Low-cost gas sensors get more and more interest in the field
of air pollution monitoring [2], in complement with conventional
methods such as optical/spectroscopic analysers. Compared to the
reference methods defined in the Air Quality Directive [3], low cost
gas sensor would considerably reduce both installation and main-
tenance costs and allow larger spatial coverage especially in remote
areas. Nevertheless, these devices are known to suffer from weak
metrological characteristics, such as their intrinsic lack of selectiv-
ity, which makes them unreliable [4–6]. Although various methods
have been developed and studied to overcome sensors weaknesses,
the calibration of low-cost gas sensors do still represent a challenge