[ RadSafe ] Re:Source in Twin towers

Geo>K0FF GEOelectronics at netscape.com
Mon Oct 5 20:26:34 CDT 2009

Just for the record, a two sided, 20 year self powered exit sign holds right 
at 10 Curies of tritium. In this disaster, there were 100 floors or more in 
each building, 200 floors total. Maybe 10 signs per floor ( probably many 
more as each floor covered one acre) the potential *IF* self luminous signs 
were used would be a minimum of 200 X 10 X 10 = 20, 000 Curies.

I have no standing to recommend what is safe or not, just a tech who 
measures things and reports the findings, leaving the rest to others.

I submit at the time of the disaster, no one knew if the airplanes involved 
contained up to 1000 kg of DU each, or if 10,000 Curies of tritium were 
present, or indeed if there were any calibration sources, nuclear gauges, 
nuclear diagnostic materials, nuclear therapy materials, etc on the site, 
the only sane thing to do is have a team whose *only* concern is radiation 
detection be there and be properly trained and equipped.

Let me recommend a good book to the listmembers "Defusing Armageddon, Inside 
NEST, America's Secret Nuclear Bomb Squad".
The author has no axe to grind in any way but is factually reporting the 
many incidents and "Broken Arrows" that have happened and how each has lead 
to improvements in our readiness factor. Publish 2009 by Norton & Co. Author 
Jeffery T. Richelson.

George Dowell
New London Nucleonics Lab

----- Original Message ----- 
From: "Brennan, Mike (DOH)" <Mike.Brennan at DOH.WA.GOV>
To: <radsafe at radlab.nl>
Sent: Monday, October 05, 2009 4:01 PM
Subject: RE: [ RadSafe ] Re:Source in Twin towers

Hi, George.

I've sampled for tritium on occasion.  Sometimes it has been in
association with a known ongoing source or a spill of tritiated water,
with the goal being to show that there was so little that there was no
need to worry.  I've also sampled landfill leachate and wondered at the
tritium results (I still think there is a confounding factor that gives
false high results, but I don't know what it is).  In all these cases
the risk was vanishingly small and there really wasn't much going on.

In the World Trade Center incident there was a lot going on.  If I had
been involved as a radiation protection specialist I would have told
them that it was not worth the time and risk to sample for tritium.  The
tritium in the signs on the planes and floors that caught fire became
hot water vapor and almost all left with the smoke.  Any signs on other
floors that were crushed released tritium in widely dispersed areas,
most of which escaped as gas or water vapor, most of the rest of it
reacted with material in its immediate vicinity, and only a trivially
small amount would show up in water samples.  Additionally, no one was
drinking the water, let alone was going to be drinking the water
continuously for the next 20 years (or whatever your favorite risk model
uses as an assumption).  I would have stated that, in my professional
opinion, the risks associated with tritium were too small to justify ANY
time or resources being spent on it, so lets get on with the important

I like the rad biz (that's why I work in it).  But I know that just
because I like it doesn't make it the most important thing going on all
the time.  For example, I have tried to keep pointless equipment from
being bought in the name of Homeland Security, because I am firmly and
professionally convinced that the resources could be much better used in
something other than a fixation on RDDs.  I have no problem at all
telling people about radiation issues that I think they should be
concerned about (radon, for example).  But I also believe that part of
my job is to tell them what they should not be worried about, and I
would have said from before the towers fell that tritium was not
something to worry about.

-----Original Message-----
From: Geo>K0FF [mailto:GEOelectronics at netscape.com]
Sent: Monday, October 05, 2009 11:54 AM
To: Brennan, Mike (DOH); radsafe at radlab.nl
Subject: Re: [ RadSafe ] Re:Source in Twin towers

Mike said: "It saddens me that there is anyone who would have felt that
it was worth the time and expense to look for tritium there, or, if
directed to by Upper Management, would not have explained how pointless
it would be."

Mike, as a radiation protection specialiast, does tritium have no
At what level would there be a concern? If the buildings happen to have
used tritium Exit signs, how many thousand Curies of tritium would have
been released?

By measuring, we would know. My lab has 2 portable tritium detectors as
well as the lab based ones.

George Dowell
New London Nucleonics Lab

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