SIMULATION STUDY ON THE INDOOR SPATIAL DISPERSION DISTANCE, DENSITY AND PARTICLE SIZE OF CELLULOSE NANOFIBER IN THE AEROSOL ABOVE PM10 WITHIN THE WORKER’S BREATHING ZONE

Received 2022-07-26; Accepted 2022-11-17; Published 2022-12-31

Abstract

Inhalation of respirable and inhalable particles has been known to cause occupational lung disease such as pneumoconiosis and asbestosis. The study investigates the dispersion behaviour, density and particle size of aerosols mist bigger than 10 µm (PM10) consist of distilled water (control) or CNF 2 %w/v aqueous suspension by simulating a benchtop personal breathing zone of 60 x 60 x 60 cm. The magnesium oxide (MgO) coated slide was used to determine the dispersion and size of the water droplet. Non-coated glass slide was used to collect CNF from the water droplets for the examination under FESEM to verify the nano-morphology and nano-size. The examination of the MgO coated slides showed the distilled water with or without CNF were capable to disperse up to 30 cm radius horizontally within 5 minutes when the aerosol was vertically discharged upward approx. 30 cm height at the rate of 1 ml/min. The distilled water and CNF aqueous suspension produced aerosol mist that contained water droplet with size above PM10 varying between 11 to 35 µm at the radius distance of 10, 20 and 30 cm. The examination under FESEM found the nanofibrous morphology and nano dimension of approximately 12 nm in both specimens of the plain glass slide and CNF 2 %w/v aqueous suspension. The size of the water droplet with CNF is still categorized as the inhalable particulate matter, thus there is a need to determine whether the CNF could be deposited in the respiratory system and cause damage.