Natural gas, biomethane and LPG (Liquefied Petroleum Gas) circulating in distribution networks or stored in special tanks, are gas mixtures which are odorless. In order to allow leak to be detectable also by people without specific instruments, they add some substances, called Odorants, used to odorize above-mentioned gas and make them detectable to human nose. Essentially, there are two types of odorants: tetrahydrothiophene (THT) or tert-butyl mercaptan (TBM).

At the moment, odorization level verification and monitoring are mainly carried out by the use of portable micro gas chromatographs, installed on specific mobile vehicles, which regularly carry out odorization level analysis on pre-defined network points.

Monitoring odorants level in automated and online way directly on the network in the most strategic points has the operative advantage to detect possible odorants deficiency or possible concentration increase, taking the necessary countermeasures in an automated or semi-automated way (it depends on the automation level required). High level of automation and remote connection potentiality make it possible to interconnect different network operating units to optimize odorants quality used, minimizing its consumption and improving all the THT and/or TBM management, consumption and transport costs.