
mercury vapor. Always minimize your exposure to volatile chemicals
and use proper protection such as fume hoods or respirators if their
use can not be avoided or minimized.
Another hit reports
The vapor pressure of mercury is a sensitive function of temperature,
the increase in concentration being in excess of 8% per degree Celsius.
Yet another:
A major advantage to using mercury in a manometer is the low vapor
pressure of mercury, which is 0.0017 torr at 25 oC. This small vapor
pressure can be ignored for all but very low pressure measurements.
-- Bill
