TITLE:
Low-Cost Sensors Calibration for Monitoring Air Quality in the Federal District—Brazil
AUTHORS:
Erick Frederico Kill Aguiar, Henrique Llacer Roig, Luís Henrique Mancini, Eduardo Neiva Caetano Botelho de Carvalho
KEYWORDS:
Low-Cost Sensors, Monitoring Air Quality, Calibration of Micro-Sensors MiCS-5521 (CO/VOC), WebGIS
JOURNAL NAME:
Journal of Environmental Protection,
Vol.6 No.2,
February
25,
2015
ABSTRACT: Critical situations that cannot be solved by conventional approaches
(traditional air quality monitoring networks), have the possibility of being
managed quickly by a wide network of portable systems with sensors. The purpose
of this research was to calibrate and validate low-cost sensors. Pilot indoor
and outdoor areas, in the central area of Brasilia (Brazil’s capital city) were
chosen for corporative performance evaluation of the sensors. The CO at 99.999%
volumetric injection method has been used in a gas test box, among two
MiCS-5521 (CO/VOC) sensors, one being new and the other one with a short useful
life. The number of injections adopted to each volume (from 1 ml to 6 ml) was
10, rising each sensor’s confidence interval mean. A increase of the injected volume
(ml) of CO resulted in significant decrease in a resistance (Ohms), as shown by
a good inverse relationship on the interaction of these two variables (r =
0.88), with good measurement accuracy, when compared to the manufacturer’s
reference datasheet. Finally, a geospatial management system was built for the
pollution data measured by the low-cost sensors.