Comparative Analysis of Airborne Particulates and Indoor Physical Parameters between Dry and Wet Laboratories at the Faculty of Forestry and Environment, Universiti Putra Malaysia

Abstract

Laboratories are special micro-environments in university buildings in which the levels of pollutants depend on the nature of the experiments and the number of people employed. The aim of this study is to compare the airborne particulate (PM2.5) and the physical parameters in the existing indoor environment of Faculty of Forestry and Environment (FHAS) dry and wet laboratories. PM2.5, air temperature (AT), relative humidity (RH) and air speed (AS) were monitored for nine working hours in selected dry and wet laboratories. Dusttrak aerosol monitor and Kestrel 4500 were used to collect the data for PM2.5 and the physical parameters, respectively. Descriptive analysis was performed to summarize the data characteristics. Meanwhile, independent t-test and Pearson’s correlation were conducted to compare the mean variables for dry and wet laboratories and measure the linear association strength between parameters, respectively. The results showed that airborne particulates and RH recorded were below and within the Department of Occupational Safety & Health (DOSH) acceptable limits which is 150μg/m3 and between 40-70%, respectively. Some of the laboratories have AT in the range of 23-26°C while others were not in the acceptable range where Chemical Laboratory recorded the highest (30 ± 0.5°C), while Xylarium was the lowest (18 ± 2.2°C). As for the AS, majority of the laboratories did not have air movement in the range of 0.15 – 0.50 m/s. Some of them recorded no air flow for the entire monitoring hours. Independent t-test analysis showed there was no significant difference between dry and wet laboratories in terms of the airborne particles, AT and RH, except for AS (p<0.05). The results from Pearson’s correlation found that airborne particles have significant relationship with all physical parameters in wet laboratories, while only RH and AS were found significant in dry laboratories. Therefore, it can be concluded that both laboratories have similar indoor air quality except for AS which highly depends on the ventilation systems and occupants’ activities.

Impact of COVID-19 Restriction Measures on Ambient PM10 Concentrations during Universiti Putra Malaysia Convocation

“…The Pearson correlation coefficient is typically used for jointly normally distributed data. The correlation results can be interpreted into one of the following hypothetical scenarios such as very strong, strong, medium, weak, very weak, and no correlation, where the correlation coefficient size (r) is in the range of 0.91 until 1.00 or -0.91 until -1.00, 0.71 until 0.90 or -0.71 until -0.90, 0.51 until 0.70 or -0.51 until -0.70, 0.31 until 0.50 or -0.31 until -0.50, 0.01 until 0.30 or -0.01 until -0.50 and 0.00, respectively [11]. Percentage of reduction of PM10 concentrations was calculated between normal working days (before outbreak) and convocation days (after outbreak) to identify the significant impact of restriction measures taken by the university management in combating the spread of COVID-19 on the level of this pollutant.…”