IICRC

Definition

The Institute of Inspection Cleaning and Restoration Certification (IICRC) is a nonprofit organization that establishes global standards for the cleaning and restoration industry, including mold remediation. Founded in 1972, the IICRC develops consensus-based standards (like the widely adopted S520 for mold remediation), runs certification programs, and approves schools and instructors that teach toward them. No state requires IICRC certification by name. A few states ask for a mold certification of some kind, and since October 1, 2026, Connecticut registers a home improvement contractor that does mold remediation only if it attests to a mold remediation certification from the IICRC, NORMI or another organization its Department of Consumer Protection approves; our mold remediation license requirements by state survey has each state's rule.

Why It Matters

An IICRC credential shows that a technician trained or was examined under the IICRC's program. It doesn't by itself show that a given job follows the S520 standard, so ask how the work on yours will be done. The IICRC S520 standard covers the main parts of a mold job: inspection and assessment, containment and other engineering controls, HEPA filtration, worker protection chosen from a hazard assessment (§1.1), removal vs. cleaning decisions, and the remediator's post-remediation evaluation and independent verification. IICRC credentials belong to individual technicians: the Applied Microbial Remediation Technician (AMRT) requires a course and an exam, and the Mold Remediation Specialist (MRS) requires at least 12 months of field experience and an exam. An IICRC Certified Firm needs at least one active certified technician, not a certified crew. For homeowners, an IICRC credential is one signal among several, next to licensing, insurance, reviews and references. It doesn't guarantee quality work, and its absence doesn't prove poor work: an experienced professional may hold a different credential, or none.

How It's Used in Mold Work

Professional remediators reference IICRC S520 when planning a job and explaining its scope to homeowners and insurance adjusters. The standard describes the state of an indoor environment in three Conditions (ANSI/IICRC S520-2024, Section B). Condition 1 is normal fungal ecology: the ordinary background of spores and traces found in a clean, dry building. Condition 2 is contamination with spores, fragments and other residue from actual growth in the same space. Condition 3 is actual mold growth, whether it is active, dormant, dead, visible or hidden, and whatever the species. Remediation aims to return the affected area to Condition 1. S520 moved away from sizing the response by the area of visible growth (Foreword); it has the remediator use containment and other engineering controls as the job requires to control airborne particles and cross-contamination (§9.2). Sewage is a separate question: the IICRC's water damage standard, S500, classes it as Category 3, grossly contaminated water (§10.4.1), and S520 refers Category 3 situations to S500 (§2.1.2). IICRC credentials have to be renewed: the WRT and AMRT every year with continuing education, and the MRS every two years. To check one, ask who holds it, then look for the company or technician on the IICRC's Global Locator, which searches by location.