Model STA 203, shown at left. Above, the particle distribution guide helps determine the time of occurence and duration of a contamination event. Principle of Operation A known volume of air is drawn by vacuum through a slit ori-
fice that accelerates the sampled air and its contaminants.
Located below the slit and in the path of airflow is an exposed
agar plate that rotates on a turntable at a selected rate of speed.
The contaminants, because of their higher mass become
impacted on the agar surface, while the rest of the air mass
flows around the plate and exits the air sampler. After incuba-
tion of the agar plate, colonies can be counted and identified.
A particle distribution grid can also be used to help determine
when a contamination event occurred. Applications Features Slit-To-Agar (STA) air samplers have become a lab standard
for detecting airborne microbial contamination. New
Brunswick Scientific has improved the original designs with
two new models that provide a dynamic sampling range,
more precise control and easier validation. STA 203 and STA
204 Models have been successfully used in a variety of envi-
ronments including pharmaceutical facilities, hospitals, food
and cosmetics labs, and in the detection of terrorist-dispersed
anthrax. New Brunswick STA models utilize microprocessor controls,
variable speed turntable and a thermal
mass flow regulator.
This allows the user to select an extraordinarily broad sam-
pling volume range. For
cleaning room environments, the STA
203 can sample a volume up to 5 cubic meters (5000 liters).
In environments with more viable particles, the STA 203 and
STA 204 can sample as little as 0.03 cubic meters (30 liters).Flow rates and sampling time are easily entered using a mem-brane keypad. Total sampling volume is automatically comput-
ed and continuously displayed on a large, easy to read
Led readout. Sample volume for each run can also be output to a
professional recorder for validation purposes.STA 203 is used with a customer supplied vacuum pumpcapable of at least 2.2 cu.ft. air/min at 15” Hg. STA 204 is sup-
plied with a
vacuum pump manufacturers.
NEW BRUNSWICK SCIENTIFIC
Where Quality and Innovation Have Become Tradition