Fig. 1
Layout of Sierra Leone-China Friendship Biological Safety Laboratory. The SLE-CHN Biosafety Lab mainly consists of a BSL-3 laboratory with negative pressure, a BSL-2 laboratory, a PCR preparation room, a storage room and two sets of dressing rooms (including two 1st changing rooms, two shower rooms and one 2nd changing room). The BSL-3 lab is connected to other labs through two transfer windows (a “clean” transfer window and a “dirty” transfer window). In addition, it contains a central control room and offices on the left side, and a decontamination room, an electricity distribution room and an air conditioning engine unit on the right side. The lab was divided into four zones, including a green zone, a yellow zone, a brown zone, and a red zone, which are indicated in the corresponding colours. Blue lines show the routes for specimen transportation through the lab