Re: FW: IH- Propylene

[Gammatron <gammat@swbell.net>]

Eric Cowdrey wrote:
> 
> This looks like a job for RADSAFE.
> 
> -----Original Message-----
> From: owner-ih-list@intr.net [mailto:owner-ih-list@intr.net] On Behalf
> Of mjame@ag.cyanamid.com
> Sent: Monday, March 15, 1999 11:34 AM
> To: ih-list@lists.aiha.org
> Subject: IH- Propylene
> 
> We have received an MSDS from a supplier of propylene, which states
> "Industry
> experience has shown that propylene may contain small amounts of radon..."
> The
> MSDS also cautions about gamma radiation emanating from equipment containing
> propylene, as well as the potential to inhale alpha particles if entering or
> working on opened equipment.  Unfortunately, the MSDS supplier cannot
> provide
> any insight regarding these statements.  Can the list enlighten me regarding
> the
> presence of radon in propylene?
> 
> Thanks in advance.
> 
> Mike James
> American Cyanamid Company
> Box 817
> Hannibal, Missouri 63401
> 573-769-2011
> 
> Statements and opinions are my own and do not reflect those of American
> Cyanamid
> or American Home Products.
> 
> **************************************************************
> 
> Eric Cowdrey
> Radiation Protection Officer
> Department of Medical Physics
> Manitoba Cancer Treatment and Research Foundation
> 100 Olivia Street
> Winnipeg, Manitoba    R3E 0V9
> CANADA
> 
> Tel (204) 787-2166
> Fax (204) 775-1684
> e-mail ericc@mctrf.mb.ca
> 
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As I understand the process; depending on the geologic zone from where
they produce natural gas, radon is present at varying concentrations.
If the natural gas is held prior to processing for a significant lenght
of time, most of the radon present will decay into it's particulate
daughters. If the natural gas is not stored prior to processing and has
been produced from a gas field with a high radon concentration, then as
they process the gas the radon "cooks off" at about the same temperature
as propane.
It is from the propane that I believe they produce the propylene.
This is how the radon daughters can find their way into propylene
products.
You can also find similar radon daughter contaminations in propane
tanks. Again, the level of radon daughters plated out to the inside of
propane tanks depends on the time the natuaral gas and propane was
allowed to be stored. 
At least that is how I understand it. I am not a chemist.

C. Gallagher
Gammat@swbell.net
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