IMI Radalert 100 Series User manual

Operation Manual
Nuclear Radiation Monitor
X
 January 27 2023

 through 2023

 
 
tional Radalert cessories
•Protect® Silicone Boot
•Geigerlink Computer Interface
•IMI Gateway App
r Mission ince 
Please Rememer to e arefl
rond Radioactie Materials
Radalert is a Registered Trademark of International Medcom Inc.

Contents
1 Introduction ..........................................................................1
How the Radalert 100Detects Radiation..............................1
Precautions............................................................................2
2 Features ................................................................................3
The Display............................................................................4
The Switches .........................................................................5
The Detector .........................................................................6
The Input/Output Ports ..........................................................6
3 Operation..............................................................................7
Units of Measurement ...........................................................7
Starting the Radalert 100.....................................................7
Operating in the Dose and Count Rate Modes.......................7
Operating in Timer Mode ......................................................8
Operating Ranges and Response Times................................10
Using the Alert ....................................................................11
The Utility Menu..................................................................12
Interfacing to an External Device..........................................13
4 Common Procedures ...........................................................14
Establishing the Background Count .....................................14
Environmental Area Monitoring ...........................................15
Checking an Object .............................................................15
5 Maintenance .......................................................................16
Calibration ..........................................................................16
Troubleshooting and Service ................................................19
6 Basics of Radiation and Its Measurement .............................21
Ionizing Radiation................................................................21
Measuring Radiation............................................................23
Radiation Measurement Units..............................................24
Higher Than Normal Readings .............................................24
Appendix: Technical Specifications ...........................................26
Limited Warranty .....................................................................28

Radalert 1001
1 Introduction
The Radalert 100is a health and safety instrument that measures
alpha, beta, gamma, and X-ray radiation. Its applications include:
•Monitoring possible radiation exposure while working with
radionuclides
• Ensuring compliance with regulatory standards
• Checking for leakage from X-ray machines and other sources
•Alerting you with an audible alarm if the radiation goes above an alert
level that you set
•Screening for environmental contamination or environmental sources
of radioactivity
• Connecting to a computer or data logger to record and tabulate your
data
How the Radalert 100XDetects Radiation
The Radalert 100uses aGeiger-Mueller tube to detect radiation.
The Geiger tube generates apulse of electrical current each time
radiation passes through the tube and causes ionization. Each pulse
is electron ically detected and registers as acount. ThRadalert
100displays the counts in the mode you choose: microsieverts
per hour (µSv/hr), either counts per minute (CPM) or counts per
second (CPS), or total counts. In conventional units, milliroentgens
per hour (mR/hr) and CPM are used.
The number of counts detected by the Radalert 100varies from
read ing to reading due to the random nature of radioactivity. A
reading is expressed more accurately as an average over time, and
the average is more accurate over alonger time period. For more
information, see “Operating in Total/Timer Mode” in Chapter 3.

2 100
Precautions
To keep the   ingood condition, handle itwith care
and
observe the following precautions:
• Do not contaminate the   by touching it to radioactive
surfaces or materials.
• Do not leave the   in temperatures over 122° F (50° C) or
in direct sunlight for extended periods of time.
• Do not get the   wet. Water can damage the circuitry and
the coating of the mica surface of the Geiger tube.
• Do not put the   in a microwave oven. It cannot measure
microwaves, and you may damage it or the oven.
• If you expect to not use the   for longer than  month,
remove the battery to avoid damage from battery corrosion.
• Change the battery when the battery indicator appears on the display.

 100 3
2 Features
The   measures alpha, beta, gamma, and X-ray radiation.
This chapter briefly describes the  ’s functions. For more
information on how to use the  , see Chapter 3,
“Operation.”
The   counts ionizing events and displays the results on
the
liquid crystal display (LCD) (4). You control which unit of
measurement
is shown by using the mode switch.
Whenever the   is operating, the red count light (1)
flashes each time a count (an ionizing event) is detected.
1Count
Light
2Calibration
Input Port
3Output Port
4LCD
5Mode
Switch
6On/Off/
Audio
Switch
End Panel
7+, –, and
Set Buttons
8Alpha
Window
ETotal Mode
DTimer
CAlert Mode
Indicator
BLow Battery
Indicator
ANumeric
Display
ITimer, Alert,
or Calibration
Set Mode
JUnits of
Measurement
KMenu
LRange Full
FX1000
Mode
HCalibration
Mode
GAverage

4 100
The Display
Several indicators on the LCD show information about the mode setting,
the current function, and the battery condition.
•e numeric display (A) shows the current radiation level in the unit
specied by the mode switch setting.
•A small battery (B) appears to the le of the numeric display to indicate
low battery voltage.
• A radiation symbol (C) appears when the Alert feature is on.
•An hourglass (D) appears during a timed count.
•TOTAL(E) appears when the   is in Total/Timer mode.
•X1000 (F) appears when the radiation level is displayed in X1000
mode.
•AVG (G) appears when the   is showing the average reading
for a timed count.
•CAL (H) appears while you are calibrating the  .
•SET (I) appears when you are setting the Timer, the Alert level, or the
calibration factor, or working in the Utility Menu (the numeric display
shows the setting being adjusted instead of the current radiation level).
•e current unit of measurement (J)—CPM, CPS, mR/hr, or µSv/hr—is
displayed to the right of the numeric display.
•MENU (K) appears when you are in the Utility Menu.
•RANGE:Full (L) appears when the radiation level goes beyond the
range that can be displayed.
1Count
Light
2Calibration
Input Port
3Output Port
4LCD
5Mode
Switch
6On/Off/
Audio
Switch
End Panel
7+, –, and
Set Buttons
8Alpha
Window
ETotal Mode
DTimer
CAlert Mode
Indicator
BLow Battery
Indicator
ANumeric
Display
ITimer, Alert,
or Calibration
Set Mode
JUnits of
Measurement
KMenu
LRange Full
FX1000
Mode
HCalibration
Mode
GAverage

 100 5
The Switches
The   has two switches on the front and three buttons on
the end panel. Each switch has three settings, which are described
below.
Mode Switch (5)
Dose Rate. The numeric display shows the current radiation level
in the selected unit of measurement. In SI units it shows the current
radiation level in microsieverts per hour, from .00to 1100. In con-
ventional units, it shows milliroentgens per hour from .00to 110
.
Count Rate. The display shows the current radiation level in
counts per minute from to 350,000
When X1000 is shown,
multiply the numeric reading by 1,000
to get the complete reading.
Total/Timer. e display shows the accumulated total of counts
starting when the switch is turned to this position, from 0 to
9,999,000. When X1000 is shown, multiply the numeric reading
by 1,000 to get the complete reading.
On/Off/Audio Switch (6)
Audio. The   is on, and it makes a clicking sound
for
each radiation event detected.
On. The   is operating, but audio is off.
Off. The   is not operating.
+, –, and SET Buttons (7)
ese buttons are used for setting the alert level and the timer. ey
are also used for calibration and for using the Utility Menu. For
more information, see “Taking a Timed Count,” “Using the Alert,”
and “e Utility Menu” in Chapter 3 and “Calibration” in Chapter 5.

6 100
The Detector
The   uses a Geiger ube to detect radiation. Alpha
radiation does not penetrate most solid materials, so this Geiger tube has
a thin disk of mica, which alpha radiation can penetrate, on its end.
The screened opening at the top of the   is called the
alpha window (8). It allows alpha and low-energy beta and gamma
radiation to penetrate the mica end of the tube.
CAUTION:The mica end surface of the Geiger tube is fragile. Be
careful not to let anything penetrate the screen.
The Input/Output Ports
There are two ports on the left side of the  .
The calibration inputetera roe port (2) is used for calibrating
electronically using
a pulse generator. For more information, see
“Calibrating Electronically” in Chapter 5.
The output port (3) below the calibration input port allows you to
interface the   to a computer, data logger, earphones,
or other device using a 3.5 mm stereo plug.  
 M ( I   
( I       
  For more information, see “Interfacing to an
External Device” in Chapter 3.