Is There Mold in Your Carlsbad Home (Part 4 of 5)?

If you missed the first 3 articles in this series you can read them below:

Is there Mold in Your Carlsbad Home (Part 1 of 5)

Is The Mold in Your Carlsbad Home (Part 2 of 5)

Is There Mold in Your Carlsbad Home (Part 3 or 5)

This series has been written by Andy Konopacki, Founder and President of Vm3 Environmental in Carlsbad, who I know personally and who graciously agreed to be a guest contributor on this blog.

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In my last post, I wrote in detail about the ins and outs of performing a mold inspection. Within that post, I briefly mentioned sampling as a means to identify conditions that may further warrant evaluation and ultimately the determination of whether or not to perform mold remediation. 

Upon completion of the visual survey / inspection, a mold inspector will sit down with his/her client and discuss the findings of the visual inspection. Suspect areas that have been documented are then recommended for sampling. The purpose of collecting samples is to determine whether a suspected stain, blemish, discoloration or other water damaged area is identified, by laboratory analysis, as mold growth.

There are two primary methods of sampling used by an inspector; surface and air sampling. Samples are recommended based on observations made during the visual inspection. 

• When the inspector observes visible mold, he/she will recommend surface sampling, interior air sampling and exterior air sampling for that area. For structures less than 5000 square feet, only one air sample is required outside regardless of the number of indoor samples recommended.
• When no visible mold is observed but suspect conditions are present, the inspector will recommend only air sampling.

SURFACE SAMPLING

Surface samples are collected using either clear adhesive tape or wetted swabs. Surface samples collected via adhesive tape are simple to collect and they do not require any expensive equipment. This type of sample can provide qualitative and quantitative analyses (how much and what type) of the mold present on the surface.

The disadvantage of using adhesive tape is the small surface area used for collection and the inability to be cultured in a laboratory. Using wetted swabs is similar to collection via adhesive tape. There are however some distinct differences. In addition to providing qualitative and quantitative results, swabs can sample a much larger area and can also be analyzed by both direct microscopy and cultured for viable sample analysis.

The disadvantage of using a wetted swab is the potential for damage to the mold structure while sampling making the identification of the mold more difficult. And both types of sampling do not identify mold present in the ambient air.

AIR SAMPLING

Air samples are collected using a vacuum pump drawing in air at 15-20 liters per minute. Air cassettes, known as cassette slide impactors, are used with the vacuum pump to capture mold spores in the ambient air. This method of collection is commonly referred as inertial impaction.

The advantages of this method of sampling are expedited qualitative and qualitative analysis (how much and what type) of mold present and no special handling or packaging for cassette. 

The disadvantage of air sampling is that mold collected on the slide within the cassette cannot be cultured. And air cassettes can also be sensitive to particulate overloading.

NOTE: As you can see, each method of sampling has its advantages and disadvantages. While a visual inspection will point out suspect conditions, sampling can be an extremely beneficial addition to determining the existence of mold, whether visible or hidden.

 Andy Konopacki
President - VM3 Environmental, Inc.
760-273-9728(San Diego County - Carlsbad)
949-269-3073(Orange County)

310-295-1099(Los Angeles County)

TOLL FREE: 866-513-MOLD