Environmental Division

Odor measuring

We are officially certified to perform odor measurements by employing olfaction method. According to the Offensive Odor Control Law in Japan, companies are required to prevent 22 kinds of specified odors, utilizing density or olfaction measuring.

About olfaction odor measurement method

The olfaction odor measurement method is a method of odor evaluation with the human sense of smell as the assessment tool. I.e. a specialist’s olfaction is used in every step of the odor suppression procedure, by evaluating the odor intensity based on the samples.

About Odor index

Odor index indicates the intensity of odor based on the technique of dilution of air until the odor is completely intangible by human olfaction. The common logarithms of measured density is tenfold.
Odor index = 10 x common logarithms.
*I.e. if it is necessary to dilute the odor hundredfold to turn it intangible, the odor concentration would be 100 – Odor index 20.

Three bag odor comparison method

Three bag odor comparison method is a odor measurement technique. It is based on determination of which one of three presented bags contains the odor substance (two other are filled with odorless air). The test is conducted by six individuals certified in olfaction odor measuring. The bag containing odor substance is diluted until all of the six testers are unable to sense it in neither of three bags, and based on the results the dilution rate and the odor index are calculated.

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