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Previous by Date: Subject: Re: Mercaptan in Gas Suppy Date: Wed, 8 Apr 2009 14:40:38 -0600 Author: fwblack

Next by Date: Subject: Thank You Date: Wed, 8 Apr 2009 20:17:09 EDT Author: Jim Kaufman

Jim,

Here is a link to a report for a study conducted for the Consumer Product 
Safety Commission in 1987 which discusses the loss of odorant due to 
oxidation (primarily ethyl mercaptan to diethyl disulfide) by rust in 
propane cylinders. The same would likely be true for gas sitting in 
pipelines, unused for extended periods. The study led to a change in 
propane filling procedures, whereby the cylinders are now double flushed 
when filling to help ensure the odorant is not oxidized fully on first 
introduction. 

http://www.cpsc.gov/LIBRARY/FOIA/foia02/os/propanept1.PDF

The loss of odorant is also shown to occur upon exposure to untreated 
concrete. The issue there is that an occupant may enter a closed space, 
smelling "gas," closes the offending valve, leaves, sealing the space 
behind them. Upon returning, the "gas" odor is gone (in reality only the 
odorant has been oxidized by the lime in the concrete, the flammable gas 
remains), the occupant tries to reignite the fuel source and is caught in 
the conflagration of the residual gas.

Hope this offers some further explanation.

Best Regards,
-Kevin

*********************************************************
Kevin J. Beltis
Director of Health, Safety and Environment
 TIAX LLC
15-307 Acorn Park
Cambridge, MA 02140-2130

TIAX, "Powered by Innovation"

*******************************************************

TIAX, LLC is a privately held company at the intersection of business and 
technology. TIAX builds on a rich heritage based on creating business 
opportunities and growth through the power of science, technology, and 
innovation.



From:
Jim Kaufman 
To:
DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Date:
04/08/2009 02:53 PM
Subject:
[DCHAS-L] Mercaptan in Gas Suppy
Sent by:
DCHAS-L Discussion List 


Has anyone encountered the situation where the odorant smell from the 
burner gas supply changed when the gas was not used for several months? If 
so, any explanation why?
 
The individual who posed this question to me said that his "lost its 
rotten smell and now smells slightly musty and is much less noticeable".
 
Thanks ... Jim
 
James A. Kaufman, Ph.D.
President/CEO

The Laboratory Safety Institute (LSI)
A Nonprofit International Organization for
Safety in Science and Science Education
www.LabSafetyInstitute.org

192 Worcester Road, Natick, MA 01760-2252
508-647-1900 Fax: 508-647-0062
Cell: 508-574-6264 Res: 781-237-1335
jim**At_Symbol_Here**LabSafetyInstitute.org 
P We thank you for printing this e-mail only if it is necessary
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Jim,

Here is a link to a report for a study
conducted for the Consumer Product Safety Commission in 1987 which discusses
the loss of odorant due to oxidation (primarily ethyl mercaptan to diethyl
disulfide) by rust in propane cylinders. The same would likely be true
for gas sitting in pipelines, unused for extended periods. The study led
to a change in propane filling procedures, whereby the cylinders are now
double flushed when filling to help ensure the odorant is not oxidized
fully on first introduction. 

http://www.cpsc.gov/LIBRARY/FOIA/foia02/os/propanept1.PDF

The loss of odorant is also shown to
occur upon exposure to untreated concrete. The issue there is that an occupant
may enter a closed space, smelling "gas," closes the offending
valve, leaves, sealing the space behind them. Upon returning, the "gas"
odor is gone (in reality only the odorant has been oxidized by the lime
in the concrete, the flammable gas remains), the occupant tries to reignite
the fuel source and is caught in the conflagration of the residual gas.

Hope this offers some further explanation.

Best Regards,

-Kevin


*********************************************************

Kevin J. Beltis

Director of Health, Safety and Environment

 TIAX LLC

15-307 Acorn Park

Cambridge, MA 02140-2130


TIAX, "Powered by Innovation"


*******************************************************


TIAX, LLC is a privately held company at the intersection of business and
technology. TIAX builds on a rich heritage based on creating business opportunities
and growth through the power of science, technology, and innovation.








From:
Jim Kaufman <Labsafe**At_Symbol_Here**AOL.COM>

To:
DCHAS-L**At_Symbol_Here**LIST.UVM.EDU

Date:
04/08/2009 02:53 PM

Subject:
[DCHAS-L] Mercaptan in Gas Suppy

Sent by:
DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**list.uvm.edu>






Has anyone encountered the situation where
the odorant smell from the burner gas supply changed when the gas was not
used for several months?  If so, any explanation why?

 

The individual who posed this question to
me said that his "lost its rotten smell and now smells slightly musty
and is much less noticeable".

 

Thanks ... Jim

 

James A. Kaufman, Ph.D.

President/CEO


The Laboratory Safety Institute (LSI)

A Nonprofit International Organization for

Safety in Science and Science Education

www.LabSafetyInstitute.org


192 Worcester Road, Natick, MA 01760-2252

508-647-1900 Fax: 508-647-0062

Cell: 508-574-6264 Res: 781-237-1335

jim**At_Symbol_Here**LabSafetyInstitute.org 

P We thank you for
printing this e-mail only if it is necessary


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Deals on Dell Netbooks - Now starting at $299

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