Smell Scale

Is there a measurement for smell?

Measuring Farmstead Odors

Not a direct answer to your question but gives you the idea that people are trying to measure these things.

"Methods of Odor Measurement
A scentometer is a simple, hand-held odor dilution device used to measure odor concentration in the field. …

An olfactometer is a laboratory device that distributes sample dilutions to odor panelists. …Olfactometry is used to measure odor concentration, intensity, and offensiveness.

Electronic Nose
Electronic noses mimic the human olfactory system using polymer sensors to simulate receptors in the nose and a computer to simulate the brain. …The main use of an electronic nose is to compare differences between mixtures of odors. The primary drawback is the electronic nose must “learn” a pattern of sensor responses before it can make future comparisons. Work is underway to devise electronics that will allow the nose to “guess” new odors. …

Chemical Methods
Chemical methods are used to determine the actual concentration of individual odorants in a sample taken from the field. The most common instrument used in odorant analysis is a gas chromatograph with a mass spectrometer detector. Like the electronic nose, a gas chromatograph distinguishes compounds by comparing to a reference standard."