Restore the microbial composition to that normally found in ambient outdoor and non-affected indoor areas
Factors to Consider When Planning Mold Abatement
It’s important to note that indoor mold problems are associated with moisture intrusion problems. Moisture intrusion problems (such a leaking pipe or roof, improper vapor barrier) need to be addressed as soon as possible. Determining whether the water problems are chronic, or a one-time occurrence helps inform how the remediation project will be designed and executed.
Note that other types of environmental abatement work (i.e., lead and asbestos abatement) often include water sprays and/or misting for dust control. However, on mold abatement projects, an important goal is to dry out the environment to prevent mold from propagating. Professional judgment must be used based upon training and experience when deciding upon the best method(s) for dust control on a mold abatement job, but consideration should be given to HEPA (high efficiency particulate air) vacuuming in place of, or in conjunction with the judicious use of light misting to suppress dust in the work area. Refer to the most recent edition of IICRC S5205 for further information. CT DPH recommends that mold abatement contractors utilize the IICRC S520 method to develop the scope of their remediation project. It may be advantageous to utilize the “size of contamination” approach as ascribed to in the NYC and EPA guidelines to determine the initial type of containment to be used (i.e., source containment, local [mini], or full scale containment). The containment used may be expanded if additional contamination or hidden mold is found.
CT DPH refers to technical procedures and practices covered in IICRC S520 and highlight several specifics in S520 that deserve special attention:
When performing mold remediation from structural members, the contaminated area needs to be isolated from non-contaminant areas to prevent cross-contamination. This typically involves building a barrier or containment structure, usually made with polyethylene sheeting. The integrity of the containment should be checked to ensure that it does not leak, is strong enough to withstand the number of negative air machines that will be used inside, and if pressure differentials are lost, containment flaps will close so that contaminated materials remain inside of the structure. An experienced contractor will know the proper sizing and construction of containment, but be prepared to expand the containment structure if additional mold is discovered (i.e., hidden mold), and the scope of the project is expanded.
If abrasive tools are to be used, the abatement contractor should establish HEPA filtered negative air in the workspace. This limits the potential spread of contamination
“Physically removing mold contamination is the primary means of remediation” It is not acceptable to simply spray a product over mold to cover it up. Indiscriminant use of antimicrobial products, coatings, sealants, and cleaning chemicals should be avoided. They may be used as complimentary tools on certain surfaces after the mold has been removed.
Mold resistant coatings/sealants should not be sprayed on top of actively growing mold.
Fungicidal coatings (those rated to kill mold) should not be used as sealants or encapsulants on active, viable mold.
The use of antimicrobial agents in the form of fogging agents is not recommended for mold remediation in buildings. These are gas or vapor phase antimicrobials that, by the nature of the delivery system, do not offer enough concentration and contact time to be effective at killing mold. Other problems include toxicity, inefficient capture rate, and the fact that physical removal is still necessary after fogging.
Biocides are useful in treating indoor environments flooded with raw sewage.