KWJ Pocket CO 300 User manual

Rev. 2.0
Read all of the information in this booklet before using
Pocket CO.
Many factors can affect air quality. This instrument will give a
dependable indication of CO levels but should not be considered
an all-inclusive monitor for overall air quality. Pocket CO is only
one tool for CO measurement or CO dosimetry for personal use.
Pocket CO’s Self-Test checks most of its functionality but does
not test the CO sensor which can only be tested with actual
exposure to carbon monoxide. Monthly "bump" testing of the
Pocket CO with a source of carbon monoxide is recommended.
KWJ sells a CO bump test kit for this purpose.
Pocket CO is small and light enough to be transported in your
pocket. However Pocket CO should not be operated while in your
pocket. To detect CO Pocket CO must be well exposed to your
surrounding environment (e.g. on your key chain attached to
your dashboard or uniform or worn around your neck).
In the beginning of 2007, the manufacturer of Pocket CO, Transducer
Technology, Inc., was merged into WJ Engineering Inc. The two
companies had been cooperating for two years, and now are combined as
one corporate entity, under the name of WJ Engineering Inc., a company
that has been engaged in the manufacture of gas detection instruments
since 1993. Production, sales and financial matters are handled primarily
by the parent company, while research and new product development are
the focus of the former Transducer Technology, Inc., now known as
Transducer Technology Division.
WARNING
!
NOTIC

Rev. 2.0
1
IND X
1. Introduction 2
2. Specifications 3
3. Using Your Pocket CO 5
3.1 Normal Operation 5
3.2 Turning Pocket CO Off 5
3.3 Using the Backlight 6
3.4 Viewing Dosimetry Information 6
3.5 Understanding Alarms 6
3.6 Understanding Dosimetry/TWA Warnings 9
3.7 Replacing the Battery 11
3.8 Using the Menu 13
3.9 Calibration
14
3.10 Additional Usage Information 15
4. Glossary of Terms 16
5. Care and Maintenance 17
6. Contact Us 18
7. Warranty 19
8. CO Health ffects Inside back cover

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1. Introduction
Pocket CO Model 300 has been designed as a simple and
effective tool to determine, measure, or record Carbon Monoxide
(CO) levels in any environment. The instrument has been
programmed based on guidelines for indoor and outdoor CO
exposure from several organizations, including OSHA and
ACGIH. Alarms are factory set at 50PPM, the ACGIH maximum
recommended short-term exposure of 125PPM, and a death
hazard of 400 PPM CO.
Low levels of CO, typically less than 10 PPM, are not considered
especially hazardous, but they do indicate a source of CO.
Sustained levels above 25 PPM for 8 hours, and short-term
exposure to more than 125 PPM CO, should be avoided. Seek
clean air, ventilation, or any other means to eliminate exposure.
Get more information online at http://www.kwjengineering.com
and at http://www.detectcarbonmonoxide.com.
Pocket CO Model 300 is a stand-alone unit, and because of its
small size can be carried on a key ring, clipped to a worker’s shirt
pocket, or attached to the dashboard of a vehicle or piece of
equipment. Pocket CO is designed specifically to be affordable
and easy to use by health professionals and concerned
homeowners. The device can be used in CO detection
applications such as OSHA enforcement, fire service exposure,
parking garages, warehouses, municipal buildings, hotel rooms,
home furnace inspection and barbecue areas; and for mobile
measurements on boats, cars, trucks, trains, airplanes, and
anywhere else Carbon Monoxide exposure is possible.

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2. Specifications
Size: 2.66 x.1.40 x 0.61 inches (67.6 x 35.6mm x15.5 mm)
Weight: < 1 ounce (28 grams)
Range: 5-500 PPM CO
Response time: < 90 seconds to 90%
Operating
temperature:
32-105 F 0-40 C displayed; readings automatically
compensated.
Pressure effects: Reading decreases with decreasing pressure down to 70%
at 10 000 ft
Humidity limits: 15-85% RH non-condensing
Alarms:
(82 dB buzzer @ 24
in LED Backlight
Vibrator)
Optional first alarm at or above 50 PPM.
Second alarm at or above 125 PPM.
Third alarm at or above 400 PPM.
Hourly warning when CO above the 8-Hour 25 PPM ACGIH
TWA.
Temperature above 50
o
C / 122
o
F: “HOT” displayed
Temperature below 0
o
C / 32
o
F: “COLD” displayed
Low battery warning: “BATT” displayed
Sampling method: Gaseous diffusion.
Interferences: None significant except hydrogen.
Periods of Operation: “12-Hour” and “Always On”
Display: Digital LCD with backlight in increments of 1 ppm.
User interface: Single button operation.
Dosimetry
(12-Hour Detection
period only):
Calculates and records: “MAX” maximum exposure (ppm)
“TIME” time of max. exposure (minutes since turned on)
“TE” total exposure in ppm-hours
8-hour “TWA” time weighted average.
Tests: Self-Test on startup checks circuitry alarms battery and
operating temperature. Does not check sensor.
Calibration: Recommended at least 1x per year or whenever accuracy
of reading is critical.
Sensor: Transducer Technology T-Series electrochemical.
Battery information: Battery check on startup and during operation. User
replaceable CR2450 coin battery.
Warranty: Instrument including sensor: Two years.

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Display with backlight
Buzzer
Button
Red LED Alarm
Rear entry holes for gas
(Do not block)
Screw for battery
compartment cover
Side entry
holes for gas
(Do not
block)

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3. Using Your Pocket CO
3.1 Normal Operation:
The information below describes how to turn Pocket CO on for
normal operation with one of two possible detection periods:
12-Hour Detection: With Pocket CO off quickly push and release
the button. The display will show “12HR”. The instrument will
perform a brief self-test and then show the current CO reading
(PPM). The display will update with a new reading of CO every 5
seconds for a 12-Hour period before turning off automatically.
Using this detection period will help to prolong battery life.
Continuous Detection: With Pocket CO off quickly push and
release the button twice . The display will show “ON”. The
instrument will perform a brief self-test and then show the
current CO reading (PPM). The display will update with a new
reading of CO every 5 seconds and will continue to do so until
turned off by the user. This mode is useful if protection from CO
is required over a prolonged period of time such as on a trip or
long drive. Note that dosimetry information is not recorded or
reported when running in Continuous Detection.
3.2 Turning Pocket CO Off:
To turn Pocket CO off during normal operation quickly push and
release the button once (the backlight will turn on) followed by
pushing and holding the button down. After 2 seconds the red
light will flash and Pocket CO will turn off. Note that this
procedure should be followed even if the backlight is already on
because Pocket CO is alarming.

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3.3 Using the Backlight:
During normal operation, quickly push and release the button
once. The backlight will turn on for a short period of time. Please
note that excessive use of the backlight will reduce Pocket CO’s
battery life.
3.4 Viewing Dosimetry Information:
When running in the 12-Hour Detection period Pocket CO
maintains CO dosimetry information. Dosimetry information
allows you to track your total-exposure to carbon monoxide (TE)
and your 8-hour time-averaged exposure (TWA). It also keeps
track of the maximum concentration of CO measured (MAX) and
when this maximum occurred (TIME) in minutes since being
turned on. Also reported is the total running time (RUN) in
minutes. Pocket CO will save this information until Detection
Mode is entered again. For a more detailed discussion of TE and
TWA see Section 3.6.
To view the dosimetry information during normal operation
quickly push and release the button two times (the backlight will
turn on after the first push). The dosimetry information will be
displayed after a moment starting with the word “DOSM”. After
all of the dosimetry information has been displayed Pocket CO
will resume normal operation.
The dosimetry information from the last use of the 12-Hour
Detection period may also be recalled after Pocket CO has turned
off. With Pocket CO off, quick-push the button three times. The
display will show “DOSM”, and then display the dosimetry
information from the last use of the 12-Hour Detection period.
After displaying this information, Pocket CO will turn back off.

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3.5 Understanding Alarms:
Pocket CO is equipped with the following alarm mechanisms:
• A loud 82 dB beeper (at 24 inches).
• A display backlight.
• A bright red LED on the top of the instrument.
• A vibrator.
Pocket CO is programmed to repeatedly pulse all of these alarms
when the CO exposure reaches or exceeds certain limits. These
limits are pre-programmed at the following levels:
• CO level between 50 PPM and 124 PPM:
Alarm beeper/LED/Vibrator pulse once every 20 seconds.
• CO level between 125 PPM and 399 PPM:
Alarm beeper/LED/Vibrator pulse once every 10 seconds.
• CO level exposure at or above 400 PPM:
Alarm beeper/LED/Vibrator pulse once every 5 seconds.

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These are known as “instantaneous” alarms, since Pocket CO will
alarm as soon as the level of CO reaches or exceeds these
levels. The alarms at these levels are designed to protect you
from the immediate health effects of carbon monoxide. Pay
attention to your Pocket CO when it alarms and vacate the area
until the source of the CO can be found and addressed.
The 50ppm is an optional, low-concentration alarm, which can be
disabled using the Menu (see Section 3.8).
The Pocket CO will also pulse its alarms during the following non-
CO related situations:
• Self Test: One alarm pulse is normal and expected during
the Self Test.
• Temperature above 50oC (122oF) or below 0oC (32oF):
Alarm pulses, plus “HOT” or “COLD” on the display.
• Sensor Malfunction: One alarm pulse, plus “SNSR” on the
display. Note that absence of this alarm does not necessarily
guarantee that the sensor is working normally.

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3.6 Understanding Dosimetry and TWA Warnings:
When run in the 12-Hour Detection period, Pocket CO keeps
track of dosimetry information, which includes your total-exposure
and time-weighted average exposure.
Total-Exposure (TE) is a measure of the amount of CO you’ve
been exposed to over a length of time, and is measured in ppm-
hours.
Example: If from the time you turned on Pocket CO, you were
exposed to 25ppm for 5 hours, and then 10 ppm for 1 hour, your
Total Exposure would be:
Total Exposure = [ (25ppm x 5 hours) + (10ppm x 1 hour) ]
= 135 ppm-hours
Time-Weighted Average exposure (TWA) gives you an idea of
how much CO, on average, you’ve been exposed to, and is
calculated as follows:
TWA = Total Exposure to CO (in ppm-hrs) / 8 hours
Example: If your total exposure was 135 ppm-hours (as in the first
example), your 8-Hour TWA at that point would be:
TWA = 135ppm-hours / 8 hours
= 16.9 ppm
The TWA is called “time-weighted” because its calculation weighs
more heavily exposure that took place over a longer period of

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time. Hence, an additional exposure to a large amount of CO, but
over a very short period of time (e.g. 1-2 minutes), would not
largely affect the TWA calculated in the second example.
The American Conference of Governmental Industrial Hygienists
(ACGIH) has published a recommended limit of 25ppm for an 8-
Hour TWA. Based on this limit Pocket CO will issue a warning if
you have exceeded this average over 8 hours. If Pocket CO has
been on less than 8 hours it will also issue an hourly warning if
your current TWA puts you on track for exceeding this limit in 8
hours. This warning consists of 2 pulses of the alarm along with
the messages “WARN” “TWA” shown on the display. Table 1
summarizes these warnings:
Hours Since
Turned On
Warning if TWA
Exceeds This Value
1 3.1 ppm
2 6.2 ppm
3 9.3 ppm
4 12.5 ppm
5 15.6 ppm
6 18.7 ppm
7 21.8 ppm
8 or more 25 ppm
Table 1: Hourly TWA Warnings
Note that when Pocket CO is left on for more than 8 hours the
Total Exposure and TWA are calculated based on the most recent
8 hours of measurements.
Note that dosimetry information is not recorded or reported
when running in Continuous Detection (see Section 3.1). This also
means that no TWA warning will sound.

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3.7 Replacing the Battery:
The lifetime of the battery in Pocket CO will vary depending on
usage. With typical usage of 5 days per week and minimal
alarming the battery should last up to 1 year. But if Pocket CO
alarms often or the backlight is used excessively battery life will
be reduced. Battery life may also be reduced if Pocket CO is used
or stored in a cold environment.
Pocket CO will let you know that the battery is weak by either:
 Displaying “BATT” during the Self Test.
 Sounding the alarm and displaying “BATT” for several
seconds during normal operation.
When you see the “BATT” warning you have some time left
before the battery dies but you should take action soon to
replace the battery. When the battery becomes too low for Pocket
CO to operate Pocket CO will display “----“.
The battery in Pocket CO is easily replaceable and available at
many stores. Be sure to purchase a new CR2450 coin battery for
replacement (any brand) and insert it according to the steps
shown in Figure 1.

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1. Turn Pocket CO off.
Remove screw, and
put aside (don’t lose
it!).
2. Use coin to
remove battery
cover. Turn coin
clockwise . Battery
cover will pop off.
3. Remove old
battery. Wait 10
seconds before
inserting new one.
Check inside of
battery cover for
calibration due date.
4. Insert new battery,
positive (+) side
facing up.
5. Push battery
forward as far as it
will go.
6. Replace cover, as
shown. Cover will
snap into place.
Replace screw.
Figure 1: Replacing the Battery
Note that immediately after replacing the battery the display may
show “SNSR” or high-levels of CO. This is a normal effect and
the instrument will again function normally after several minutes.
When changing the battery always check the inside of the
battery cover to see when the next calibration due date is. See
Section 3.9 for important information about calibration.
Always wait at least 24 hours after changing the battery before
attempting to calibrate Pocket CO.

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3.8 Using the Menu:
Pocket CO has a menu that allows you to:
1. Enable / disable the vibrator.
2. Choose from 3 different buzzer sounds.
3. Enable / disable the low-concentration alarm (50 PPM).
To access the menu with Pocket CO off quickly push and release
the button four times. The display will show “MENU” and if the
button is not pushed again Pocket CO will give access to the
menu.
To step through the menu items listed above quickly push and
release the button. For each menu item the display will alternate
between the name of the item and the current setting as
summarized in Table 2:
Menu Item Display
Shows Value 1 Value 2 Value 3
1) Vibrator “VIBR” “ON” = Vibrator On “OFF” = Vibrator Off N/A
2) Buzzer Sound “BUZZ” “BZ 1” =
3 loud beeps
“BZ 2” =
Combination low/high
pitch
“BZ 3” =
3 soft
beeps
3) 50 PPM Alarm “A 50” “ON” =
50 PPM Alarm On
“OFF” =
50 PPM Alarm Off
N/A
Table 2: Menu items and values available in the Pocket CO menu.
To change the value of a particular menu item press and hold
down the button until the red light flashes. The display will then
show the new value for that item. To exit the menu repeatedly
push and release the button quickly until all menu items have
been stepped through. The display will show “EXIT” after which
Pocket CO will restart.

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3.9 Calibration:
Like many CO detectors, Pocket CO uses an electrochemical
sensor to detect carbon monoxide. The readings from this type of
sensor can drift with environment and time, resulting in inaccurate
measurements. Calibrating with a known concentration of carbon
monoxide gas allows Pocket CO to compensate for this drift, and
thus maintain good accuracy. As such:
Failing to do so may result in inaccurate measurements, and
worse, the failure of an alarm to trigger during a hazardous
situation.
A sticker underneath the battery cover indicates the date of the
next recommended calibration. Check this date every time you
change the battery, and replace this sticker if you perform a
calibration yourself.
Calibration can be performed through our mail-in calibration
service, or by ordering a home calibration kit. The home
calibration kit is safe, easy to use, and comes with simple
instructions. Information on this kit, and our mail-in service, is
available at the website:
http://www.detectcarbonmonoxide.com
Unless you are a professional, do not try to calibrate Pocket CO
using any method other than those described in the home
calibration kit.
We strongly recommend calibrating Poc et CO at least
once per year, or whenever the accura
cy of the reading is
critical.

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3.10 Additional Usage Information:
Temperature Changes:
Pocket CO may briefly display slightly higher readings of CO when
being moved quickly between extreme temperatures (such as
from a warm building into cold outside air). This higher reading
will settle back down to the actual concentration of CO within a
few minutes as Pocket CO’s temperature compensation circuit
comes into equilibrium with the new temperature.
Prolonged Exposure to Organic Vapors: If Pocket CO has
experienced prolonged exposure to organic vapors such as
fumes from paints solvents or alcohol a small amount of sensor
drift above 0 ppm may occur (even when no CO is present). If
this is observed relocate your Pocket CO to an area known to be
free of these vapors and of CO until the reading returns to
0 ppm. Depending on the length of the exposure this may take
from minutes to days. If the reading does not return to 0 ppm
within 5 days in a fresh-air environment contact KWJ Engineering
for further instructions.
If Pocket CO must frequently be used in an environment with
such vapors it is recommended that it be stored in an air-tight
container along with some activated carbon. A Pocket CO storage
container can be purchased from KWJ Engineering.

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4. Glossary of Terms
PPM: Parts per million by volume is a concentration term that
indicates that there is one part CO in one million parts air; e.g.
1 cc of CO evenly distributed in 999 999 cc of air.
T : Total Exposure: Pocket CO keeps a running sum of
concentration x time for up to the last 8 hours of
measurements. The result is a total exposure in PPM-HRS.
TWA: 8-Hour time weighted average exposure in PPM.
TWA =TE / 8 hours
MAX: Maximum CO level (PPM) measured during use.
TIM : Time (in minutes) when the maximum CO level occurred after
turning on.
RUN: Total time (in minutes) that has elapsed since turning on.
HIGH: Concentration is above maximum measurement of
500ppm.
XCD: Shown if TE has exceeded 9 999 ppm-hrs if TIME
has exceeded 9 999 minutes or if RUN has exceeded 9 999
minutes.
HOT: Temperature is more than 50
o
C (122
o
F)
COLD: Temperature is less than 0
o
C (32
o
F)
SNSR: Sensor may be malfunctioning or recovering from exposure to
very high levels of CO. If message does not go away after 1-2
hours contact KWJ Engineering.
Z RO: Apply zero gas to obtain a new zero for calibration.
GAS: Apply 100-PPM CO gas for calibration.

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5. Care and Maintenance
The Pocket CO is a high performance CO measurement device.
To maintain best performance clean it with a cloth, lightly
dampened with water. Never use soap, cleansers, alcohol,
gasoline, paint thinner, or other solvents to clean the device. Do
not submerge the device in water or any liquids. Do not refrigerate
or heat the device, or subject it to extremes of pressure. Non-
adherence to general maintenance will void the two-year
warranty.
For optimum lifetime and use, keep the device away from
extremes in temperature and humidity, and store it in a clean
place away from solvents, chemicals, disinfectants, pesticides,
and cleaners. For maximum lifetime of electronics and sensors,
store and operate in moderate environmental conditions, such as
temperatures between 40-80oF (4-27oC), RH between 40-85%,
and atmospheric pressure. It is recommended that you calibrate
your Pocket CO after each year of use in such conditions.
For highest accuracy results, or if the Pocket CO is being used in
non-standard environmental conditions (such as very dry air or
high humidity), calibration may be required at more frequent
intervals.

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6. Contact Us
By Telephone:
For technical or operational questions about Pocket CO you may
contact the Transducer Technology Division of KWJ Engineering
directly at: [phone].
For other questions or sales information you may call our toll-
free customer service line at [phone].
Both phone numbers are answered between the hours of 7:00
a.m. and 5:00 p.m. Pacific Time.
By Email:
Support: p[email protected]
Sales: [email protected]
On the Web:
http://www.kwjengineering.com
By Mail:
Transducer Technology Division
KWJ Engineering
8440 Central Ave. Suite # 2D
Newark CA 94560

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7. WARRANTY
KWJ Engineering warrants to the original purchaser that this
product shall be free from any defect in the materials or
workmanship for 2 years from the date of purchase (excluding
the battery). This warranty does not cover wear and tear due to
normal use. It does not apply to any product that has been
subjected to misuse abuse neglect accident tampering or
unauthorized repairs. KWJ Engineering may elect to replace the
unit at no extra cost with the same or a similar unit rather than
repair it.
KWJ guarantees many years of use from your Pocket CO. We also
offer a discounted replacement Pocket CO should you damage
your instrument such that it can no longer be used.
If a defect covered by this warranty should occur promptly return
the product at your expense along with a dated sales receipt
and a brief explanation of the problem to:
KWJ ngineering Inc.
Transducer Technology Division
8440 Central Ave. Suite # 2D
Newark, CA 94560