Re: Request for INFO on AWARE Electronics

[Karin Gordon <kgordon@cc.UManitoba.CA>]

About seven years ago, we purchased the AWARE monitor (with a simple GM
probe). The AWARE monitor consists of a radiation detector (usually a GM
probe) attached to a computer - with ordinary telephone cable - carrying
the high voltage to the detector and the signal back tot he computer.
Nifty device, and cheap - only about $150.00 for the detector and
software. These GM probes are usually calibrated using the 660  KeV
gamma rays from Cs-137, and are not energy compensated.   The
radioisotopes most commonly used in nuclear medicine emit gamma rays in
the range of 80 - 360 KeV.  At these gamma ray energies  the ratio of
observed  to real dose is highly variable, depending on the energy of
the incident gamma ray and the photon energy response curve of the
detector.  So the dose we saw was certainly NOT the dose we got.  To
accomplish a WYSIWYG  dose response for this instrument in  the nuclear
medicine environment this we should have purchased the energy
compensated GM probe. So the system was interesting, but not of much use
for our need to accurately measure dose rate and integrated dose - it
sat in a drawer. We could have purchased an energy compensated  GM probe
from AWARE, but had in the meantime had purchased some other survey
meters which satisfied our requirements.

However, several years later, we found an excellent use for this
technology.  At the time we were doing gynecological (uterine)
brachytherapy using Cs-137 and a manual afterloading technique.  For
those of you who aren't familiar with this therapy, in the operating
room a  hollow applicator apparatus is  installed in the patient's
vagina and uterus and secured in place with packing and sutures to the
vaginal introitus.  After radiological verification of the applicator
position,  the patient is returned to the ward and a bit later the
Cs-137 source rods are manually installed into the patient's applicator
apparatus.  The patient is required to stay in bed, lying flat, for
several days until sufficient radiation dose has been delivered to the
target tumour tissue, at which point, the Cs-137 source rods are
manually removed before the applicator is removed.  Many patients
required analgesia because of uterine cramping and the muscular
discomfort caused by lying flat in bed, almost motionless  for up to 72
hours.  Some of our elderly or confused patients would occasionally get
out of bed and might wander down the corridor. This is bad for the
patient because the source applicator might shift internally vis-a-vis
her anatomy, and bad for radiation safety on the ward because there was
about 50 mCi of mobile Cs-137. We needed a radiation detector system
that would sense an increase in ambient radiation dose rate and
immediately trigger an audible alarm at the nursing station, some 20
metres down the corridor from the brachytherapy patient bedroom.  The
system was set up on the ward, with a radiation detector mounted on the
wall outside each brachytherapy bedroom  linked to a single computer by
the nursing station.  The system worked very well as an alarm for
wandering patients, and we were able to computer anlayze the radiation
dose data from each detector.  Our radiation therapy radiation safety
staff were quite satisfied with this system and the nurses were relieved
to have an effective alarm.

I am considering using the system (with energy -compensated probes) to
measure integrated radiation doses in patient bedrooms adjacent to I-131
radionuclide therapy patients, and for other area monitoring projects in
certain radioisotope work and storage areas. 

I found the people from AWARE to be very helpful, and would happily
recommend their product, with the caveat that you purchase the
appropriate AWARE detector to obtain accurate measurements.

Karin Gordon
Radiation Safety office		kgordon@cc.UManitoba.ca
Health Sciences Centre		phone:	(204) 787-2903
Winnipeg, Manitoba		fax:	(204) 787-1313





The patients The occasional  patient was elderly and a bit confused,
and

presley.j@atomcon.gc.ca wrote:

>      Fellow Radsafers,
>
>      A colleague has come across a company
>      on the Web called AWARE Electronics.
>
>      They seem to be selling radiation monitors (geigers)
>      for use by the general public. They are located
>      in Wilmington DE, USA.
>
>      Their site is :
>      www.aw-el.com/index.htm
>
>
>      I would like to know if anyone has any
>      experience in dealing with this company
>      or any other relevant info.
>
>      Please respond to me directly.
>
>      Jim Presley
>      Health Physicist
>      Atomic Energy Control Board
>      presley.j@atomcon.gc.ca