Analysis of ventilation effect on children health at child care centres (CCCs) / Abdul Malik Zainal Abidin

Many studies have been conducted to assess the impact of indoor air quality (IAQ) on human’s health. However, there is still a lack of literature available on the adverse health effect of children’s respiratory health at child care centre (CCC). The goal of the study is to establish a holistic guideline to assist air-conditioning and mechanical ventilation (ACMV) designer, operator and maintenance for a better air quality in child care facilities. Modified American Thoracic Society and the Division of Lung Diseases (ATS-DLD-82) questionnaire was used to gather information from parents regarding their children’s respiratory symptoms. IAQ parameters measured were air temperature, humidity, carbon dioxide, carbon monoxide, volatile organic compound (VOC), formaldehyde (HCHO), respirable particles (PM2.5), bacteria and fungi count while information on CCC characteristics and potential surrounding air pollutants were collected via a combination of area monitoring, inspection and interviews. Then followed by the second phase where improvement on ventilation system is proposed at one child care centre. Among 620 respondents, 335 (53.9%) experienced coughing and/or cold and 178 (28.7%) had a productive cough in the last 12 months prior to the interview. Factors found to be significantly associated with respiratory symptoms were child’s age, ventilation system, CCC location, floor area and high bacteria concentration. Children attending CCCs supplied with ACMV had the highest risk for persistent productive cough with adjusted odds ratio (AOR) 5.56 (CI 95%: 2.20; 14.00). With all the assumptions for multiple logistic regression had been fulfilled, predictive factors for persistent productive cough were children with age less than two years, ACMV, interaction between ACMV and temperature, and floor area of less than 3.5m2. High PM2.5 and airborne bacteria concentration may contribute to the factors that trigger respiratory symptom. The result of intervention showed significant reduction for TVOC, HCHO, PM2.5 and bacteria concentration in about 61.9%, 63.6%, 84.5% and 30.4% respectively. Cough and/or cold experience among children reduced about 3.1%. The results also indicated positive correlation between bacteria concentration and moisture content in indoor air with observed correlation coefficient (r) of 0.466. This study has provided recommended guideline on ventilation and IAQ at CCC served by ACMV. Apart from that, the study provides baseline data on indoor air quality and root cause that may be influencing indoor air contaminants, which in turn aid policy makers in formulating good guidelines on ventilation and indoor air quality at CCC in Malaysia.