Hi seemi khan,
Gas sensors are different types, each gas can be detected by different sensors for examle MQ-x, x can be any number according to the gas sensing type
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Semiconductor sensor for Flammable gas, Plastic or Metal cover |
|
|
Model |
Target Gas |
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MQ-2 |
General combustible gas |
|
MQ-3 |
Alcohol |
|
MQ-4 |
Natural gas, Methane |
|
MQ-5 |
LPG, Natural gas, Coal gas |
|
MQ-6 |
LPG, Propane |
|
MQ-7 |
Carbon Monoxide (CO) |
|
MQ-8 |
Hydrogen |
|
MQ-9 |
CO and Combustible gas |
|
MQ216 |
Natural gasCoal gas |
|
MQ306A |
LPG, Propane |
|
MQ309A |
Carbon Monoxide (CO), Flammable Gas |
|
MQ303A |
Alcohol |
|
MQ131 |
Ozone O3 |
|
MQ135 |
Air Quality Control (NH3,Benzene,Alcohol,smoke) |
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Semiconductor sensor for Toxic gas |
|
|
MQ136 |
Sulfureted Hydrogen (H2S) |
|
MQ137 |
Ammonia (NH3) |
|
MQ138 |
VOC (Mellow, Benzene, Aldehyde, Ketone, Ester ) |
refer this link for basic programming for gas sensor
http://www.engineersgarage.com/contribution/microcontroller-based-lpg-gas-detector-using-gsm-module
And for Data acquition search thingspeak navigate to the website there you can get many tutorials regarding storing sensor data to database. there is also matlab based analysis available.