Although odors do not always constitute a toxicological problem—due to both their nature and their concentrations—the olfactory sensations and the annoyance they cause can lead to real health issues, such as headaches, gastric disorders, insomnia, and stress. This effectively compromises the quality of life for citizens and can potentially trigger legal disputes.
But how is a “bad odor” evaluated and measured? The answer is complex and can be found in a combination of regulations, standards, and technologies.
While dynamic olfactometry provides data representative of a specific point in time, continuous emission monitoring requires more innovative solutions. Electronic noses, or IOMS (Instrumental Odour Monitoring Systems), are devices capable of detecting and monitoring the presence and concentration of odors in real time.
Interest in electronic noses is growing rapidly, primarily due to their ability to constantly monitor air quality. These instruments offer a significant advantage: they eliminate the need for manual sampling and analysis, which are more complex, time-consuming, and expensive.
However, electronic noses also have a significant limitation: unlike the human nose, they lack an intrinsic perception of smells. Consequently, there is a risk of losing the connection with human sensitivity.
The UNI 11761:2023 standard defines the steps necessary for the qualification of an IOMS system. The standard establishes that, once installed, the instrument must be characterized by comparing it with reference measurements obtained through the olfactometric method (UNI EN 13725). It also requires periodic checks to ensure that the correlation between the instrument’s measurements and the detected odors remains valid over time.
In the installation process of our OlfoSense electronic nose, for example, we ensure that this intrinsic limitation is resolved, guaranteeing an effective correlation between the measurements and human odor perception.
Our sampling and analysis service according to UNI EN 13725 plays a fundamental role. Before field installation, sampling of sources and ambient air is conducted on-site. The dynamic olfactometry data, obtained in the laboratory from the samples collected on-site, are used to calibrate the electronic noses by correlating them with the measurements taken by the electronic nose on those same samples. Once calibrated based on values obtained via olfactometry, the noses are ready for installation, guaranteeing results in line with human odor perception.
