HOW TO REMOVE MOLD ACCORDING TO THE IICRC S520




At the moment of this writing there is no law or legal regulation on how to remove mold in the Maryland and Baltimore area. This creates many different issues. Issues such as:

1. When is the home or business considered mold “ free”

2. Who is considered a mold removal and mold remediation expert.

3. How do you know if the project was performed correctly.

4. When do you call in a company that offers to remove mold and when do you do it your self.




I’ll try in the next few paragraphs to answer the questions above. Remember that any suggestion or explanation of how to remove mold is superseded by the IIRC S520.

First let’s talk about the IICRC S520 Guide lines on mold remediation and who the IICRC is.

The IICRC is The Institute of Inspection, Cleaning and Restoration Certification. As the IICRC states in their web site “ The Institute of Inspection, Cleaning and Restoration Certification is a non profit standard setting body and certification registry, which was founded in 1972 to establish and monitor education programs and standards for the inspection, cleaning and restoration service industries. The IICRC is controlled by 16 non-profit trade associations in Australia, Canada, England and The United States.”


The IICRC S520 is “Remediators and other parties to the remediation process often request specific guidance regarding action levels that trigger remediation activities or confirm remediation success. Quantifying visible levels of mold growth alone are not feasible as an action level decision criterion, because of the wide range of occupant susceptibility and the imprecise measurement of exposure, along with insufficient science to support conclusions in this area as yet.

Thus, S520 provides a philosophical shift away from setting numerical mold contamination action levels. Instead, it establishes mold contamination definitions, descriptions and conditions (1, 2, 3), and general guidance, which, when properly applied, can assist remediators and others in determining criteria that trigger remediation activities or confirm remediation success.

This standard was written over the course of some four years. A minimum of 18 meetings were held in various parts of the US. There were about 35 professionals on the S520 standard development committee, with an additional 60-70 serving on various subcommittees. The first draft was sent out to some 350 industry professionals during the peer review process. The editing committee got back 827 comments, all of which were cataloged, read, and evaluated, and either incorporated into the document, or we recorded the reason for exclusion. Legal review has been accomplished by four lawyers (including lawyers who represent both plaintiffs and defendants).

Although this is not an ANSI-compliant standard, the procedures used in its development followed basic ANSI standard writing protocols.”



In a nut shell, because there are no federal laws and no laws in the State Of Maryland in regards to remove mold from dwellings, the IICRC S520 guidelines for mold remediation is the most popular guide used in the US.

Many if I dare say most Industrial Hygienist use the IICRC S520 to guide their judgements when deciding when, how and where mold should be removed.


The IICRC S520 is used in US court systems, to assist Judges in making rulings.