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  • Author Author: abhishek2018
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Study on Residential Carbon Monoxide Pollution

abhishek2018

Table of contents

RoadTest: Enroll to Review the Multicomp Pro MP780892 Air Quality Meter

Author: abhishek2018

Creation date:

Evaluation Type: Test Equipment

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Molex KIT-INS-CO-03 ,Molex INS-CO-03,EXTECH INSTRUMENTS CO260,MOLEX KIT-INS-CO-02

What were the biggest problems encountered?: 1) Some readings were stubborn, unless the meter is placed more nearer, the recorded reading becomes lesser or zero. For example, I burnt 0.3cm with soaked lubricant, but it recorded zero unless brought too near or above in the air. Bringing too near the fire will damage the nozzle.

Detailed Review:

Thanks for choosing me to review and evaluate the portable air quality meter,  Carbon Monoxide detector/meter, MP780892 by MultiComp PRO. The title of my review is same as the submitted title of the proposal.

I have divided this review in 7 parts (mentioned in Table of Contents) and videos in 6 parts.  

To make one understand about this product/CO detector/testing instrument, I have divided video recording's in 6 parts, which are summarised as 

  1. Video : Alarm Setting
  2. Video Backlight1, is demonstration of backlight when room light or ambient light available.
  3. Video Backlight2 is second demonstration of backlight  when NO room light or NO ambient light available.
  4. Video : set_tr.mp4 is on demonstration of  Set + Exclamation with Red triangle.
  5. Video : Damage of nozzle after 24 readings.
  6. 24 Short videos of Measurement Recordings ( Except these recordings all the above are posted both on this review page and YouTube. Youtube uploading is not for my self promotion.)

Table of Contents

  1. Unboxing The MultiComp PRO Air Quality Meter, MP780892
  2. Measurement Recordings & Conclusion
    1. MatchStick Experiments
    2. Cloth Experiments
    3. Short-Circuit Experiments
    4. Cotton Experiments
    5. CNG BS IV Vehicle Emission Experiments
    6. Petrol 2 wheeler
    7. Candle Burning and Wax Experiments
    8. Paper Experiments
    9. Misc Experiments
  3. Future Research Work
  4. Meter Handling Feedback : Pros and Cons
    1. Pros
    2. Cons
    3. Precautions/Safety Warnings
  5. Comparable Products
    1. Molex KIT-INS-CO-03
    2. Molex INS-CO-03
    3. EXTECH INSTRUMENTS CO260
    4. MOLEX KIT-INS-CO-02
  6. Add-On
  7. Conclusion

1. Unboxing The MultiComp PRO Air Quality Meter, MP780892

Following are the unboxing pictures :

(a) All items together (in packing)

(b) Invoice

(c) Meter with batteries and inside manual and Silica gel packet

(d) Type of Batteries Provided : Four AAA (or 24A LR03) 1.5 V, 12 Amperes

Video  :  Due to been not well, I cannot record voice as needed in this road test and I m sorry for this but rest all I have reviewed properly according to me (except voice recording video).  

2. Measurement Recordings & Conclusion

I have taken number of recordings under different conditions. Now, what experiment was performed, it is mentioned in the video description, which are uploaded on youtube.  24 Recording Videos will look here cumbersome and bulky and would occupy lot space on this review page.  I m mentioning the summary and conclusion of it here (one may not go on youtube, unless one doubts the measurement).

I had planned to take more readings like from ill patients with lung disease/infections, smoking people, some industrial locations but unfortunately I could not record them as I failed to get approval because of these reasons :

  • The inhaled and the exhaled smoke from cigarettes etc from people or patients reveal face or part of face. Moreover, proper study required couple of days with repeated recordings on which no one got agree (atleast during this study period).
  • Some got worried if the reading if found is subjected to some penalty or unnecessary litigation trouble.
  • Few wanted compensation.

I have concluded that 'one recorded reading' is not applicable universally and hence the measurement recordings must not be taken directly as conclusion. The same object do not give the same reading under different environmental conditions, and the other vendor or product made of different material do not give the same reading as the other. Following observations were found during more readings than the uploaded 24 recordings

(i) MatchStick Experiments 

  • Carbon Monoxide Reading 1 showed reading of 111 ppm when 1 matchstick is burnt to 85% of its length and the other half matchstick which was burnt caught fire to only 10% of its length. Environment condition was closed indoor
  • Carbon Monoxide Reading 18 showed reading of 1626 ppm when 2 matchsticks (with its powder) are burnt. Environment condition - open atmosphere. And matchsticks are of different vendor and old matchsticks.
  • Carbon Monoxide Reading 19 showed reading of 200 ppm when 4-6 matchsticks (with its powder) are burnt. Environment condition - open atmosphere. Despite more quantity, these show reading only upto 200 ppm and this is because earlier one was of different vendor and were old matchsticks.
  • Carbon Monoxide Reading 20 showed reading of 0 ppm (no reading) when all already used/burnt matchsticks (with no powder) are burnt. Environment condition - open atmosphere.

(ii) Cloth  Experiments 

  • Carbon Monoxide Reading 2 shows reading of 1618 ppm  when only 0.3 cm - 0.45 cm of cloth edge which was used in car gear oil servicing was burnt. This was only edge and it was not soaked in oil, just minute quantity of oil. Recording has been taken from start where it reached 1618 ppm and then back to 0 ppm. The whole time duration is 9 min 36 seconds.
  • Carbon Monoxide Reading 3 shows reading of 3 ppm at 0:15 of the recording. The max. reading of 1640 ppm displayed is from the earlier's experiment. Same cloth of 'Carbon Monoxide Reading 2' is burnt to see if it is burnt in pure form. Size is even same 0.3 cm - 0.45 cm of cloth edge. 
  • Carbon Monoxide Reading 12 shows reading of 232 ppm when a dirty cloth piece which has oil spot from car service gear oil cleaning is burnt.
  • Carbon Monoxide Reading 13 shows reading of 923 ppm when the same clean unused piece of cloth of 'Carbon Monoxide Reading 12' is burnt.
  • Carbon Monoxide Reading 15 shows reading of 306 ppm at 0:49 of the recording. The max. reading of 1595 ppm displayed is not from this experiment.  A small cloth piece burnt.
  • Carbon Monoxide Reading 16 shows reading of 1595 ppm when again a small cloth piece is burnt.
  • Carbon Monoxide Reading 17 shows reading of 0 ppm when a small piece of black cloth intentionally soaked with mustard oil is burnt. In the video, I have shown a red cap which has mustard oil and is used to soak cloth. It is surprising, reading was 0 ppm.

(iii) Short-Circuit Experiments 

  • Carbon Monoxide Reading 5 shows reading of 1640 ppm. Experiment - intentional short-circuit on wires which are connection from battery to 50Hz  230VAC mains MCB. The intentional simultaneous short-circuit was done on wires insulation and 2 thick insulation and 2 smaller dimension insulations caught fire. Some SMD components caught fire.
  • Carbon Monoxide Reading 6 shows reading of 112 ppm. Experiment - intentional short-circuit on insulation of Solar DC-DC converter.

But in general, when only an insulated wire or alone insulation was burnt (not shown here), it only shows rubber burning smell and may be release of other gases but meter read it as 0 ppm (always) and so, not carbon monoxide. But, the common short-circuits which are heard in news, I have not taken measurement at those places.

(iv) Cotton Experiments

(v)  CNG BS IV Vehicle Emission Experiments

A.) Following three readings are at the same time, just minutes apart. The reading is from 4 stroke, CNG, 998 cc, 4 wheeler. The vehicle in idle neutral, no acceleration. The environment condition was raining and the vehicle condition was it was not used for 15-20 days and was parked. 

B.) When the same vehicle used regularly and when it was subjected to measure, it showed 0 ppm and the environment condition was clean, sunny.

(vi) Petrol 2 wheeler

  • Carbon Monoxide Reading 7 shows reading of 1601 ppm. Reading of 13 seconds from 2 stroke 100 cc 2 wheeler. In 13 seconds, it gave reading which I was not expecting. The vehicle in idle neutral, no acceleration.

(vii) Candle Burning and Wax Experiments

  • Carbon Monoxide Reading 4 shows reading of 13 ppm during candle burning and little wax. It was strange as when other candle wax was intentionally tried to be melted with the burning one, reading was 0 ppm. But when the flame of the burning candle was placed near this wax initially, it showed this reading.

(viii) Paper Experiments

(ix) Misc Experiments

  • Carbon Monoxide Reading 21  shows reading of 9 ppm. Burning of liquid medicine measurement plastic cap. Max. reading 9 ppm
  • Breathing : I am non-smoker and tried different patterns and it was always 0 ppm but only once when it showed 1 ppm! out of 60-70 readings. This particular one is not claim but it instigates research with ill patients and/or with smokers.

3. Future Research Work

The use of this CO detector/testing instrument, The MultiComp PRO Air Quality Meter, MP780892  do not end with this review. The CO detector/instrument is a necessary test tool in many environmental scenarios. 

I have written one research paper which is basically the summarization of this article only and is incomplete (the funding of this CO detector/testing instrument/testing equipment has been acknowledged in this Research paper). 

I have revealed one of the instigation factors to do research with ill patients or smokers.

The CO detector/testing instrument has certainly proved to be useful in refining my personal scientific/clinical models, which hopefully would be submitted in the coming months and I will even mention the use of this meter explaining how it strengthens justification. One may track on my profile or I will even mention them in the comment box (hopefully this do not make me accuse of self publicity).

4. Meter Handling Feedback : Pros and Cons

Following are pros and cons (not mentioned according to priority)

Pros 

1. CO Range 

Though, the company's manual says CO range is 0 ppm to 1000 ppm with a resolution of 1 ppm and accuracy of ± 5% ( or 5 ppm), which makes the maximum range to 1050 ppm but as demonstrated in the videos, the MultiComp PRO MP780892 easily measures upto 1640 ppm.


2. Warm-up & Response time 

The response time of the reading, which technically is 90 % of the reading is within 1 second, which is too good and indicates that the warm-up time is within approx 0.70 seconds.

Note : The warm-up time of  0.70 seconds (approx) is not indicated by the manufacturer but calculated by me. The manual only mentions T90 < 60s.


3. Adjustable Alarm

If one goes for the settings, the alarm of MultiComp PRO MP780892 can be quite complicated for novices, otherwise it is simple.  The alarm can be changed with long press, short press and there are 2 setting points - A1 and A2.

3.1 Setting 1, A1

This is the low alarm point and the default setting is 35 ppm. This can be adjusted manually if one wants to 20 ppm or lower. One can question when the ASHRAE Standard 62-1989 for living areas is 9 ppm, why 35 ppm is chosen, not 30 ppm.The MultiComp PRO MP780892 has not chosen this 35 ppm as the low alarm point arbitrarily. This 35 ppm is the time-weighted average (TWA) and is the permissible limit for carbon monoxide in working environment.

When the meter reads CO level at this default setting A1 or the user adjusted A1 setting, the buzzer sounds  and the light will flash at the frequency of 1 Hz.

If one do not want to hear buzzer sound, the user can press [MUTE] button to stop the audible alarm. The buzzer will stop working temporarily and the icon in the upper left corner of LCD will disappear, for 3 minutes only but after 3 minutes the buzzer will again sound and icon will again flash at the frequency of 1 Hz. This is again a good setting in case user forget and neglects CO presence which can harm him/her or by chance the child plays and the setting is OFF.

Caution : Wrong ppm setting can lead to potential danger.

3.2 Setting 2, A2

The setting 2 is  A2 and is set at 200 ppm by default.  One can set this to 500 ppm or 50ppm or 800ppm. One can again question, when the  carbon monoxide reading of 200 ppm causes carbon monoxide poisoning with known symptoms of mild headache, fatigue, nausea and dizziness within 2-3 hours, why not 200 ppm is set. Again this 200 ppm value, the MultiComp PRO MP780892 has not chosen arbitrarily,it is TWA Short-term exposure limit (STEL) value.

When the meter reads CO level at this default setting A2 or the user adjusted A2 setting, the buzzer sounds  and the light will flash at the frequency of 2 Hz.

If one do not want to hear buzzer sound, the user can press [MUTE] button to stop the audible alarm. The buzzer will stop working temporarily and the icon in the upper left corner of LCD will disappear, for 3 minutes only but after 3 minutes the buzzer will again sound and icon will again flash at the frequency of 2 Hz. This is again a good setting if by chance the child plays and the setting is OFF or in case user forgets and neglects high CO presence which can hospitalise or cause death or cause other symptoms. 

Caution : Wrong ppm setting can lead to potential danger.

3.3 Video : Alarm Setting

  1. I have pressed, long press [HOLD] button, one can see, A1 is 35ppm default;  then I long pressed [SET], one can see 'S-1', this S-1 is to save the reading desired; then I pressed power button  to EXIT settings. 
  2. Then I again entered and pressed [TEMP] button, not to view temperature but to [UP] the counter of A1 and one can see it changed to 36 ...  
  3. Then I pressed [BL] button, not to turn ON/OFF backlight but to [DOWN] the counter of A1 and one can see it changed to  38  ... to  35. 
  4. I didn't saved any setting, so when I again turned on after exiting, it is 35 ppm only.
  5. Then I turned on meter, and  long press [HOLD] button, one can see, A1  35; then I pressed [SET] button , one can see A2 200; then I again pressed [SET] button , one can see TWA 035 ; then I again pressed [SET] button , one can see STEL 200 ; 
  6. Now, I increased counter by pressing [TEMP] button and increased from 35 to 43 and saved by long pressing [SET], one can see 'S-1'. Then I exit from the setting and turn OFF meter and then turn ON, one can see now default is 43 ppm instead 35 ppm, I changed back to default 35 ppm.
  7. Similarly, one can change A2 200 ppm setting. But this time instead A1, repeat the processes on A2.


4. Back-light Control

The manual says if the light is insufficient in the environment, the backlight can be used to read reading. The backlight can be turned on or off by pressing [BL] button.

I have made two videos on this to see backlight [BL] ON/OFF effect.

4.1 Video Backlight1

Video backlight1 (5466.bl_1.mp4) demostrates backlight [BL] when room light or ambient light available. Initially, no backlight [BL] used and one  can read the display but 0:05 of this recording, the backlight is ON and the backlight is not eye-irritating in the ambient light. 

4.2  Video Backlight2

Video Backlight2 (5238.night.mp4) demostrates backlight [BL] when NO room light or NO ambient light available. One can clearly see the backlight effect in dark night and it is amazing as one can clearly read the reading. FOllowing are the video phases

  • Initially the video is taken with only meter on and with camera light/torch but NO room light or NO ambient light.
  • Then at 0:04 of the recording, backligh[BL] is turned ON and camera light/torch is ON;
  • at 0:12, camera light/torch is turned OFF but only backlight[BL] is ON, one can see meter's bottom view is not visible due to dark but display is visible and can be read due to backlight.
  • at 0:22, camera light/torch is OFF and backlight[BL] is OFF, and remained OFF till 0:34.
  • at 0:35, camera light/torch is  OFF but again only backlight[BL] is ON, till the end of video.

5. Sensor Temperature

As one will use the CO detector/testing instrument where some form of combustion is happening, one cannot be sure if the reading is increasing temperature of the sensor itself.  Anytime, one can read the internal sensor temperature by pressing [TEMP] button. This may or may be not ambient temperature. This temperature value is for the temperature compensation of the sensor detection result. By pressing  [TEMP] button, sensor temperature  is displayed in Celsius, °C, and again pressing  [TEMP] button, sensor temperature gets displayed in Fahrenheit, °F.


6.  Auto power off
The CO detector/testing instrument automatically shut down in case of no operation or alarm action within about 20min.


7. Battery Strength Indication
The CO detector/testing instrument requires four batteries of type AAA (or 24A LR03) 1.5 V, 12 Amperes, which are provided with the pack. The batteries have to be changed if the battery icon on the upper right corner (shown below) flashes.


8.  Weight
The CO detector/testing instrument dimensions are 197mm × 55mm × 37mm weighing 1.4 kg  or 3.08647 pounds (lbs)  or 49.3835 ounces.


9. Calibration of Sensor
The electrochemical gas sensor is self calibrated.
The manual mention 2 keys to be simultaneously pressed in order to calibrate sensor. 
a) Key 1 is Set + Exclamation with Red triangle. This is only demonstrated in the following video.

2) Key 2 : Set + Power button. In this, I wont go as this calibration procedure requires usage of carbon monoxide (poisonous gas).

10. Sensor Self-Test

The actual sensor calibration is complicated which can be done by professional trained with handling carbon monoxide gas. But this instrument/product allows user to perform its self-test, which can be done regularly once a month or once every 24 hours but not frequently.

For this, one should press only [SET] button and the sensor performs its self-test in 3 minutes. If the sensor is broken or wire breakage or short circuit, FAULT icon will flash in the upper right corner of LCD.

If the case of fault detection of the sensor, FAULT icon flashes during normal gas detection. In such case, one will have to calibrate the sensor and contact company professional.

One need not fear if sensor has low life-span, the faults like sensor broken or wire breakage or short circuit can be caused by meter falling or too high temperatures but as such the sensor has life expectancy of 5 years.

11. Product Working Principle

This CO detector/testing instrument uses Electro-chemical CO gas sensor cell and takes reading based on the sampling method of diffusion and dispersion. 

The carbon monoxide poisoning level as given in the manual 

12. Usually to measure and detect stationary CO, multiple such instruments are needed (by guidelines), this product substantially reduces cost allowing immediate detection. 

13. There is holder/clipper in the rear, which can be used to keep in pocket (without fearing losing meter during at the time of carrying).

14. LCD Display 
The LCD display is approximately 4 cm x 3 cm with additional 1 cm (approx) in the logo, that is 4 cm x 4 cm but in this  4 cm x 3 cm , 20 icons very well and without mess gets displayed and are understandable by user.

15. Certifications
This CO detector/testing instrument is CE and CMC qualified, and RoHS (Restriction of Hazardous Substances ) complaint and certified.  This product is RoHS Compliant by Exemption (Y-Ex) but RoHS Phthalates Compliant. 
There is no SVHC (Substances of Very High Concern).

16.  Export Control Classification Number (ECCN)

The 6-digit HSN (Harmonized System of Nomenclature) code is  85366990, EU Export Control Classification Number is NLR  and the US Export Control Classification Number is EAR99.  


Cons 

1. The nozzle covering though of plastic is of nominal quality as even when the intentional burning of the cloth with gearoil is done, it doesn't get melted fully but minor damages can be seen.

Some readings were stubborn, unless the meter is placed more nearer, the recorded reading  becomes lesser or zero. For example, I burnt 0.3cm with soaked lubricant, but it recorded zero unless brought too near or above in the air. Bringing too near the fire will damage the nozzle and in few cases it was necessary to bring it near otherwise reading cannot be recorded as it showed 0 ppm.

Caution : This doesn't mean one can take reading by putting in fire or take reading touching the fire. If this is done, plastic will melt fully damaging the sensor. In the videos, it might look it is in fire but there is negligible(very little) distance between fire and the meter, may be at times minor touch had happened.

Video : Damage of nozzle after 24 readings.

2.  High Fire or bigger fire cannot be tested easily due to risk of melting which may completely damage the electrochemical gas sensor.

3. Sensor Calibration

The sensor has to be calibrated but it is as such not a cons, any meter needs calibration after some time.

4. The manual states this - CO detector/testing instrument is not suitable to detect carbon monoxide concentration in the environment with frequently or drastically changed temperature and humidity. 

5. Battery Placement Confusion 

It is obvious that batteries would be put in the rear of the CO detector/testing instrument but there are three screws which creates confusion which to open. The manual does mention 'battery cover' and it may not be understood by novices.

After unscrewing the circled one

Moreover, improperly placing back the cover can baffle few or it can even break the plastic edge.

First insert this edge 

6. The sensor calibration and alarm settings are quite complicated.

7. To enter into zero and sensor calibration, Keys- Set + Power button, need to be pressed.The manual mentions - The calibration procedure requires usage of carbon monoxide (poisonous gas), so it should be done by professionals.

8. The sensor self-test cannot detect CO sensitivity loss caused by lack of gas diffusion when dust or water droplets cover the pin holes for gas diffusion. This is related to sensor-self test not calibration and any other sensor will have the same problem only.

9. The meter records in resolution of 1 ppm, it may be interesting to see in 0.1 ppm but this will definitely double or triple the price.

10. The meter records in ppm, that is, parts per million; it would be interesting to see parts per billion or parts per trillion or parts per zillion and so on.

Precautions/Safety Warnings

The manual mentions some precautions :

1.  Do not allow the pin holes of the sensor blocked by foreign matter or dust. If the surface of the meter is dirty and it requires cleaning, then clean it with wet soft cloth or sponge.

2. Don't clean the device with water directly, in case of water seeps into the circuit board and damages the device.
3. This CO detector is not suitable to detect carbon monoxide concentration in the environment with frequently or drastically changed temperature and humidity.
4. This CO detector can not be used in those places which require explosion-proof devices,

5. Comparable Products

Following prices are without tax and without shipping (and/or custom charges).  

The currency conversion from INR to USD is taken from the website. The amount mentioned in Euro,€ is obtained after INR currency conversion to Euros, €.

The product Multicomp Pro  MP780892 has price tag of  Indian Rupees INR Rs.6,839.69, British pound sterling GBP of £40.24, Chinese Yuan CNY 692.87, Euros € 74.275696 and US Dollars $ 62.00. There are four competitive and comparable products, whose pricing and pros cons are mentioned below : 

1.  Molex KIT-INS-CO-03 

This  meter has price tag of Indian Rupees INR Rs.23,083.59, British pound sterling GBP of £180.54, Euros € 250.66345  and US Dollars $218.99. The currency conversion from INR to USD seems to be incorrect but this is listed on the website.

This is comparable but not with respect to the pricing.

2.  Molex INS-CO-03

This  meter has price tag of Indian Rupees INR Rs.20,504.42, British pound sterling GBP of £150.32, Euros € 222.68122 and US Dollars $218.99. The currency conversion from INR to USD seems to be incorrect but this is listed on the website.

This again is comparable but not with respect to the pricing.

3.  EXTECH INSTRUMENTS CO260

This  meter has price tag of Indian Rupees INR Rs.70,735.99, British pound sterling GBP of £547.23, Euros € 768.20396 and US Dollars $908.11.

This again is comparable but not with respect to the pricing.

    

4. MOLEX KIT-INS-CO-02

This  meter has price tag of  Indian Rupees INR Rs.26,952.35, British pound sterling GBP of £169.91, Euros €  292.58254 and US Dollars $255.69.

This again is comparable but not with respect to the pricing.

Of all the comparable products, the MultiComp PRO MP780892 is a clear winner as it is economical, affordable and measures ppm upto hazardous level which can cause illness.       

6. Add-On

The CO detector/testing instrument can have following add-ons, which will obviously increase product cost and so the following suggested add-ons will form 2-4 variants 

  1. USB Data Logger
  2. SD card
  3. RS 232 
  4. RS485
  5. GPS
  6. Wi-FI
  7. Android Applet connectivity
  8. Optional AC charger : 110VAC/230 VAC or Universal charger 85 VAC -265 VAC
  9. Data printout or connectivity to printer.
  10. ScreenRecorder
  11. Recorder with small camera to record the object being measured.
  12. Parallel measurement of  02, CO and CO2   
  13. Box to keep otherwise more harder plastic covering

7. Conclusion

The product is affordable, economical as compared to only four other market competitors.

The test meter/CO detector/testing instrument performed more than expectations as the maximum level of rated measurement is 1000 ppm but it easily measured upto 1640 ppm, so it looks the limit is 1640 ppm but whether the shown products measure more than 1640 ppm is not conclusive. 

On all the parameters to be judged on, my ratings are 5 out of 5. The basic price (excluding taxes, shipping etc.) to performance ratio is very good.
I will myself use this meter for some personal future research as mentioned in the article.
During my usage of this test equipment, meter product has revealed few excellent points
  • suddenly jumping of detection from 0 to 1640 in 2-3 seconds
  •  lower ppm takes longer time to come back to zero, as compared to falling of the reading from higher ppm to lower ppm !
  • As mentioned in the the 'Measurement recordings section', - 'one recorded reading' is not applicable universally and hence the measurement recordings must not be taken directly as conclusion. The same object do not give the same reading under different environmental conditions, and the other vendor or product made of different material do not give the same reading as the other. 
The CO readings in materials which are commonly used by consumers, vehicles and even some materials burned as ignorance by people/garbage/scrap dealers or the children do as play, the meter brings into notice the harm it causes to the environment and to people's own health. The CO detector/instrument is thus, a necessary tool in such environmental scenarios. 
Seeing these readings, I may use this test meter/CO detector/testing instrument as carry-on device, when working in such environments.

    Anonymous