Air: 6.5
Con: 200-10000

For New Curve (R² >= 0.9995):

for ppm = a*ratio^b:

Gas    | a       | b
LPG    | 6.1067  | -0.4102
CH4    | 6.987   | -0.3777
H2     | 7.4265  | -0.2847
alcohol| 10.8274 | -0.2104
CO     | 8.2236  | -0.1492

for ppm = 10^[(log10(ratio)-b)/m]:

Gas    | m       | b
LPG    | -0.4102 | 0.7858 
CH4    | -0.3777 | 0.8443 
H2     | -0.2847 | 0.8708 
alcohol| -0.2104 | 1.0345 
CO     | -0.1492 | 0.9151 


For Old Curve:

for ppm = a*ratio^b:

Gas    | a       | b
LPG    | 6.1067  | -0.4102
CH4    | 6.987   | -0.3777
H2     | 7.4265  | -0.2847
alcohol| 10.8274 | -0.2104
CO     | 8.2236  | -0.1492

for ppm = 10^[(log10(ratio)-b)/m]:

Gas    | m       | b
LPG    | -0.4102 | 0.7858 
CH4    | -0.3777 | 0.8443 
H2     | -0.2847 | 0.8708 
alcohol| -0.2104 | 1.0345 
CO     | -0.1492 | 0.9151 

LPG
200,0.7
500,0.47
800,0.39
1000,0.36
1500,0.3
2000,0.27
3000,0.23
5000,0.19
10000,0.146

%5.54
[(200,0.7), (500,0.47), (800,0.39), (1000,0.36), (1500,0.3), (2000,0.27), (3000,0.23), (5000,0.19), (10000,0.146)]

CH4
200,0.94
500,0.673
800,0.56
1000,0.515
1500,0.445
2000,0.403
3000,0.34
5000,0.276
10000,0.204

%7.92
[(200,0.94), (500,0.673), (800,0.56), (1000,0.515), (1500,0.445), (2000,0.403), (3000,0.34), (5000,0.276), (10000,0.204)]

H2
200,1.74
500,1.215
800,1.04
1000,0.983
1500,0.87
2000,0.82
3000,0.77
5000,0.73
10000,0.66

%15.12
[(200,1.74), (500,1.215), (800,1.04), (1000,0.983), (1500,0.87), (2000,0.82), (3000,0.77), (5000,0.73), (10000,0.66)]

alcohol
200,3.5
500,2.933
800,2.7
1000,2.56
1500,2.3
2000,2.24
1500,2.35
3000,2.05
5000,1.8
10000,1.45

%39.38
[(200,3.5), (500,2.933), (800,2.7), (1000,2.56), (1500,2.3), (2000,2.24), (3000,2.05), (5000,1.8), (10000,1.45)]

CO
200,3.88
500,3.2
800,3
1000,2.87
1500,2.65
2000,2.56
3000,2.45
5000,2.373
10000,2.27

%44.15
[(200,3.88), (500,3.2), (800,3), (1000,2.87), (1500,2.65), (2000,2.56), (3000,2.45), (5000,2.373), (10000,2.27)]
