[ RadSafe ] Re: NYC Bans Geiger counters!!!
radproject at sbcglobal.net
Wed Jan 30 12:10:16 CST 2008
This thread made me think of a funny happening. True story.
"Long ago [1975!!] in a land far away" I was doing an informal,
extracurricular radiation survey around Boston with a buddy from Boston
Edison. We were using a high pressure ionization chamber [10" diameter
sphere under high pressure Ar gas fill]. This unit was used routinely in my
work in environmental rad measurements at the time around nuclear plants.
This unit was very sensitive to slight variations in gross gamma at
background rates. Easy to document differences of a few tenths of a microR
per hour between locations.
Unit sort of like the old RSS-111 from Reuter Stokes --drawn aluminum boxes
about 1 foot square, a bit more than a foot high --connected by a cable. My
friend and I had gone to a bunch of spots around Boston one early evening
which we knew would have elevated background due to granite used in their
fabrication or construction: Bunker Hill Monument [it was after normal
visiting hours and closed so we had to climb a short fence to get inside the
stairs leading up it: don't try anything this in NYCity soon], the Christian
Science Church, a granite sarcophagus from an ancient Egyptian princess on
display in front of the Boston Museum of Science, steps of the Mass.
Statehouse, etc. Just a bunch of interesting spots around Boston , measured
for our amusement.
We then decided to make a measurement at ground level near the Prudential
Tower [the central offices for Boston Edison were there at the time] and a
second reading at "The top of the Hub" -- a very neat glass walled bar
looking out over Boston on all four sides [it was dark so the view was quite
nice] 50 or so stories above street level. To get to the top floor we had to
board an elevator in the lobby carrying the two aluminum boxes for the rad
monitoring system connected by the cable from the ionization chamber box box
to the main electronics & stripchart [at the time] recorder box.
As we boarded the elevator --it was evening, and not many people were
around, a security guard rushed over to sternly ask us what we were doing
and what was in the suspicious looking boxes. The two boxes were connected
by a 3/8"or so diameter cable, with metal carrying handles on top that
looked a LOT like the plungers on the devices used on boxes in old movies to
generate a current to blow up dynamite charges.
I told the guard, without hesitating, and quite accurately that the device
we were carrying was "A high-pressure ionization chamber".
He looked at my friend and I with a strangely puzzled look on his face, and
said OK you can go up. He never asked for ID or any explanation of what we
were going to do with this surveydevice. My friend and I had a good laugh on
the elevator about the guard taking it on faith that a "high pressure
ionization chamber" was not something we might blow up or release spreading
"ionization" all over the place like some kind of weapon.
For what it's worth, after making good stable measurements at a dozen
locations all over Boston [all showing doubling, tripling and more of normal
background due to the use of granite in construction], the recorder was
jumping all over the place at the Top of the Hub restaurant and bar. We
could not make a stable reading there.
Later discussions with the maker of the unit [not Reuter Stokes, but a
company I had hired to make several units with special features [including
one with a magnetic tape data recorder in one unit to measure annual turbine
shine dose at the boundary of Vermont Yankee documenting that the plant did
not exceed a VT State limit of 5 mR per year incremental exposure] led to
the realization that these units at the time had magnetic reed switches. The
top of the Prudential building, a few dozen feet above the restaurant, was
covered with microwave relay dishes. The scatter off the microwave dishes
was tripping the magnetic reed switches in our instrument, and making it
impossible to make a reading of background radiation. The most interesting
thing from a radiation protection point of view at the Top of the Hub would
be what kind of microwave exposure workers and the public were receiving
there. Maybe someone has some non-ionizing survey equipment they could take
there if they are visiting Boston. Great place to go for a drink and the
Stewart Farber, MS Public Health
Farber Medical Solutions, LLC
Linac, Medical, & HP Instrument Brokerage
 441-8433 [Office]
 522-2817 [Cell]
 367-0791 [Fax]
email: radproject at sbcglobal.net
----- Original Message -----
From: "Vernig, Peter G." <Peter.Vernig at va.gov>
To: "Mark Sonter" <sontermj at tpg.com.au>; <radsafe at radlab.nl>
Sent: Wednesday, January 30, 2008 9:49 AM
Subject: RE: [ RadSafe ] Re: NYC Bans Geiger counters!!!
Many moons ago, long before 9/11 I had to do an installation and fly
with an ion chamber. I also had a few hand tools, nothing exciting, no
box cutter. Pliers, crescent, wrench, screw drivers, that sort of
thing. I took I it in carry on so I could explain not wanting it to get
stopped and not put on the plane if it worried them. Security guy did
not even bat an eye at the ion chamber but was very concerned about the
Know what made him happy? A business card...........................
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