Problems related to odors in the passenger compartment have been drawing attention. Products such as healing aroma, arousal and so on have effects such as smell generating equipment attached to the air conditioning equipment even in the car industry was sold. In recent years, many commercial products such as fragrances and deodorants are on the market. In current air conditioning systems for vehicles, most of the vehicles aimed at the deodorizing effect by attaching activated carbon or the like to the filter. However, there are many complaints about the smell in the cabin. As for smell, it is also fact that there are individual differences due to preference issues. Here, we introduce the summary of this standard in response to the issuance of the ISO 12219-7 standard for smell measurement in the passenger compartment in 2017.

In response to the growing health consciousness, interest in the air quality has been increasing in recent years. Volatile organic compounds (VOC) generated in indoor houses have been improved in countermeasures such as building materials and materials, and have been greatly improved as compared with before countermeasures. In automobiles, as well as housing, countermeasures for interior materials and materials used in the passenger compartment are progressing, and the VOC concentration in the passenger compartment is decreasing. However, the interior environment of the passenger compartment is smaller in volume than the residential environment, and the temperature is also high, so it is a severe environment as an air quality environment. Therefore, considering the total volatile organic compounds (TVOC) and “smell” which are indicators of air quality, the air quality in the passenger compartment was considered.

There are odor substances generated from interior materials of motor vehicles, which is unpleasant by some people.

To turn off the odor, it is necessary to identify odor substances. It is effective for identifying the odor substances to use instrumental analysis by sniffing GC/MS (GC-O/MS) and sensory analysis by sense of smell. We could confirm the validity of identified odor substances by comparing the similarity between original odor and simulated odor composed of the odor substances. We established the method to prepare the simulated odor which has high similarity for original odor, by using the method to separate and fractionate the identified odor substances by GC. We can evaluate the effects of each odor substances for original odor by changing the combination of substances of simulated odor.

Summary of the fragrance addition technology for vehicle cabin. With introducing the mechanism of smells in the cabin, HVAC system for control smell, fragrance addition technology and caution points. Controlling the fragrance concentration and diffuse amount are important. To control dilute and interval diffusing, introducing forced sub-flow diffuser as effective device.

The objective of this study was to evaluate olfactory perception in Multiple Chemical Sensitivity (MCS) patients. MCS patients and healthy subjects performed odor threshold test using five odors (β-phenyl ethyl alcohol [A], methyl cyclopentenolone [B], isovaleric acid [C], γ-undecalactone [D], and skatole [E]) of T&T olfactometer, odor identification test using four odors (Japanese orange, Japanese cypress, perfume, and odorless) selected from Odor Stick Identification Test for Japanese (OSIT-J). Psychological evaluation of perceived intensity and pleasantness for each odor used in the threshold and identification tests were also performed. Our results indicated that MCS patients had significantly lower detection threshold for odor D and means of detection and cognition thresholds of five odors, but identification ability was equivalent between MCS patients and healthy subjects. Additionally, perceived intensity and unpleasantness of some odors were significantly higher for MCS patients than for healthy subjects. Because this study was conducted with a small number of volunteers using a limited type of odors, we should increase the reliability of data to investigate the olfactory perception of MCS patients.