E Instruments AQ Expert Installation instructions manual

INSTRUCTION & OPERATIONS
MANUAL
AQ EXPERT
PORTABLE MULTIFUNCTIONAL
INDOOR AIR QUALITY MONITOR
E Instruments International LLC
402 Middletown Blvd, Suite 216
Langhorne, PA, USA 19047
Phone [phone]
Fax [phone]
[email protected]
www.E-Inst.com
Distributed By:
Temperature & Process Instruments, Inc.
1767 Central Park Ave.
Suite 112
Yonkers, NY 10703
Phone: [phone]
Web Site: www.tnp-instruments.com

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TABLE OF CONTENTS
CHAPTER 1.................................................................................................................................. 3
TECHNICAL SPECIFICATIONS & SAFETY GUIDELINES.................................................. 3
CHAPTER 2.................................................................................................................................. 8
INTRODUCTION.......................................................................................................................... 8
CHAPTER 3................................................................................................................................ 12
BASIC INSTRUMENT OPERATION....................................................................................... 12
CHAPTER 4................................................................................................................................ 15
POWER REQUIREMENTS...................................................................................................... 15
CHAPTER 5................................................................................................................................ 16
SENSORS - TECHNICAL......................................................................................................... 16
CHAPTER 6................................................................................................................................ 22
AQ EXPERT SETUP................................................................................................................. 22
CHAPTER 7................................................................................................................................ 25
INTERNAL DATA STORAGE.................................................................................................. 25
CHAPTER 8................................................................................................................................ 27
WIRELESS REMOTE PRINTER............................................................................................. 27
CHAPTER 9................................................................................................................................ 29
ZERO & SPAN CALIBRATION................................................................................................ 29
CHAPTER 10.............................................................................................................................. 42
AQ GAS SOFTWARETM............................................................................................................ 42
CHAPTER 11.............................................................................................................................. 48
MAINTENANCE ......................................................................................................................... 48
CHAPTER 12.............................................................................................................................. 51
AQ EXPERT OPTIONS ............................................................................................................ 51
CHAPTER 13.............................................................................................................................. 54
BASIC TROUBLESHOOTING & REPLACEMENT PARTS................................................ 54
CHAPTER 14.............................................................................................................................. 57
VOCs IONIZATION POTENTIALS & RESPONSE FACTORS........................................... 57

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CHAPTER 1
TECHNICAL SPECIFICATIONS & SAFETY GUIDELINES
AQ EXPERT - AIR QUALITY MONITOR
1. PHYSICAL:
Material: White ABS plastic case with internal aluminum shielding
Dimensions (monitor): 11.42” X 10.24” X 4.88”
Weight: (monitor): 7.6 lbs. / 3.5 kg
Shipping Dimensions & Weight (monitor & all accessories): 15 lbs. / 7 kg
19” x 17” x 15” / 48.2 cm x 43.1 cm x 38.1 cm
2. POWER:
12 Volt, 8 AH rechargeable Li-Ion battery pack
Operating time: 6 –8 hours continuous use
110/240 VAC input, 12 V/2.5A fast charger
Charging time: 3 hours maximum
3. DISPLAY:
2.6” x 1.4” 128 x 64 graphic, chip on glass (white backlit) LCD display.
Rotating display depending on monitor case orientation
Small and large fonts, plus inverted background color for help messages
Battery condition & charger operation indicator
4. WIRELESS REMOTE PRINTER
2” high resolution, high speed, graphic thermal printer, with charger, prints:
A. current set of data
B. stored data
C. periodic data printouts
D. calibration history and external messages
5. INSTRUMENT PUMP
Continuous Air sample pump: high quality diaphragm pump with long life motor
6. STORAGE
2000 Internal memory storage tags, each tag stores one complete set of data
7. COMMUNICATIONS
Bluetooth wireless: Class 1 (100m)
USB Cable
8. SOFTWARE
AQ GAS™ Windows PC Software

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SENSORS
1. AIR QUALITY SENSORS –ELECTROCHEMICAL
SENSOR
RANGE
RES.
ACCURACY
CARBON MONOXIDE (CO)
Std Range
0 - 200 ppm
0.1 ppm
+/- 1 ppm of rdg,
+/- 0.2 ppm
CARBON MONOXIDE (CO)
High Range
0 - 2000 ppm
1 ppm
<300ppm, 10ppm
To 2000ppm, 4%
OXYGEN (O2)
Std Range
0 –25%
0.1%
0.1% Vol.
NITRIC OXIDE (NO)
Std. Range
0 - 250 ppm
0.1 ppm
+/-2 ppm of rdg
NITRIC OXIDE (NO)
High Range
0 - 2000 ppm
1 ppm
<100ppm, 5ppm
To 2000ppm, 4%
NITROGEN DIOXIDE (NO2)
Std. Range
0 - 20 ppm
0.1 ppm
+/- 0.5 ppm of rdg
NITROGEN DIOXIDE (NO2)
High Range
0 - 1000 ppm
1 ppm
<100ppm, 5ppm
To 1000ppm, 4%
SULFUR DIOXIDE (SO2)
Std. Range
0 - 20 ppm
0.1 ppm
+/- 0.5 ppm of rdg
SULFUR DIOXIDE (SO2)
High Range
0 - 2000 ppm
1 ppm
<100ppm, 5ppm
To 2000ppm, 4%
HYDROGEN SULPHIDE
(H2S)
Std. Range
0 - 100 ppm
1 ppm
+/- 4 % of rdg,
+/- 0.5 ppm
OZONE (O3)
Std. Range
0- 5 ppm
1 ppb
FORMALDEHYDE (CH2O)**
Std. Range
0- 10 ppm
1 ppb
2% ± 30 ppb
*Note: All Accuracies indicated above are under Laboratory Conditions
** This sensor may have interference from H2S, H2, CO, and other reducing gases such as alcohols
2. AIR QUALITY SENSORS –NON-DISPERSIVE INFRARED (NDIR) SENSORS
SENSOR
RANGE
RESOLUTION
ACCURACY
CARBON DIOXIDE (CO2)
Std Range
0 –5000 ppm
10 ppm
2% of Rdg. + 10 ppm
CARBON DIOXIDE (CO2)
High Range
0.0% - 20.0%
0.1%
+ 3% rdg.

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3. AIR QUALITY SENSORS –PHOTO IONIZATION DETECTOR (PID) SENSORS
SENSOR
RANGE
RESOLUTION
Min Detection
ACCURACY
VOCs
Std Range
0 –20 ppm
(0-46 mg/m3)
1 ppb
(2.3 µg/m3)
5 ppb
10% of Rdg.
+ 20 ppb
VOCs
High Range
0 –200 ppm
1 ppb
25 ppm
10% of Rdg.
+ 50 ppb
4. OTHER SENSORS
SENSOR
RANGE
RESOLUTION
ACCURACY
Temperature Type K (T1)
0 –2000 ºF
(0 –1100ºC)
0.1 ºF
(0.1 ºC)
+/- 0.5 ºC 0-100ºC
+/- 5% >100ºC
Ambient
Temperature
-40 –257 ºF
(-40 –125 ºC)
0.1 ºF
(0.1 ºC)
+/- 0.4 ºC (0-60 C)
Barometric Pressure
260 –1260 mbar
1 mbar
+/- 2 mbar
Relative Humidity
0 -100 %
0.1%
+/- 2% RH
Pressure
+/- 80 mbar
0.1 mbar
+/- 2 mbar
Air Velocity
0 –300 ft/sec
1 ft/sec

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MODEL AQ EXPERT –SAFETY GUIDELINES
This section provides general rules which must be followed for product safety, avoiding
personal injury, damage to equipment and preserving the manufacturer’s warranty.
Please take care to carefully observe the following instructions.
A. PRODUCT SAFETY INSTRUCTIONS:
➢Follow the instructions in the AQ Expert Manual
➢Do not operate the instrument outside of the parameters specified in the
technical specifications
➢Never use the instrument without the disposable fiber soot line filter or the
condensation disk filter, which are located inside the monitor connected to
the “Sample In” input. Operating the instrument without the filters will put
the monitor at high risk to damage the pump and sensors. These filters
should be replaced as needed. See maintenance chapter for filter
changing.
➢It is recommended to keep the AQ Expert horizontal using the included
swivel handle as its stand with the LCD display facing the user
➢Do not use or store the instrument together with any solvents
➢Do not block the exhaust port in the back of the instrument
➢Do not expose the monitor to extreme hot or cold temperatures outside of
the stated range in this manual
➢Do not abuse the charger cord. Do not use power cord for carrying,
pulling. Keep cord away from heat, oil, sharp edges, or moving parts.
Damaged or entangled cords can increase risk of electric shock
➢Only use the supplied, appropriate AC Charger
➢If the monitor enclosure is ever unscrewed and taken apart, avoid over-
tightening the screws that hold the two main enclosure pieces together.
➢Do not store or operate in dusty, dirty areas
➢Always use the monitor with care and use the instrument properly
➢Do not use force when disconnecting and reconnecting the Black external
Temp, RH and Pressure Sensor (see photo below)
➢Do not use instrument in the rain or high moisture areas to prevent water
droplets on the black external Temp, RH, and Pressure Sensor.
➢Remember to have the monitor checked and calibrated at least once a
year to ensure sensor accuracy and compliance with existing standards
NOTE: Please take special care when performing Span Calibration of the
monitor. You cannot revert back to the factory setting after any adjustments!
NOTE: CO2should ALWAYS be Calibrated or Zeroed with a Cylinder of ZERO
AIR. Do Not Use AQ CAL-ZF for CO2sensor calibration.

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➢DO NOT LIFT OR HANDLE THE INSTRUMENT BY THE BLACK
EXTERNAL TEMP, RH, PRESSURE SENSOR HOUSING! See photo
below
B. ELECTROMAGNETIC COMPATIBLITY
Complies with EN61326-1, Portable Equipment
The E Instruments AQ EXPERT Indoor Air Quality Monitor is a battery operated
Portable device designed to be used by a qualified engineer/technician to make
measurements in buildings and residential facilities. For long-term testing, you may
operate the unit connected to the supplied charger by carefully following the product
safety instructions in Section A above.
C. ESD Protection
In extreme cases or abnormal applications, Electrostatic Discharge can
potentially cause serious and immediate damage to the electronic circuits of the
instrument.
D. BATTERY DISPOSAL & RECYCLING
Recycle all applicable material properly. Take faulty/depleted batteries to
proper collection/recycling centers
Dispose of batteries and the monitor according to statutory regulations.
Do not dispose of with regular household items. After the monitor’s useful
life, please return to your local authorized E Instruments’ distributor or
send back to E Instruments directly. We will ensure that it is disposed of
in an environmentally friendly manner

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CHAPTER 2
INTRODUCTION
A. UNPACKING THE INSTRUMENT
Every E INSTRUMENTS AQ EXPERT includes as standard equipment:
•IAQ Monitor Model AQ Expert with CO2, Temp, %RH, DPt, WBT, BP, Velocity,
Differential Pressure and Differential Temperature
•Internal Continuous Sampling Pump
•Swivel Handle
•Battery charger / AC adaptor for the monitor
•USB Thumb Drive includes:
•AQ GAS TM Software for Windows TM
•Instruction Manual
•USB Cable for Software Kit
•Internal Wireless Bluetooth
•Bluetooth Dongle for PC
•Calibration Certificate
The instrument can have up to six (6) electrochemical gas sensors, one (1) infrared gas
sensors and one (1) PID sensor installed. The AQ Expert has three temperature
sensors in total. All sensor readings are single range readings with ranges listed in
Chapter 1.

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B. INSTALLING/REMOVAL OF SWIVEL HANDLE INSTRUCTIONS
1. Depress BOTH of the Grey Push-Release buttons on the Left & Right circular
ends of the handle (Photo B)
2. With the handle angled AWAY from the front face of the instrument and with the
buttons depressed, position the circular ends OVER the Gray circular holders ON
the side of the instrument until it falls into place (Photos C & D)
3. Depress the Grey Push-Release buttons and rotate the Handle down below the
Front Face (Photo E) of the instrument until it locks into place under the
instrument holding it upright in place. (Photo F)
4. To Remove the handle, repeat steps 1-3 in reverse
PHOTO A PHOTO B PHOTO C
PHOTO D PHOTO E PHOTO F
C. REPACKING UNIT IN OPTIONAL VINYL CARRYING CASE
1. With the AQ Expert powered OFF, turn the instrument on its side with the
FRONT FACE of the unit to the LEFT. See photo A below.
2. Place the carrying case on a supported surface (desk, floor, etc) with the Front
Logo facing the user.
3. With the AQ Expert powered OFF, turn the instrument on its side with the
FRONT FACE of the unit to the LEFT. See photo A below.
4. Carefully place the AQ Expert in the Case, taking SPECIAL PRECAUTION to
NOT damage the External Temp, RH, Pressure sensor. See Photo B below

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PHOTO A PHOTO B
INSTRUCTIONS: DO NOT LIFT OR HANDLE THE INSTRUMENT BY THE BLACK
EXTERNAL TEMP, RH, PRESSURE SENSOR HOUSING!
D. AQ EXPERT STARTING INSTRUCTIONS
1. Make sure the instrument is in a clean-air, room-temperature environment and
turn it on by pressing the POWER key on the keypad. The instrument will begin
to draw in air from the SAMPLE IN inlet at a rate of about 500 cc/minute.
2. If needed or in doubt of the contaminants in the Ambient Air, you can initiate the
ZERO CAL on ALL of the GAS sensors on the AQ Expert. Please refer to
CHAPTER 8 of this manual for ZERO & SPAN calibration on the AQ Expert.
3. Press the MEASURE key to view the ambient temperature, barometric pressure,
relative humidity and dew point. The toxic gas readings are also displayed: CO,
CO2, NO, NO2, SO2, H2S, O3, & VOCs.
4. If, at the end of the ZERO countdown, if the display shows an error message for
a particular sensor, see the troubleshooting table in section D of this chapter. The
instrument will measure correctly all sensors that do not show an error message.

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LIST OF ABBREVIATIONS
PARAMETERS
CO2Carbon Dioxide
CO Carbon Monoxide
Ta Ambient (room) Air Temperature
RH Percentage of Relative Humidity
DPt Dew Point Temperature
WBT Wet Bulb Temperature
BP Barometric Pressure
O2 Oxygen
O3 Ozone
VOCs Volatile Organic Compounds
FMH Formaldehyde
H2SHydrogen Sulfide
NO Nitric Oxide
NO2Nitrogen Dioxide
SO2Sulfur Dioxide
VEL Air / Gas Velocity (measurement with pitot tube)
∆P Differential Pressure (with Velocity Probe turned OFF)
T1 Thermocouple Type K Temperature (T1 Input)
T2 Thermocouple Type K Temperature (T2 Input)
BAT Battery Life / Voltage
NA Parameter Not Available
UNITS
PPM Parts (of pollutant) per million
PPB Parts (of pollutant) per billion
mg/m3 Milligrams per Cubic meter
µg/m3Micrograms per Cubic meter
°F Temperature Measurement in Fahrenheit
°C Temperature Measurement in Celsius
"WC Inches of water (pressure measurement)
mmHg Millimeters of Mercury (pressure measurement)
"Hg Inches of Mercury (pressure measurement)
PSI Pounds per Square Inch (pressure measurement)
mmWC Millimeters of water (pressure measurement)
kPa KiloPascals (pressure measurement)
mbar Millibars (pressure measurement)
FPS Feet per second (gas / air velocity measurement)
MPS Meters per second (gas / air velocity measurement)
CFM Cubic feet per minute (gas / air velocity measurement)
V Voltage (battery)
NOTE: MGM (milligrams per cubic meter) units are calculated and displayed for 20C
and 1 atm conditions per US EPA standards.

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CHAPTER 3
BASIC INSTRUMENT OPERATION
The AQ EXPERT is operated by the 11 button keyboard located on the front of the
monitor.
•The POWER key turns the instrument on and off.
•The MEASURE key shows the currently measured parameters.
Displays the monitor’s currently measured data in either of two (2) fonts:
A. Small fonts (all data displayed simultaneously plus range indicated, battery
condition and time)
B. Large fonts (four data parameters displayed simultaneously)
Note: The AQ Expert allows the user to ZOOM in and out of the screen by changing
from Small to Large Fonts using the MEASURE key.
•Four keys will bring up a menu: SETUP, CALIB, STORE, & PRINT.
SETUP
Controls all customization parameters, such as measurement
units, for the monitor
CALIB
Controls calibration settings and zeroing of the monitor’s
sensors.
STORE
Controls operation of the monitor’s internal data storage
PRINT
Executes print commands for the monitor’s optional remote
Bluetooth printer
•The menus are navigated with the UP, DOWN, LEFT, RIGHT, & OK keys.

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INSTRUMENT OPERATION OVERVIEW
1. Turn the AQ Expert on by pressing the POWER key. The instrument’s internal
pump will immediately turn on and the E INSTRUMENTS logo will appear.
2. If applicable, attach the optional probe and sampling line to the monitor.
3. Press the MEASURE key and check the unit’s battery condition.
The MEASURE key allows the user to toggle between a small
font and a large font screen. Select the small font screen.
The battery icon is displayed in the middle of the bottom line of
the display. Its condition is marked by the shaded fraction of the
icon. If the unit is powered by the battery charger a small “plug”
icon will replace the battery icon.
NOTE: When connecting the battery charger to the monitor
make sure that the “plug” icon appears on the MEASURE screen.
This ensures a proper power connection and charging of the
batteries.
4. If you are using the monitor for the first time, press the
SETUP key to set the appropriate parameters (i.e.: measurement units) for your
application. See Chapter 5 for an explanation of each parameter.
5. All sensor readings shown on the screen indicate Ambient measurements. To
ZERO the gas sensors, please see Maintenance Chapter 11 of this manual.
6. To obtain a printout of the data displayed, press the PRINT key. The cursor
(reverse color) will point to:
Print Test Record
CO2: 520PPM O2: 20.9%
CO: 0PPM NO2: 0PPM
Ta: 79.1°F SO2: 0PPM
RH: 46.9% H2S: 0PPM
DPt:57.0°F O3: 0PPB
BP: 1012mb VOC: 0PPB
_____________________
Sampling 12:45:00
NOTE: Depending on the options
enabled for your AQ EXPERT some of
the entries in one or more of the
displays shown above will be blank if
that option is not available.
APR 1 ‘14 12:45:00
Temperature Units: F
Measure Units: PPM
Pressure Units: inWC
Pumps: AUTO 1000cc/m
Velocity Probe: OFF
Velocity Units: FPS
Duct Size: 0 in2
Display Contrast: 24
Baudrate: 115 kbps
Version: 1.00Li
Fast-Charge Mode
Battery Charger Connected
Battery Empty
Battery Full

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Press the OK key to execute a printout on the AQ Expert’s optional remote
printer.
7. Measured data can be stored in the monitor’s internal memory. Please refer to
Chapter 7 for more details about data storage.
8. When you are finished with your measurements allow the monitor to draw clean
ambient air for several minutes before turning the monitor off. If you are using
the optional probe, please disconnect and let the instrument run in clean ambient
air before turning the instrument off.

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CHAPTER 4
POWER REQUIREMENTS
The AQ Expert can run off of AC power or the internal Li-Ion rechargeable battery pack.
It is recommended to run the AQ Expert off AC power as often as possible for maximum
operating time.
Power is supplied by a Li-Ion rechargeable battery pack. The battery pack will supply
power to the monitor for approximately 6-8 hours of continuous operation.
A 110 –240 Volt AC charger having a 12 Volt DC / 2.5A output is supplied with the
instrument. The battery charger will fully charge the battery pack in three hours.
You can check the condition of the batteries at any time:
1. By pressing the MEASURE key, (small font screen) and observing the battery
icon, located at the bottom of the display.
2. 2. By pressing the MEASURE key, (large font screen), the user can scroll all the
way to the end using the DOWN arrow key to observe the battery life shown in
voltage. When the unit is operating on its internal batteries, the voltage
displayed will vary from an initial 8.0 to 8.4 volts (fully charged) dropping slowly to
approximately 7 volts (batteries nearly empty). When the battery voltage drops to
7.1 volts a “low battery” warning will appear on the display. Within a few minutes
later the instrument will automatically turn off, to preserve the remaining battery
power for the sensor bias voltages.
Battery Charger Connected
Battery Full
Battery Empty
Fast-Charge Mode

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CHAPTER 5
SENSORS - TECHNICAL
The great versatility of the AQ Expert Air Quality monitor is partly due to the large
number of sensors available within a single monitor.
These sensors are primarily gas sensors and can be grouped into four categories based
on their principle of operation:
1. Six (6) electrochemical gas sensors*
2. One (1) NDIR (infrared gas sensors) –CO2
3. One (1) Photo ionization detector (PID gas sensor) - VOC
4. Non-gas sensors (Temperature, Velocity, Humidity, Pressure, and
Barometric pressure) sensors
*NOTE: When O3(Ozone) sensor is installed the AQ Expert can include O3+ NO2OR
O3+ SO2. The unit can NOT have all three (3) sensors (O3+ NO2+ SO2)
together simulatenously.
The main section of the monitor that houses all the electrochemical, NDIR, and PID gas
sensors, battery pack, and PC board. On the face of the unit, the external sampling
system or Ambient Temperature, Relative Humidity, and Barometric Pressure.
The figure below shows the location of the gas sensors on their housing:
SENSOR
LIST:
CO2
CO
VOCs
NO
NO2
SO2
H2S
CH2O
O2
O3

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1. ELECTROCHEMICAL SENSORS
All electrochemical sensors are mounted on bayonet style fittings for easy removal.
The electrochemical sensors are described below:
A. Nitrogen Dioxide sensor (NO2)
This is a three electrode sensor that responds to nitrogen dioxide gas. Nitrogen dioxide
is a “sticky” gas and this sensor’s response is usually the slowest of all sensors.
B. Sulfur Dioxide sensor (SO2)
It is a three electrode sensor that responds to sulfur dioxide gas. It is equipped with an
inboard filter to remove interference from H2S gas and other acidic gases.
C. Nitric Oxide sensor (NO sensor)
This is also a three electrode sensor that responds to nitric oxide. It is equipped with an
inboard filter to remove any interference from other acidic gases.
The nitric oxide sensor requires a constant bias-voltage for proper operation. This is
supplied by the monitor’s battery. If the battery voltage drops below a certain value, the
monitor will turn off automatically to maintain the sensor bias. If, however, the battery
voltage further drops to near zero, one must wait 24 hours after connecting the battery
charger, for the sensor bias to recover.
D. Oxygen sensor (O2sensor)
This sensor measures the oxygen concentration in the sample. It is a two-electrode
electrochemical cell. It has a silver cathode and a lead anode. Oxygen diffuses through
a tiny hole and reacts with the lead anode. The reaction produces an electric current.
The unit software linearizes the current vs. oxygen response. The cell becomes
exhausted when all the lead is consumed.

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E. Hydrogen Sulfide sensor. (H2S)
This is a 4-series three-electrode micro sensor with low methanol interference. It
measures the concentration of hydrogen sulfide, which is a highly toxic gas. Special
precautions must be taken during calibration.
F. Carbon Monoxide sensor (CO)
This is also a three electrode sensor that responds to carbon monoxide. It is equipped
with an inboard filter to remove any interference from other acidic gases.
The optional High Range CO sensor has four electrodes. One measures the
concentration of carbon monoxide gas and the other the concentration of any interfering
hydrogen gas (It is hydrogen compensated).
G. Ozone sensor (O3)
This is also a three electrode sensor that responds to ozone.
H. Formaldehyde Sensor (CH2O)
This is also a three electrode sensor that responds to formaldehyde. It is equipped with
an inboard filter to remove any interference from other acidic gases.
This sensor may have interference from H2S, H2, CO, and other reducing gases such as
alcohols. In applications where the user is measuring both H2S and Formaldehyde, the
Formaldehyde readings could be inaccurate as the levels of H2S increase. Relative
measurements could be appropriate in these situations.
2. NDIR (INFRARED) SENSOR (CO2)
A non-dispersive infrared (or NDIR) sensor is a simple spectroscopic device most
commonly used to measure CO2in indoor air quality applications. The main
components are an infrared source (lamp), a sample chamber or light tube, a
wavelength sample chamber, and the CO2gas concentration is measured electro-
optically by its absorption of a specific wavelength in the infrared (IR).

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The AQ Expert Air Quality Monitor is equipped with one standard NDIR infrared sensor
capable of CO2measurement (standard range: 0 –5000 ppm). This infrared sensor
can be substituted for higher CO2ranges upon special request.
The NDIR options have the following specifications:
GAS
RANGE
ACCURACY
CARBON DIOXIDE
(CO2)
0 –5000 ppm
2% of reading
+ 10 ppm
CARBON DIOXIDE
(CO2)
0.0% - 20.0%
3% of reading
3. PHOTO IONIZATION DETECTOR (PID) - VOCs
Photo ionization detectors are the most common method to measure volatile organic
compounds (VOCs) and other gases in indoor air quality in concentrations in parts per
billion (PPB) and parts per million (PPM).

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The PID options have the following specifications:
GAS
RANGE
ACCURACY
VOCs*
0 –20 ppm
+ 10 % of reading
VOCs*
0 –200 ppm
+ 10 % of reading
*VOC sensor will not measure Formaldehyde. The ionization potential of the sensor is outside of the VOC sensor
range. If you need Formaldehyde, you need to use the direct CH2O sensor.
4. NON-GAS SENSORS
A. Ambient Temperature sensor
This is a solid state sensor located on the front panel of the monitor. The
ambient temperature is displayed on the MEASURE screen in either °F or °C.
The dew point is calculated from the ambient temperature and relative humidity.
The dew point is displayed on the Small and Large Font MEASURE screens as
DPt.
B. Humidity sensor
This is a solid state sensor located on the front panel of the monitor. The
relative humidity is displayed on the MEASURE screen in %RH (% Relative
Humidity). The Wet Bulb is calculated from the ambient temperature, relative
humidity, and barometric pressure. The wet bulb is displayed on the Large
Font MEASURE screen only as WBT.
C. Barometric Pressure sensor
This is a solid state sensor located at the front panel of the monitor. The
barometric pressure is displayed on the Small and Large Font MEASURE
screens as BP.
D. External Temperature Sensor (T1 & T2)
The thermocouple is located at the tip of any optional or separate Type K
thermocouple probe and/or wire. The T1 & T2 temperature measurements are
displayed on the Large Font MEASURE screen only as T1, T2.
E. Differential Pressure / Air Velocity sensor.
If the monitor comes with the Differential Pressure option and/or the air velocity
option (optional separate S-type pitot tube and pressure tubing), the internal
pressure sensor is a very low range pressure sensor. The Velocity