International Medcom Inspector Alert User manual

Operating Manual

Inspector Alert
Nuclear Radiation Monitor
Operating Manual

Copyright 1996, 2005 by International Medcom, Inc. All rights
reserved.

Contents
1 Introduction 1
How the Inspector Alert Detects Radiation 1
Precautions 1
2 Features 3
The Display 4
The Switches 5
The Detector 6
The Input/Output Ports 7
3 Operation 8
Units of Measurement 8
Starting the Inspector Alert 8
Operating in the Dose Rate Modes 8
Operating in Total/Timer Mode 9
Operating Ranges and Response Times 11
Using the Alert 13
The Utility Menu 14
Interfacing to an External Device 15
4 Common Procedures 16
Establishing the Background Count 16
Environmental Area Monitoring 17
Checking for Surface Contamination 17
5 Maintenance 18
Calibration 18
Troubleshooting 20
Service 22
6 Basics of Radiation and Its Measurement 23
Ionizing Radiation 23
Radiation Measurement Units 25
Appendix A Technical Specifications 26
Warranty 28

1
1 Introduction
The Inspector Alert is a health and safety instrument that is
optimized to detect low levels of radiation. It measures alpha,
beta, and gamma radiation. Its applications include:
•Detecting and measuring surface contamination
•Monitoring possible radiation exposure while working with
radionuclides
•Alerting you with an audible alarm if the radiation goes above
the an alert level that you set
•Screening for environmental contamination
•Detecting noble gases and low energy radionuclides
How the Inspector Alert Detects Radiation
The Inspector Alert uses a Geiger-Mueller tube to detect radiation.
The Geiger tube generates a pulse of electrical current each time
radiation passes through the tube and causes ionization. Each
pulse is electronically detected and registers as a count. The
Inspector Alert displays the counts in the mode you choose:
counts per minute (CPM), milliroentgens per hour (mR/hr), or total
counts. In SI units, counts per second (CPS) and microsieverts per
hour (µSv/hr) are used.
The number of counts detected by the Inspector Alert varies from
reading 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 a longer time period. For more
information, see “Operating in Total/Timer Mode” in Chapter 3.
Precautions
To keep the Inspector Alert in good condition, handle it with care,
and observe the following precautions:

2
•Do not contaminate the Inspector Alert by touching it to
radioactive surfaces or materials. If contamination is
suspected, you can replace the rubber strips above and below
the rear label with the extra strips supplied with the Inspector
Alert.
•Do not leave the Inspector Alert in temperatures over 122°F
(50°C) or in direct sunlight for extended periods of time.
•Do not get the Inspector Alert wet. Water can damage the
circuitry and the coating of the mica surface of the Geiger
tube.
•Avoid making measurements with the detector window in
direct sunlight; this could affect the readings if the coating of
the mica surface of the Geiger tube has been damaged by
moisture or abrasion.
•Do not put the Inspector Alert in a microwave oven. It
cannot measure microwaves, and you may damage it or the
oven.
•If you expect to not use the Inspector Alert for longer than
one month, remove the battery to avoid damage from battery
corrosion.
•Change the battery promptly when the battery indicator
appears on the display.

2 Features
The Inspector Alert measures alpha, beta, gamma, and x-ray
radiation. It is optimized to detect small changes in radiation
levels and to have high sensitivity to many common radionuclides.
For more information, see Appendix A, "Technical Specifications."
This chapter briefly describes the Inspector Alert's functions. For
more information on how to use the Inspector Alert, see Chapter 3,
"Operation."
3

The Inspector Alert 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 Inspector Alert is operating, the red count light (1)
flashes each time a count (an ionizing event) is detected.
The Display
Several indicators on the LCD show information about the mode
setting, the current function, and the battery condition.
•The numeric display (A) shows the current radiation level in
the unit specified by the mode switch setting.
•A small battery (B) appears to the left 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 Inspector Alert is in Total/Timer
mode.
•X1000 (F) appears when the radiation level is displayed in
X1000 mode.
•MENU (not shown) appears when you are in the Utility
menu.
4

5
•CAL (G) appears while you are calibrating the Inspector Alert.
•SET (H) appears when you are setting the timer, the Alert
level, and the calibration factor, or working in the Utility
menu (the numeric display shows the setting you are
adjusting instead of the current radiation level).
•The current unit of measurement (I)--CPM, CPS, mR/hr or
µSv/hr--is displayed to the right of the numeric display.
The Switches
The Inspector Alert has two switches on the front, and one switch
and three buttons on the end panel. Each switch has three
settings, which are described below.
On/Off/Audio Switch (7)
Audio. The Inspector Alert is on, and it makes a clicking
sound for each radiation event detected.
On. The Inspector Alert is operating, but audio is off.
Off. The Inspector Alert is not operating.
Mode Switch (6)
mR/hr µSv/hr. The numeric display shows the current
radiation level in milliroentgens per hour from .001 to 100.
When SI units are used, it shows the current radiation level in
microseiverts per hour, from .01 to 1000.
CPM CPS. The display shows the current radiation level in
counts per minute from 0 to 350,000. When X1000 is
shown, multiply the numeric reading by 1000 to get the
complete reading. When SI units are used, the display shows
the current radiation level in counts per second from 0 to
5000.
Total/Timer. The 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 1000 to get the complete reading.

6
Timer Switch (10)
Off. The timer is not operating.
Set. You can now set the length of the timed period using the
+ and - buttons. If the timer is already operating, the display
shows the time remaining in the timed period.
On. The timer is operating, and the display shows the total
counts so far in the timed period.
+, -, and SET Buttons (8)
These buttons are used for setting the alert level and the
timer. They are also used for calibration and for using the
Utility Menu. For more information, see "Taking a Timed
Count," ”Using the Alert,” and “The Utility Menu” in Chapter
3 and "Calibration" in Chapter 5.
The Detector
CAUTION: The mica surface of the Geiger tube is fragile. Be
careful not to let anything penetrate the screen.
Internal—For Inspector Alert Only
The Inspector Alert uses a two-inch round Geiger tube, commonly
called a "pancake tube." The screen on the back of the Inspector
Alert is called the window. It allows alpha and low-energy beta
and gamma radiation, which cannot get through the plastic case
and the stainless steel detector body, to penetrate the mica surface
of the tube. The small radiation symbols on the front label (5) and
the end label (9) indicate the center of the Geiger tube.
External—For Inspector Alert EXP Only
The Inspector Alert EXP has the pancake detector in an external
probe instead of inside the instrument. To connect the probe, plug
one end of the cable into the connector on the end of the Inspector
Alert EXP and the other end to the probe.

CAUTION: The connectors are directional. Be sure to line them
up properly before fitting them together. If the probe is not
connected when you turn the Inspector Alert EXP on, the
instrument will not function properly.
CAUTION: Do not remove the probe while the instrument is on.
The Input/Output Ports
There are two ports on the left side of the Inspector Alert. The
Inspector Alert EXP has a third port on the end panel.
The calibration input 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 Inspector Alert to a computer, data logger, or other
device using a 3.5 mm stereo plug. For more information, see
“Interfacing to an External Device” in Chapter 3.
The probe port on the end panel of the Inspector Alert EXP allows
you to plug the external probe into the instrument.
7

8
3 Operation
The guidelines in this chapter describe how to use the Inspector
Alert.
Units of Measurement
The Inspector Alert is designed both for users of conventional units
(milliroentgens per hour and counts per minute) and for users of
SI units (microsieverts per hour and counts per second). To switch
between conventional and SI units, use the Utility Menu. See
“The Utility Menu” in this chapter.
Starting the Inspector Alert
Be sure that a standard 9-volt alkaline battery is installed in the
battery compartment in the lower rear of the Inspector Alert. Note:
When installing the battery, place the battery wires along the side
of the battery and not under it.
Before you start the Inspector Alert, make sure the timer switch on
the end panel is set to Off.
To start the Inspector Alert, set the top switch to the mode you
want, and set the bottom switch to On or Audio. The Inspector
Alert then does a four-second system check, displaying all the
indicators and numbers.
After the system check, the radiation level is displayed in the
selected mode. Thirty seconds after you start the Inspector Alert, a
short beep indicates that enough information has been collected to
ensure statistical validity.
When using the Inspector Alert, always be sure there is no
obstruction between the detector window and the source you are
surveying or monitoring.

9
Operating in the Dose Rate Modes
When the mode switch is set to mR/hr µSv/hr or CPM CPS, the
numeric display is updated every three seconds. At low count
rates, significant changes in the radiation level displayed can take
up to 30 seconds to stabilize. See “Operating Ranges and
Response Times” in this chapter for more information.
CPM (or CPS) and total counts are the most direct methods of
measurement; mR/hr (or µSv/hr) is calculated using a conversion
factor optimized for Cesium-137, so this mode is less accurate for
other radionuclides, unless you have calibrated the Inspector Alert
for a specific radionuclide using an appropriate source. It is more
appropriate to measure alpha and beta activity using CPM than
using mR/hr. Conversion for alpha and beta emitters is calculated
differently, and the Inspector Alert’s reading in mR/hr may not be
accurate.
The most immediate indicators of the radiation level are the count
light, the audio beep, and the alert. It takes three seconds before
an increase is shown on the numeric display in the dose rate
modes.
Operating in Total/Timer Mode
When the mode switch is set to Total/Timer, the Inspector Alert
starts totaling the counts it registers, and the numeric display is
updated every second.
Taking a Timed Count
When a timed count is taken over a longer period, the average
count per minute is more accurate, and any small increase is more
significant. For example, if one 10-minute average is one count
higher than another 10-minute average, the increase may be due
to normal variation. But over 12 hours, a one-count increase over
the 12-hour background average may be statistically significant.
The Inspector Alert can give you a total count for a timed period of
from one minute to 24 hours. Follow these steps:

10
1. With the Inspector Alert operating, set the Mode switch to
Total/Timer. The display shows TOTAL.
2. Set the Timer switch on the end panel to Set. The display
shows SET, the hourglass, and the most recent timing period
used. The first time you use the timer, the setting is 00:01,
which means one minute.
3. Use the + and – buttons to set the timing period. The timed
period can be for 1 to 10 minutes in one-minute increments,
for 10 to 50 minutes in ten-minute increments, or for 1 to 24
hours in one-hour increments.
4. Set the Timer switch to On. The Inspector Alert beeps three
times and starts counting. The hourglass indicator flashes
during the timed period.
If you want to see how many minutes remain, set the Timer
switch to Set. The display counts down from the time setting
in hours and minutes to zero. For example, if the display says
00:21, 21 minutes remain. Be sure to set the switch back to
On to see the total count when the timed period is finished.
5. At the end of the timed period, the Inspector Alert beeps
three times, and repeats the beeping several times. The
number displayed is the total count.
6. To find the average dose rate for the timed period in counts
per minute, divide the total by the number of minutes.
7. Set the Timer switch to Off to return to normal operation.
As long as the Timer switch is set to On, the timer mode is active
in the background even when the Mode switch is set to one of the
dose rate modes. For example, during and after the timed period,
you can switch back and forth between Total/Timer and mR/hr;
when the timed period is over, the total is displayed whenever you
switch back to Total/Timer. The hourglass indicator is shown on
the display in any mode setting; it is blinking while the timer is
totaling counts.

11
Taking a Total Count
The timer can take timed counts of up to twenty-four hours. In
certain situations, you may want to take a total count without the
timer; for example, taking a count for longer than twenty-four
hours. Follow these steps:
1. Place the Inspector Alert in the location where you plan to
take the count.
2. Note the time.
3. Immediately when you note the time, set the mode switch to
Total/Timer.
4. At the end of the time period, note the time and the total on
the numeric display.
5. Subtract the starting time from the ending time to determine
the exact number of minutes in the timing period.
6. To get the average count, divide the total reading by the
number of minutes in the timing period.
Operating Ranges and Response Times
In some modes, when radiation levels increase over certain preset
levels, the Inspector Alert uses autoranging, automatically
changing to the X1000 scale. Whenever X1000 is shown above
the numeric display, multiply the displayed reading by 1000 to
determine the radiation level. The following table shows the
radiation levels the Inspector Alert measures in each mode and
how they are displayed.

12
Mode Regular Range X1000 Range
mR/hr .001-110 NA
µSv/hr .01-1100 NA
CPM 0-9999 10,000-350,000
(displayed as 10.00-350,
with X1000 indicator)
CPS 0-5000 NA
Total/Timer 0-9999 10,000-9,999,000
(displayed as 10.00-9999,
with X1000 indicator)
Maximum level. When the maximum level for the current mode is
reached, the Inspector Alert beeps for three seconds, pauses for
three seconds, and repeats that pattern. The numeric display
flashes. The beeping pattern and the flashing continue until the
level decreases or the Inspector Alert is turned off.
Display update and response time. In Total/Timer mode, the
numeric display is updated each second. In the dose rate modes,
the numeric display is updated every three seconds. When the
radiation level is less than 6,000 CPM, the reading in any of the
dose rate modes is based on the radiation detected in the
immediately previous 30 seconds. In order to give a quicker
response to changes, when the radiation level exceeds 6,000 CPM
in any 30-second period, the reading is based on the previous 6
seconds, and when it exceeds 12,000 CPM, the reading is based
on the previous 3 seconds, as shown in the following table. This
automatic change in response time is called auto averaging.

13
Radiation level Basis for reading
(after first 30 seconds)
<6000 CPM or <1.75 mR/hr 30 seconds
(<100 CPS)
6000-12000 CPM or 1.75-3.6 mR/hr 6 seconds
(100-200-CPS)
>12000 CPM or >3.6 mR/hr 3 seconds
(>200 CPS)
Note: You can set the response time to 3 seconds at all radiation
levels using the Utility Menu; see “The Utility Menu” in this
chapter.
Using the Alert
The Inspector Alert can sound an audible alert whenever the
radiation reading reaches a certain level. The +, -, and Set buttons
on the end of the Inspector Alert allow you to turn Alert mode on
and off and to set the alert levels.
To use Alert mode, follow these steps:
1. Press the Set button on the end panel. The current alert level
is displayed. It is in CPM, CPS, mR/hr, or µSv/hr, depending
on the Inspector Alert’s current settings. The radiation symbol
and SET icon are displayed.
2. If you want to change the displayed alert level, use the + and
– buttons to adjust the level up or down.
3. When the desired alert level is displayed, press the Set button
again to save the new level and continue in Alert mode.
The radiation symbol is displayed to show that the Inspector
Alert is in Alert mode.
4. If you want to reset the alert level while you are in Alert
mode, press the Set button twice (Off, then Set).

14
5. To turn off Alert mode, press the Set button once.
When you start Alert mode, the Inspector Alert restarts counting,
and beeps after 30 seconds to show that the reading is statistically
valid.
When you first start the Inspector Alert, the alert levels are preset at
.10 mR/hr, and the equivalent in CPM, µSv, and CPS. If you set
the alert level in one mode, the settings for the other modes are
automatically updated to the equivalent values.
The best alert level is one that rarely gives a false alarm, yet warns
you when the radiation is higher than normal.
The Utility Menu
The Utility Menu allows you to change the default settings for
several operating parameters. When you change a setting, it
remains in effect after you turn off the Inspector Alert and until you
change it again.
To activate the Utility Menu, hold down the + button on the end
panel while you turn on the Inspector Alert. The word MENU
appears at the bottom right of the numeric display, and the display
shows 1 for menu option 1. To scroll through the menu, push the
plus (+) and minus (–) buttons. To select an option, push the Set
button. Once an option is selected, use the + and – buttons to
scroll among settings. After you choose the setting you want,
select option 0 to exit the Utility Menu.
The options are:
0 Resume normal operation.
1 Auto Averaging. on (the default) selects Auto averaging; oFF
selects 3-second (fast response) averaging at all radiation
levels.
2 Units of measurement. CPM mR/hr selects counts per
minute and milliroentgens per hour; CPS µSv/hr selects
counts per second and microseiverts per hour.
3 Cal 100 Reset. Selecting this option automatically resets the
calibration factor to 100 and restarts the instrument.

15
4, 5, 6 Reserved for future options.
7 Cal Factor Adjust. Displays the current calibration factor,
which you then adjust to the new factor you want. See
“Calibration” in Chapter 5.
8 Factory Default Reset. Selecting this option automatically
resets the items 1, 2, and 3 to Auto averaging, CPM and
mR/hr, and 100, and restarts the instrument
9 Revision #. Displays the software version number.
Interfacing to an External Device
The lower output jack on the left side of the Inspector Alert is a
dual miniature jack that provides a data output that can be used to
drive a CMOS or TTL device. You can use it to record the counts
on a computer, data logger, or accumulating counter. Use a
3.5 mm stereo plug to access this port. The output at the tip of the
plug provides a positive (3.3 volt) pulse each time the Geiger tube
detects a count. A cable with an RS-232 connector for an IBM PC-
compatible computer serial port and accompanying software are
available from International Medcom.

16
4 Common Procedures
The following sections give instructions for several commonly-
used procedures. With any procedure, the user must determine
the suitability of the instrument or procedure for that application.
Establishing the Background Count
Normal background radiation levels vary at different locations,
even in different areas of the same room. To accurately interpret
the readings you get on the Inspector Alert, it is a good idea to
establish the normal background radiation level for each area you
plan to monitor. You can do this with a timed count. Use the
following steps to get a ten-minute average.
1. With the Inspector Alert operating, set the Mode switch to
Total/Timer.
2. Set the Timer switch on the end panel to Set. Unless you
have previously changed it, the display reads 00:01, which
means one minute.
3. Press the + button nine times. The display should read
00:10, for ten minutes.
4. Set the Timer switch to On. The Inspector Alert beeps three
times and starts counting.
If you want to see how much of the ten minutes remains, set
the Timer switch to Set. The display counts down from ten
minutes to zero. For example, if the display says 00:03,
seven minutes have passed and three minutes remain. Reset
the switch to On to return to the radiation level display.
5. At the end of the ten minutes, the Inspector Alert beeps three
times, and repeats the beeping several times. Note the total
reading.
6. To find the average counts per minute, divide the total by ten
(the number of minutes).
Table of contents
Other International Medcom Measuring Instrument manuals
Popular Measuring Instrument manuals by other brands

Tektronix
Tektronix 7L13 instruction manual

Spirax Sarco
Spirax Sarco Colima Visco Installation and maintenance instructions

elsner elektronik
elsner elektronik KNX SO250 Installation and adjustment

Digga
Digga TORQUE LOGIC Installation, operating and troubleshooting instructions

Midtronics
Midtronics CPX-900 WiFi Quick reference guide

Ankom
Ankom 2000 Operator's manual