The final step is the Post Remediation Verification Inspection (PRVI) also known as a "mold clearance test". The post remediation verification inspection needs to be conducted after the mold remediation is completed and before the reconstruction of any building materials.
The IAQS Licensed Mold Inspectors will inspect the areas of previous water and mold damaged building material to verify that all areas are clean and dust free, that the cleaning procedures have been followed in accordance with the mold remediation protocol.
Sampling is a crucial part of post remediation clearance because most, if not all, bioaerosols are invisible to the naked eye. This can make it very difficult to determine the extent or existence of any remaining mold in the remediation area by relying only on the physical senses of sight and smell.
For the purpose of corroborating the consultant’s opinion of clean the air samples collected within the contained work area must contain no more than “Single Digit” raw counts of mold spores identified by the AIHA accredited laboratory direct microscopic examination. For the purpose of corroborating the consultant’s opinion of clean the surface samples collected within the contained work area must contain no more than “Rare” or “No” mold spores identified by the AIHA accredited laboratory direct microscopic examination. Laboratory results will be conveyed verbally within 2 business days of collection.
To overcome this inability, mold samples will be collected of the air and surfaces inside the contained work area. These samples are then analyzed by direct microscopic examination to determine if the water and mold damaged building material has been successfully collected and removed and that the amount of remaining mold spores will not negatively impact the indoor environment once the build-back is complete that the containment is removed.
The air sampling strategy used on this project is designed to detect both living and non-living airborne microbial spores as well as to identify the presence or absence of an elevated airborne mold condition. Air samples are collected on “Air-O-Cell” cassettes with a high volume-sampling pump calibrated to a flow rate of 15 liters per minute. The Air-O-Cell cassette houses a sticky media that traps fungi particles by impaction on the media. The air samples will be sent to an AIHA accredited laboratory for direct microscopic examination to identify the type of airborne microbial spores and determine the airborne concentration of those spores. The spore identification is to genus level unless otherwise specified. The surface samples will be sent to an AIHA accredited laboratory for direct microscopic examination and the identification and semi-quantitative analysis of fungal spores on the tape lifts.
Post Remediation Final Verification Standard
Remediation is considered complete when the contained work area has no established elevations of airborne particulate matter as measured with a laser particle counter, no elevations of mold spores above that of “Single Digit” raw counts with the mold air samples, the presence of either “Rare” or “No” spores identified on the mold surface samples. No remaining areas of an S520 Condition 2 or Condition 3.
These post remediation clearance goals will ensure that the contained work area will have no negative impact on the surrounding unaffected Condition 1 areas once the containment is removed and the previously affected and unaffected areas reach an indoor equilibrium.
With the remediation complete and the PRVI goals attained the containment can be removed. Once removed the indoor environment will quickly reach equilibrium and a Condition 1 (normal ecology) – may have settled spores, fungal fragments or traces of actual growth whose identity, location and quantity is reflective of a normal fungal ecology for an indoor environment.