Abstract
This work describes the methodology adopted to analyse the olfactory properties of different gas odorants, with the aim of evaluating the possibility of introducing a new, sulphur-free gas odorant (Gasodor® S- Free). For this purpose, the compliance with the current regulation on the matter, i.e. the Italian Norm UNI 7133:2012 was verified, which specifies that “the odour given to the gas by means of the odorant shall be characteristic, unpleasant and of constant type at any concentration in air”. Sensorial tests were run comparing the odorant S-Free with the two traditional odorants (TBM/IPM/NPM and THT) and with other “interfering” odours, in order to verify that the odour of the tested odorant is “characteristic”, thereby meaning that it shouldn’t be confused with other odours that might commonly be perceived in a domestic environment, in the case of an accidental gas leak. The Principal Component Analysis (PCA) applied to the results of sensorial tests shows that the odour of the S-Free is recognized as similar to the odour of the other traditional odorants, and that it is clearly discriminated from the interfering odours. These results indicate that the odour of the S-Free odorant is “characteristic”, meaning that it is not confused with other interfering odours. Moreover, this study points out the effectiveness of the proposed methodology for the qualitative evaluation of the olfactory properties of gas odorants.
