Abstract
Airborne particulate matter is an important factor in the quality of an indoor environment. In this study, a miniaturized particle sensor was developed to detect submicron-sized aerosols based on number counting. This particle number (PN) sensor was designed and fabricated for real-time measurement of total aerosol number concentration and geometric mean diameter. The sensor (hereafter called as PN1 sensor) comprised a particle-classification unit, a particle-charging unit, and a particle-detection unit. After integrating all the three units, the total number concentration and the geometric mean diameter of test aerosol particles were determined and the results were compared with those obtained using commercial instruments. First, the PN1 sensor was compared with a condensation particle counter (CPC) in lab-test. For this, different groups of monodisperse sodium chloride particles between 20 and 700 nm in diameter were used. Then the PN1 sensor was compared with a scanning mobility particle sizer (SMPS) and an aerodynamic particle sizer (APS). For this, the PN1 sensor data were obtained by varying the combination of two corona voltage and test particles (sodium chloride and polystyrene latex) size distribution. In addition to lab-test, field test was carried out with indoor aerosols in different places. The number concentration and geometric mean diameter of indoor aerosols were measured by PN1 sensor and compared with SMPS data. The number concentration was also compared with the results of CPC and Pegasor AQ Indoor (Pegasor, Finland) measurements.
Highlights
Airborne particulate matter is an important factor in the quality of an indoor environment
Asbach et al (2012) compared five different portable nanoparticle monitors, including the NanoTracer, and found that the results provided by the NanoTracer were consistent with condensation particle counter (CPC) for sodium chloride (NaCl) particles having 37.8 nm of geometric mean diameter
When the PN1 sensor was compared with a CPC using monodisperse NaCl particles between 20 and 700 nm in diameter, the maximum differences occurred for 20 and 600 nm particle groups and were 31.2% and 35.0%, respectively
Summary
Airborne particulate matter is an important factor in the quality of an indoor environment. In recent years, increasing public concern regarding air quality in residential and nonresidential buildings has led to the development of efficient indoor aerosol-monitoring techniques. Several studies have reported that indoor aerosol particles are of submicron size because these particles are generated, for example, by cooking, human activities, or cleaning (Abt et al, 2000; Long et al, 2000; Morawska et al, 2003). Exposure to submicron-sized particles has an impact on human health when we inhale and the particles enter the body. Particles that are a few microns in diameter are blocked by hair in the nostrils; submicron-sized particles can reach the lungs and deposit in the alveoli (Mitsakou et al, 2007).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.