  Human exposure to Volatile Organic Compounds (VOCs) and their presence in
indoor and working environments is recognized as a serious health risk, causing
impairment of varying severity. Different detecting systems able to monitor
VOCs are available in the market, however they have significant limitations for
both sensitivity and chemical discrimination capability. During the last years
we studied systematically the use of Fourier Transform Infrared Spectroscopy
(FTIR) spectroscopy as an alternative, powerful tool for quantifying VOCs in
air. We calibrated the method for a set of compounds (styrene, acetone, ethanol
and isopropanol) by using both laboratory and portable infrared spectrometers.
The aim was to develop a new, real time and highly sensitive sensor system for
VOCs monitoring. In this paper, we improve the setup performance testing the
feasibility of using a multipass cell with the aim of extending the sensitivity
of this sensor system down to the part per milion (ppb) level. Considering that
multipass cells are now available also for portable instruments, this study
opens the road for the design of new high-resolution devices for environmental
monitoring.
