Leave the Sampling to the Professionals
If you are following the IICRC S520 Standard and Reference Guide for Professional Mold Remediation, then your remediation project will fall into one of two categories. The first would be that the entire building is contaminated and you need an indoor environmental professional, or IEP. The second is that the building is only partially contaminated and you used an IEP to determine Conditions 1-3.
AssessmentWhen a preliminary determination indicates that mold contamination (as defined in S520) exists or is likely to exist, it is highly recommended that an assessment (as defined in S520) be performed prior to starting remediation. It is highly recommended that an independent IEP with no business affiliation to the remediator be used for this purpose. In circumstances where an entire building or system is fully involved as a result of Condition 3 mold contamination or when the scope of work can be determined without sampling or independent IEP inspection and assessment, engagement of an IEP for assessment may not be necessary.
If your project involved an IEP, the IEP will have probably been hired by another party and will probably return to verify your success. Where an entire building has been contaminated, it would be prudent to have an IEP verify the effectiveness of your remediation. In either case you will want to perform some kind of quality control prior to his or her arrival.
13.Following post-remediation evaluation by the remediator, including application of internal quality control procedures, verification of a return to Condition 1 status may need to be determined by sampling and testing, and, if so, it is highly recommended that an independent IEP conduct or oversee that process.
However, the S520 also highly recommends that you perform a post-remediation evaluation, which is different than a post-remediation evaluation. This process is a quality control step that precedes the IEP activities that verifies your remediation effectiveness.
10.13It is highly recommended that a post-remediation evaluation be conducted by the remediator to confirm that the remediation process has been completed. This evaluation involves application of the internal quality control procedures of the remediator, and a sensory inspection of the containment area, to ensure that malodors, contaminated materials, visible dust and debris have been removed.
As mentioned above, this quality-control process initially utilizes sensory inspection skills. Basically this means that you perform a visual inspection of the remediation area to see if it is free of dust and debris while being conscious of any odors. While not the most glamorous of inspection techniques, a visual inspection is highly effective in making a determination that there is no visible mold and that perceivable dust from the remediation process has been removed. In our experience, when we arrive at a remediation site that still has dust and debris present, post-remediation verification samples tend to indicate that that the environment has not been adequately cleaned.
Another quality-control technique that is not very glamorous is the white glove test. Over the years, new technology has captured the interest of most people. We tend to be attracted to newer, niftier tools and high tech gizmos. Unfortunately, the white glove test has lost respect. Companies we have worked with that are good at detailed cleaning and using the white glove have passed post-remediation verification routinely. Actually, alternating between a white and black glove is most effective. Some soils are white and will not show up well on a white glove.
The EPA publication "Mold in Schools and Commercial Buildings" makes the following statement regarding sampling and sampling devices:
"Sampling for mold should be conducted by professionals with specific experience in designing mold sampling protocols, sampling methods, and interpretation of results. Sample analysis should follow analytical methods recommended by the American Industrial Hygiene Association (AIHA), the American Conference of Governmental Industrial Hygienists (ACGIH), or other professional guidelines (see Resources List). Types of samples include air samples, surface samples, bulk samples (chunks of carpet, insulation, wall board, etc.), and water samples from condensate drain pans or cooling towers.