APPENDIX F: CO2 SENSORS

APPENDIX F: CO

2

SENSORS

F1.

D

ESCRIPTION OF

S

ENSORS

Three different instruments were used to measure CO

2 sensor (Figure F1) measured outdoor CO

2

concentrations. A single Bacharach comfort check

concentrations for eight hours every day of data collection.

Figure F1. Bacharach Comfort Check Sensor

Six Hobo sensors (Figure F2) were used to measure indoor CO continuously during data collection.

2

concentrations in six locations

Figure F2. HOBO CO2 Sensor

(http://www.onsetcomp.com/Products/Product_Pages/HOBO_H08/H08_family_data_loggers.html#Anchor-HOBO-

23240#Anchor-HOBO-23240).

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APPENDIX F: CO2 SENSORS

One IAQRAE sensor (Figure F3) was used to measure indoor CO

2

concentrations for a short time period

(less than 10 minutes) in six locations to compare readings with those of the Hobo. Another IAQRAE was used to measure outside CO

2

concentrations continuously.

Figure F3. IAQRAE Sensor

F2.

S TANDARD O PERATING P ROCEDURES FOR THE USE OF THE BACHARACH

The Standard Operating Procedure for the use of BACHARACH for the measurement of outside CO

2 developed from the manufacturer’s user manual.

was

TO LAUNCH THE BACHARACH:

1. Ensure temp probe is locked in place.

2. Push and hold orange button to turn on. This makes a loud beep, so try to muffle the monitor with your hands. It takes a couple of minutes to warm up.

3. Plug the IrDA interface cable into the computer.

4. Open the Plus-Com/Bacharach program.

5. The top left data box should read “Not active” with the LINK button right next to it.

6. Line up the CO2 monitor and the IrDA cable. (The sensor sight should be about 1 inch apart.)

7. Select “LINK”.

8. Check the battery status on the bottom left.

9. Check the memory status on the bottom right.

10. Check the time to make sure it matches the computer.

11. Select configure monitor from top menu. A Log frequency menu will appear. Select the

Log time that you want. (We have been logging every 5 MINUTES)

12. Hit Program.

13. Hit OK.

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APPENDIX F: CO2 SENSORS

DO THE FOLLOWING STEPS OUTSIDE AS THE MONITOR MAKES A LOUD BEEPING SOUND

WHEN YOU TURN IT ON!!!

TO BEGIN DATALOGGING:

▪ On the CO2 Monitor PRESS AND HOLD F1 until the blinking “Ө” appears on the right side of the menu screen.

▪ You are now Datalogging.

TO SAVE THE DATA:

▪ OUTSIDE of the building (because of loud beep) PRESS AND HOLD F1 for 3 SECONDS. The

“Ө” will disappear. This stores the data.

▪ DO NOT SHUT THE MONITOR OFF.

1. Attach the cord and line up the IrDA sensor with the CO2 monitor sensor.

2. Select Link.

3. Select Download.

4. Select Save.

5. At this point you have the option of where you like to save it.

6. Once you have saved the data, you must erase it from the monitor. To do this select

CLEAR. It will look like the data are still there but when you shut the monitor down and power up again it will be gone.

THIS MONITOR NEEDS TO BE CHARGED EVERY NIGHT.

F3.

S TANDARD O PERATING P ROCEDURE FOR THE USE OF HOBOS

The Standard Operating Procedure for the use of HOBOS for the measurement of inside CO

2 developed from the manufacturer’s user manual.

was

TO LAUNCH HOBO DATALOGGERS:

1. Connect GREY cord to back of computer and to the HOBO.

2. Turn on CO2 Monitor by pressing blue button.

3. Open BOXCAR 3.7 (Saved on Desktop).

4. Select LOGGER.

5. Select LAUNCH. (Launch Screen appears.)

6. Check battery status. (NOTE: This is the battery level for the HOBO ONLY).

7. Change Description ID to the appropriate MINOR ID#.

8. Change Log Interval to 1 Minute. (It should already be set at one minute, but check just in case.)

9. DESELECT “Wrap around when full”.

10. Select Start------. A warning screen will appear “UNPLUG THE LOGGER BEFORE

SELECTING OK”.

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APPENDIX F: CO2 SENSORS

TO DOWNLOAD DATA:

1. Connect cord to computer and HOBO.

2. Open BOXCAR/HOBO Program.

3. Select LOGGER.

4. Select HOBO SHUTTLE READOUT.

5. UNPLUG LOGGER BEFORE SELECTING OK.

6. A “Save As” Screen will appear.

7. HIT CANCEL.

8. Select FILE.

9. Select EXPORT.

10. Select MICROSOFT EXCEL.

11. Under Data Setting select the following Channels:

12. Temperature in Celsius

13. Humidity

14. Dew Point in Celsius

15. THE LAST VOLTAGE CHANNEL (Channel 4). It is VERY important that you select the

LAST voltage channel. This is our CO

2

Data.

16. Select EXPORT. The EXPORT screen will appear.

17. Under File Name Change this to the MINOR ID #.txt. ENSURE THAT IT IS SAVING AS A

“TXT” FILE.

18. Select the appropriate folder for saving this file.

F4.

S TANDARD O PERATING P ROCEDURE FOR THE USE OF IAQRAE

The Standard Operating Procedure for the use of IAQRAE for the measurement of CO

2 from the manufacturer’s user manual.

was developed

To Turn ON:

1. Press [MODE]. The unit will beep once and screen will display program information.

2. The monitor will display the sensor name after the monitor is turned on.

3. The IAQRAE begins the instantaneous reading of the actual gas concentrations.

4. The Instantaneous Reading function alternately displays the instantaneous reading and the sensor name.

5. The instantaneous reading is the actual gas concentration in parts per million (PPM) for CO

2

or

VOC gases; percent relative humidity (%RH) for relative humidity; and degrees Celsius (°C) or degrees Fahrenheit (°F) for temperature.

6. The monitor displays the number of minutes that the instrument has been running. To stop instantaneous readings turn off the IAQRAE.

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APPENDIX F: CO2 SENSORS

You may enter an eight-character site identification which will be included in the datalog report. To change the site identification:

1. At the “Change Site ID” screen:

2. Press [Y/+] and the display will have the current site ID: “Site ID = xxxxxxxx”.

3. Press [MODE] to move the cursor to the left most digit.

4. Press [Y/+] or [N/-] to cycle through all 26 letters and 10 numerals. Hold down [Y/+] or [N/-] for rapid scrolling.

5. Press [MODE] to advance to the next digit on the right.

6. Repeat until all 8 digits have been entered.

7. Press [MODE] to move the cursor to “SAVE?”

8. Press [Y/+] to accept the new site identification and exit the submenu.

9. Press [N/-] to discard the changes and advance to the next submenu.

10. To Turn OFF:

11. Press and hold [MODE] for 5 seconds. The monitor will beep once every second during the power-down sequence

12. The screen will flash “Off” and then go blank

NOTE: A fully charged battery pack should show 7.7 volts or higher. When the battery charge falls below 6.6 volts, a flashing “Bat” will appear as a warning message. This means, there will be approximately 20-30 minutes of operating time remaining before the monitor automatically turns off as the battery voltage falls below 6.4V.

Calibration of the IAQRAE

The IAQRAE uses a two-point calibration process with “zero” or “low Conc. Gas” as the first point of reference and a “standard higher conc. Gas” as the second point of reference. A standard reference gas

(span gas) contains a known concentration of a given gas. Zero calibration should be done before performing span calibration of sensors.

NOTE: Fresh ambient air cannot be used to zero the VOC, CO

2 presence of these components.

or RH sensors because of the background

1. The PID sensor zero should be performed using a cylinder of dry zero-VC air or nitrogen.

2. When the “Calibrate Monitor?” screen appears. Press [Y/+] to start calibration

3. If a bottle of zero air is being used, attach the calibration adapter to the gas inlet port. Connect the other end of the tube to the bottle of zero air.

4. NOTE: If a bottle of zero air is not available, place the monitor in a contaminant-free area outdoors or attach a single use zeroing tube.

5. Press [Y/+] to start zero air calibration.

6. The display will show “calibration is progress” followed by the name and reading of the CO and VOC sensors, and the messages “zeroed.”

7. The display should show a reading “0.0” or a very small number for both sensors.

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APPENDIX F: CO2 SENSORS

8. After a two-second pause, the display will show “Zero-Cal Done!” and flash sensor readings for about ten seconds before moving to the next submenu.

9. The next display will read “Multiple Sensor Calibration?”.

10. Press [N/-] to move onto the next submenu, “ingle Sensor Calibration”.

11. At the “Single Sensor Calibration” screen, press [Y/+].

12. The display shows the sensors installed in the monitor with the cursor blinking on “GO?”.

13. Press [Y/+] to select a sensor and start the calibration or press [MODE] to move to the next sensor location.

14. Turn gas flow off. Disconnect calibration tube from monitor.

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