BENEFITS

• Useful for initial site testing, especially if fungal growth is not visible.
• Quick and simple procedure.
• Fast turn around times available.
• Low chance of sample contamination.

DISADVANTAGES

• Fungi cannot be fully speciated with this method.  For example, Aspergillus sp. and Penicillium sp. are normally reported together due to the similarities in spore morphology.
• Spore viability cannot be assessed.

MATERIALS

• Air-O-Cell^TM cassette
• Vacuum pump suitable for operating at 15 liters per minute (lpm)
• Rotameter (for calibration of vacuum pump)
• Flexible tubing

Recommended Sampling Procedure

The cassette is designed to operate at a recommended flow rate of 15 lpm.  Lower flow rates may result in a loss of some spores and the accumulation of others in a non-uniform manner.  Higher flow rates may damage the spores. Therefore, it is important not to run the sampling pumps at lower flow rates for longer times to achieve the recommended air volume.

Calibration of Sampling Flow Rate

A specially designed bubble tube, available from the manufacturer, can be used to set the flow rate for the ½" Air-O-Cell mini pump.  It can not be used with any other style of pump or Mini pump and any other type of sampling pump.

SAMPLING DURATION

The sampling time is dependent on the density of particulate in the environment.  It is important not to overload the sample, otherwise it will be impossible to assess the types of spores, pollen and particulates that are present.  The following table represents typical sample times to attain a sharply defined trace with good dispersion of the spores:

SAMPLING PROCEDURE

Quality Control Suggestions

• An effective interpretation is based on the comparison of indoor and outdoor samples.  An outdoor sample will help demonstrate whether spore amplification is occurring indoors.
• Obtain a control sample from a non-complaint area for comparison.
• Sending a blank cassette for analysis periodically is a good practice.
• Flow rate is critical for accurate results. Remember to calibrate and recalibrate the pump prior to all sampling.  (15 liters/minute)
• Never use cassettes that are damaged or expired.

BENEFITS

• The direct exam is inexpensive, and can be performed quickly.
• A useful test for initial site sampling.
• Direct examination of a surface indicates all mold present in a given area.
• Direct sampling may reveal indoor reservoirs of spores that have not yet become airborne.

MATERIALS

For Tape lift:

• Clear (transparent) Scotch or other brand tape (frosted tape hides the spores)
• New plastic bag to hold specimen(s) (provided in a tape lift kit available from EMSL).

For bulk:

• Sterile container or new plastic bag or Whirl-a Pack (provided at your request by EMSL) to hold and transport specimen.

For swab:

• Sterile culturette/swab with appropriate buffer solution to collect and transport specimen (provided at your request by EMSL).

For all matrices:

• Latex/nitrile gloves (also can be provided at your request).

SAMPLING PROCEDURES

Tapelift:

1.Take a few inches of clear tape.  Avoid touching the sticky side, especially the part touching the mold.

2.Wearing gloves, apply the central inch of tape to the suspect area (choose one that is free of extraneous debris).  Apply light pressure to the non-adhesive side.

3.Pull tape off surface with slow, steady pressure, holding the tape edges only.

4.Apply sticky side of tape to the inside of the plastic bag.

5.Ensure there are no folds or creases in the tape.

6.Close bag

7.Put only one sample in each bag.

Bulk:

1.Wearing latex gloves, take a small piece of the suspect material.

2.Place piece inside clean sterile container or new plastic bag or whirl-a-pack bag.

3.Close bag or cap container.

Swab:

1.Wearing gloves, remove swab from packaging material.

2.Remove plug from media tube.

3.Swab the desired area thoroughly, rolling the swab lightly back and forth over sampling area.

4.Insert the swab in the tube, and firmly close cap. 

For all matrices:

1.Label each sample with appropriate information.

2.Complete an EMSL Chain of Custody (COC), available on the website (www.emsl.com), detailing client name and information, project name or number, sample #, and a description of the area.

DISADVANTAGES

• Areas of fungal growth are often small and scattered, so they may not be picked upon sampling.
• Health problems related to indoor microbial growth are generally caused by the inhalation of substantial numbers of airborne spores, sometimes over a long period of time.  The presence of biological materials on a particular surface, is not a direct indication of what may be in the air.
• Not all the spores seen under the microscope may be viable (alive).  It is advisable to combine direct exam samples with culture methods to get a better picture of what molds are present.
• Tape lifts are not able to be cultured.
• If a direct examination of a swab sample is taken, there is no follow up culture.
• Direct examinations of dirt/soil and dust samples can not be performed. 

QUALITY CONTROL SUGGESTIONS

For tapelift:

• Use clear tape, not frosted.
• Do not fold tape onto itself.
• Stick tape on the inside of the plastic bag only.
• Please do not send tape lift samples on slides or coverslips.  They may arrive broken making the sample difficult to analyze.

For bulks:

• Send a representative sample of the specimen if large.  This prevents over-handling of the specimen and possible contamination.  If analysis of a specific portion of sample is required, please note area(s) or take a tape lift of area.

For swab:

• For semi-quantitative sampling, the area swabbed needs to be entered on the chain of custody.

For all matrices