Sampling Procedures
Two hundred and fifty-four air samples were collected at
various sites on a campus university; these included the
study areas in the library, teaching rooms, offices, bookshops,
and restaurants. All the sites selected for sampling
were served by mechanical ventilation and air-conditioning
(MVAC) Systems. One outdoor sample was taken every
day at the plant room during the measurement period, and
a total of 43 outdoor samples were taken. The samples were
collected using the Burkard Single-Stage Air Sampler
with agar plates. The detectable range for this
sampler is 0–2200 cfu m3
, and the lowest detection limit is
8 cfu m3
. The sampling time for the Burkard Sampler was
7 min because according to the protocol set by the
American Industrial Hygiene Association [13], the sampling
time for an Anderson Bacteria Sampler was 5 min.
Since the flow rate of the Anderson Sampler was
28.3 L min1
, while the flow rate for the Burkard
Sampler was 20 L min1
, the sampling time of the
Burkard Sampler was calculated by the following formula:
Sa