User manual

RADIOACTIVITY IN FOODS, BEVERAGES AND OTHER
ITEMS:
Levels of contamination generating an increase of perhaps 20
or so µR per hour will be immediately evident by way of
higher readings next to food.
To check food or other items for lower levels of contami-
nation, simply compare background reading to reading with
item next to RM-60. For example, start PC collecting radia-
tion data (Menu: "Capture" sub-menu "Display Current In-
put"). After several minutes, note average background read-
ing at bottom right of screen. Next place RM-60 on-in box
of fish, etc. and zero out (reset) average at bottom right of
screen (Press F1 then Z). Wait a few minutes then note any
increase in average as compared to background average.
(Make sure when moving RM-60 to food, you are not also
moving it closer to a radioactive item like a brick floor or
wall).
There are many ways you could use the programs to detect
very tiny levels of contamination (2 or so µR/hr.). One meth-
od is as follows. Place RM-60 on table. Start radiation file
with added message "BACKGROUND". Run for 20 minutes
or so then close file. Don’t move RM-60. Place item to
check on-around RM-60. Start new radiation file with mes-
sage "WITH ITEM". Close this file after approx. 20 minutes.
Repeat "BACKGROUND" and then "WITH ITEM" process
several times, each time with a new unique file name. Now
look at a summary of each file (Menu: Display/Edit/Clear
Summary) and compare average radiation level of the BACK-
GROUND files to the WITH ITEM files.
To thoroughly analyze food or beverages for extremely low
levels of contamination would take a lab full of very complex
equipment. Nevertheless, your RM-60 can warn you of very
low levels of radiation.
If you desire to measure even lower levels of radiation from
substances such as edible items, you can increase your ability
to distinguish a very small increase in reading from your RM-
60, over and above fluctuating background radiation, by
placing your RM-60 in a lead brick enclosure. The lead will
block out all but the more energetic cosmic rays, cutting your
background reading by about 50%. By placing the sample
next to the back of the RM-60, within the lead shield, you
will be able to distinguish very low levels of radiation. 4" x
8" lead bricks cost about $30 each. If you desire some lead
bricks, contact Aware Electronics for current prices.
EFFECTS OF IONIZING RADIATION
Unlike radio waves, microwaves, infrared rays, and visible
light, radiation from radioactive substances ionize materials
they pass through, that is, radiation from radioactive sub-
stances split the molecules of materials they pass through, into
charged particles. Ionizing radiation can cause the formation
of free radicals. In addition, disruption of molecules by
recoiling atoms, as happens with alpha bombardment, is also
a factor.
Radiation sickness results from extremely high doses of ioniz-
ing radiation, and is usually characterized by internal bleeding
and various changes in tissue structure.
NOTE: Additional information is contained in the "readme"
file. Read it with your text editor or with DOS by typing
"TYPE README.TXT | MORE" or by typing it on your
printer ("COPY README.TXT PRN"). Be sure to read it.
TEST OF RM-60 RAD. MONITOR TUBE
Tube Data: Type LND 712
Window: Areal Density: 1.5 to 2.0 mg/cm
2
, Eff. Diameter:
0.360", Area: 0.102 Sq. In., Material: Mica
Wall: Thickness: 0.012", Eff. Length: 1.5", Eff. Diameter:
0.566", Material: 446 SS
Neutron Sensitivity With Pu-Be inclusive of Gamma Emission
@ the given neutron flux:
Tube type 712:
0.7 CPS/Neutron/CM
2
/SEC (Window)
1.0 CPS/Neutron/CM
2
/SEC (Side)
The RM-60 and software are digitally locked to the tube. No analog adjust-
ments are necessary. Each tube has passed all examinations, inspections,
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