Method: Quantitative culture using appropriate media for bacteria and/or fungi. The concentrations of viable organisms are expressed as colony forming units per cubic meter (CFU/m3) of air.
Collection: Andersen N6 and SAS 180/360 air samplers are available for rent from U.S. Micro-Solutions.
| ORGANISM | AGAR MEDIA |
| Bacteria | Inhibitory mold, Sabouraud dextrose, Malt extract |
| Fungi | Inhibitory mold, Sabouraud dextrose, Malt extract |
| Mycobacteria | Middlebrook |
| Staphylococcus/MRSA | Mannitol salt |
| Legionella | DGVP, CCVC, GPCV |
- Calibrate equipment immediately prior to sampling.
- Use appropriate sampling media (see table above).
- Use aseptic technique throughout the collection process.
- Label the agar plate lid with the sample number.
- Do not use masking tape for the label.
- Agar media should be at room temperature before sampling.
- Do not touch agar surface.
- Sampling durations of 2-10 minutes (56.6-283 total liters) are commonly used.
- Heavily contaminated areas (visible fungal growth) may be sampled for a shorter time, e.g. 3 -5 minutes.
- Areas with low levels of contamination (pharmacy rooms, clean rooms, remediated areas) may be sampled for a longer duration.
- Collect an indoor sample from an unaffected area to serve as a control.
- Collect a representative outdoor sample to provide a reference for determining whether certain fungi are being amplified in the indoor environment.
- Submit a blank unexposed agar plate with each sampling event to serve as a negative control.
- For blank samples, do not list a sample volume.
- Replace lids on all agar plates and seal the perimeters of the plates with electrical tape.
- Do not use Scotch tape or duct tape.
Shipping:
- Clearly label each sample with a Sample Number and complete the Chain of Custody (COC).
- Place sealed plates in a Ziploc bag in a box with sufficient packing material to prevent damage along with the completed COC form.
- Ship samples Monday through Friday for receipt within 24 hours of collection.