Hi Maam/Sir!, I am newby to Arduino 
i just want to ask question for my thesis. Our thesis title is Air Quality monitoring system using arduino. Is there any way to separate air pollutants data that detects by the sensor ?. just like my example below. Thank you for Answering and Thankyou in advance This will be a big help for us.
SO2 CO CO2 smoke
77ppm 55ppm 22ppm 100ppm
Are you writing about a real sensor or an imaginary sensor? If a real sensor, then please identify it!!!1
Paul
I'm sorry for that sir. My question is, is there any code for that on any kind of gas sensors that can be separate all the collected data.
Kimarin0:
Our thesis title is Air Quality monitoring system using arduino.
The first step would be to determine what sensors are you going to use.
Then you can ask if an Arduino can monitor them.
Kimarin0:
I'm sorry for that sir. My question is, is there any code for that on any kind of gas sensors that can be separate all the collected data.
Impossible to say without more detail. But let's suppose you're going to go the conventional route and get some MQ series sensors such as the MQ-7 for measuring CO. When wired appropriately, it gives you an analog voltage that, with calibration, will give you an indication of CO levels although temperature and humidity impact the reading too.
But now you've got a single voltage - there is no way to subdivide that into the different gasses you're looking for.
Worse still, just because the sensor is affected by CO, doesn't mean that other gases don't have an effect. So not only can you not distinguish between gasses using such a sensor, you're not even really sure that you're measuring CO - could be one of several others.
this is the answer that i want to hear. thank you sir !
If there is a gas sensor out there that is highly specific for those gases, then there will be code to read them individually from that sensor.
Now first go find that sensor!
As i have searched, there are gases that can sense multiple air pollutants. but according to the answers for my question. there is no way to separate the data for the different pollutants that has been collected by the sensor. And this is our concern for this Topic. 
The MQ sensors are not exactly specific. There may be more specific ones out there. Or combine a number of sensors as done in the "electronic nose" project (don't have the link at hand - do a Google search).
if i can find not MQ gas sensor, Can it be used for arduino sir ?
Probably. Most sensors can be read by an Arduino.
There's another thread about another CO2 sensor active on this board. Do check it out.
Okay Sir thank you so much!
Hello Ma'am/Sir,
I have a question. If we are using sensor to detect many gases such as MQ135 and etc, then how we will know their percentage level SEPARATELY ??
THANK YOU in Advance
I don’t think you can, it just responds the presence of any of the gases .
They are only a few dollars ! Don’t expect too much
Okay thank you
Okay thank you
See this excellent tutorial on how to use several different gas sensors to make an electronic nose.
Thankyou for all your Help and Comments !
