Hi,
Dosimeters are devices used to measure your exposure to hazardous
environments, particularly when the hazard is cumulative over time,
meaning that you are exposed on a daily basis to the hazard in small
amounts. There are dosimeters available with rate meters. This
adaption is generally inexpensive and measures the rate of change for
a time exposure. This could give you the information you are looking
for in deciding whether or not to leave the area, or stick it out.
Normally you measures heavy fallout in thirty-second periods, and
light fallout over a ten-minute period. The rate meter has two
internal scales that read the radiation flux directly in rems for each
period.
The normal ranges of mrems for the US in yearly dosages is 360 mrems
(3.6. mSv), and a war time during fallout you would need one that
measures up to 500 rems (5 Sv) which is basically a lethal dose.
Medium ranges, such as "occupational exposures" could be in the 500
mrem (5 mSv) range.
The dosimeter is based on a device called an electrometer, but is far
more rugged in design and form. The device works by using two
electrodes which are charged through an external connection .Since
they both have the same charge, they repel each other (just like two
positive magnets repel each other). As radiation ionizes the
electrodes, the charge of the electrodes begins to fade, and they
begin to move away from the zero calibration and this is displayed
against a scale.
Chargers for dosimeter devices are powered normally by a battery. The
charger contains an electronic circuit that steps the battery voltage
up quite a bit. You press the end of your dosimeter into the charging
electrodes and it resets the device.
abstract " A dosimeter or rate meter is the simplest and most portable
means of determining whether you need to seek protection. These tools
can also help you manage your risk by showing you your level of
exposure, and can help you decide how much longer you want to keep
working in a warm or hot zone.
The RAD60, Personal Alarming Dosimeter can be extremely useful to
personal, medical, scholastic, airport x-ray, industry, and military
applications. These dosimeters are rugged precision instruments about
the size of a small pager, and are used to measure accumulative doses
or current dose rates of gamma (X-ray) radiation. A belt clip comes
standard with the RAD60, and can also be used to attach the dosimeter
to an individual's pocket or to any available object in an area to be
monitored for total radiation exposure. A reading may be made at any
time by merely glancing at the easy-to-read digital display."
...
"People can normally handle 10 R per day for a few days with no
long-term side effects. For a small percentage of people, exposures of
200 R to the whole body in a day may prove lethal if no medical help
is available, though the person would not normally die for several
weeks. At 350 R, perhaps 5% of the exposed group would die within a
month. At 450 R, half of the exposed group would probably die without
medical attention, and at 650 R, most would die without intense
medical care. "
RADOS-60 - Electronic Personal Alarming Dosimeter / Rate Meter
http://www.tacda.org/products/product.php?product_id=RAD60
price is listed at 349.95
Radiation Detection and Measurement
http://216.239.63.104/search?q=cache:C_72OpZ7sXcJ:www2.fpm.wisc.edu/safety/Radiation/2004%2520Manual/chapter%25207.pdf+personal+dosimeter+%2B%22rate+meter%22&hl=en
A Generic Standard Operating Procedure
http://216.239.63.104/search?q=cache:d10nCKdQsPMJ:hps.org/hsc/documents/Radiation_detection.pdf+personal+dosimeter+%2B%22rate+meter%22&hl=en
Local Rules for Work with Ionizing Radiation
http://www.st-andrews.ac.uk/services/safety/webpages/radiation/11.html
links of interest
Dosimeter Radiation Detecting Equipment
http://www.dosimeter.com/
Electronic Personal Dosimeters
http://www.perspective.co.uk/d-commerce/page14.html
Personal Dosimeter Management System
http://www.saic.com/products/security/pdms/
(That is software to allow you to manage your personal Dosimeter in
your home using your own computer)
Google Directory Monitors and Dosimeters
http://directory.google.com/Top/Science/Instruments_and_Supplies/Laboratory_Equipment/Radiation_Measurement/Monitors_and_Dosimeters/
(a list of prominent Dosimeter suppliers)
Dosicard - Dosiman Electronic Personal Dosimeters in Credit Card Size
http://www.canberra.com/products/579.asp
Radiation Control Devices and Personal Dosimeters online store
http://www.sensorsportal.com/HTML/E-SHOP/e-shop_7.htm
If you have any questions regarding, please feel free to use the
Clarification function and I'll get back to you as soon as possible.
thanks,
webadept-ga |
