Table 3: Comparisons of internal workers according to exposure to water in free time, to air-condition in cabin and aerosol from CT during instruction meeting.

Exposure to CT water 2-12 hours/week Seronegative 6 Seropositive 11 Total 17
Exposure to water in free time 3/6
50.0%
5/11
45.5%
8/17
47.1%
Exposure to air-condition in operating cabin 6/6
100.0%
10/11
90.9%
16/17
94.0%
Exposure during instruction meeting at the 4th CT 3/6
50.0%
11/11
100.0%
14/17
82.4%