Health Effects of Indoor Air Filtration in Healthy Chinese Adults

The 17 dormitory rooms and their residents were randomized into two groups: the intervention and control group. The intervention group went through a 9-day intervention with an air purifier placed in the center of the room. All rooms in this group used the same qualified air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms with the windows/doors closed throughout intervention period. All participants and research staffs were blinded to the group assignment.

The control group went through a 9-day intervention with a sham air purifier (with its filter gauze removed) placed in the center of the room. All rooms used the same air purifiers (model KJEA200e, 3M) as the intervention group, except the filter gauze was removed. During the study period all participants were required to stay in their dormitory rooms with the windows/doors closed. All participants and research staffs were blinded to the group assignment.