RE: Low Background Liquid Scintillation Counter

[Franz Schoenhofer <schoenho@via.at>]

>From: 	Myung Chul Jo[SMTP:mjo@scs.unr.edu]
>Sent: 	Monday, March 16, 1998 11:24 AM
>To: 	Multiple recipients of list
>Subject: 	Low Background Liquid Scintillation Counter
>
>We are investigating a suitable LSC for analysis of low activity samples
>(such as environmental samples). Our normal background counts from our
>current LSC are 50-100 dpm (about 4500 feet above sea level). Only low =
>BG
>LSC I am aware is the TRI-CARB from Packard.=20
>Are there any other similiar systems available?=20
>I would appreciate to know from someone who use low BG LSC. What kind of
>BG levels can I expect from these low BG LSC?  The TRI-CARB is more
>expensive than I can afford at this time. We need a system which can
>discriminate between alpha/beta.
>Thank you in advance. =20
>
>Myung Chul Jo, RSO <mjo@scs.unr.edu>
>EH&S/MS 328
>University of Nevada, Reno
>Reno, NV 89557
>(702) 784-4540(voice)
>(702) 784-4553(fax)


There is an ultra low-level liquid scintillation spectrometer commercially
available. It is the "Quantulus", made by Wallac Oy in Turku, Finland. It
has active shielding and from every side at least 10 cm of lead shielding.
We have been working with low-level LSC since about 15 years. We have four
of these "Quantulus". The background in the tritium window is in the range
of 0.5 cpm, in the window used for radon it is also in the range of 0.5
cpm. It is equipped with alpha-beta separation and the background for alpha
measurements can be reduced to practically zero. We use these instruments
for measurement of tritium, radon in water and air, radium, Sr-90, C-14 in
alcohol, gross alpha+beta etc. Our matrices are drinking water, food, waste
water and all kind of environmental samples. The Quantulus is also the
system of choice in radiocarbon dating. 

In case you need more information, please contact me at my personal e-mail
address. For information from the Wallac company I suggest you contact
Lauri Kaihola at Lauri.Kaihola@wallac.fi. I have another e-mail address
which reads lkai@mail.wallac.fi.

Regards,

Franz




Franz Schoenhofer
Federal Institute for Food Control and Research
Department for Radiochemistry and Radioactivity of Food
Kinderspitalg. 15
A-1095 Vienna
AUSTRIA
tel.: +43-1-40491-520
fax.: +43-1-40491-540