Investigation on Contamination Situation of Centralized Air Condition Systems in Hotels in Shenzhen City / 环境与健康杂志

Objective To know the contamination situation of the centralized air conditioning-ventilating systems in hotels in Shenzhen City, Guangzhou province and to ensure the indoor air quality when the centralized air conditioning-ventilating systems were at working. Methods 22 hotels were selected to determine the total count of bacteria and fungi in internal surface of pipes and air blow, the dust volume of internal surfaces of pipes, inhalable particulate matter(PM10) in air blow, and Legionellae in cooling tower water. Results The eligibility percent of dust volume, the total number of bacteria and fungi in internal surface was 94.76 %, 95.71% and 91.90 % respectively,the eligibility percent of PM10, the total count of bacteria and fungi in air blow was 42.54%, 94.76% and 84.29% respectively, and the detected rate of Legionellae was 57.50%. Conclusion The pollution in some degrees has been observed in the centralized air conditioning-ventilating systems in hotels of Shenzhen City, so it is considered as the important measure to improve indoor air quality and ensure people health to strengthen management of centralized air conditioning-ventilating systems in the usage.

Change of Formaldehyde Level in Indoor Air in Newly Decorated Houses in Beijing / 环境与健康杂志

Objective To investigate the formaldehyde pollution in the indoor air in some newly decorated houses in Beijing and analyze the dynamic changes in order to find the change law of formaldehyde. Methods 54 residences were randomly chosen in Beijing to monitor the formaldehyde levels. The temperature and humidity were recorded at the same time. Covariance analysis was used to analyze the influence of temperature and humidity on formaldehyde pollution levels. Results In six consecutive months of monitoring after the decoration, the monthly average concentrations of formaldehyde in the indoor air were 0.04 mg/m3, 0.04 mg/m3, 0.13 mg/m3, 0.15 mg/m3, 0.02 mg/m3 and 0.03 mg/m3 respectively. The influence of temperature and humidity on formaldehyde levels was significant. Conclusion The formaldehyde level in the indoor air after decoration is mainly affected by the season and time. Residents should open the windows more often and it is suggested to live in the newly decorated houses in six months as the decoration finished.