3. ENUMERATION OF
MICROORGANISMS IN AIR
Various methods commonly applied for
enumeration and detection of microorganisms can
be subdivided into:
• Microscopic methods
•Culture methods
•Combination of both
4. MICROSCOPIC METHODS
Letting the air through
filter paper
Placed on a glass slide
using Vaseline
Staining of trapped
microorganism
Fluorescent microscopy –
Acridine orange
Live and Dead can be
differentiated
5. DRAWBACK
• Possible to detect and identify other biological agents e.g. plant pollen,
allergenic mites, abiotic organic dust (fragments of skin, feathers,
plants, etc.).
• Inability to determine the species of microbes (bacteria, fungi,
viruses).
8. Preparation of culture medium
Nutrient Agar
PDA
Exposing to Air
Incubation at Bacteria : 37℃ for
24hrs
Fungi : Room temp
Counting Colonies
Microscopic examination
IMPINGEMENT ON SOLIDS