The licensing structure most homeowners do not know
Article 32 of the New York State Labor Law licenses mold assessment, mold remediation and mold abatement as separate roles, administered by the New York State Department of Labor. An assessor writes the scope and performs the post-remediation verification. A remediator performs the work. Using one license for the other role is a compliance problem, not a shortcut.
In buildings with 10 or more dwelling units, or on a zoning lot with 25,000 or more square feet of non-residential floor area, Local Law 61 of 2018 adds filing requirements with NYC DEP. The remediator files a work plan no later than two business days before the work starts. The assessor files a post-remediation assessment and certification within seven days of completion.
Why mold is a moisture problem first
Mold needs water, and it does not need much. A slow supply line weep behind a vanity, a failed shower pan, a basement that floods twice a year, or a bathroom exhaust that vents into the attic instead of outside will all support growth. Killing the visible mold without fixing the moisture just schedules the next job.
Remediation therefore has two halves. Remove the growth and the contaminated material under containment, and correct the moisture source so it does not return. The second half is the one that gets skipped, and it is the one that matters at the one year mark.
What remediation actually involves
Containment with negative pressure, HEPA filtration, removal of porous materials that cannot be cleaned, HEPA vacuuming and damp wiping of surfaces that stay, and post-remediation verification by an assessor who did not perform the work. Clearance is a documented result, not an opinion.
We do not treat visible mold with a spray and call it remediation. We do not issue a clearance on work we performed. If the building falls under Local Law 61, the DEP filings are part of the job, not an extra.
Clearance, retesting and what a report should say
Post-remediation verification is performed by an assessor who did not perform the work and holds the assessment license. The report should state the work area, the methods used, the moisture readings that closed the job, and the visual or sampling result. New York does not set a numeric airborne mold limit, so a report that claims a legal threshold is inventing one.
If sampling is used, the usual approach is a comparison of indoor and outdoor samples rather than an absolute number. Sampling is not a substitute for a visual inspection of the work area, and a clearance based only on a lab result with no visual inspection is weak evidence.
Questions we get on this scope
Does my landlord have to fix mold in a Brooklyn apartment?
NYC HPD enforces mold violations, and Local Law 55 of 2018 put indoor mold hazard work practices into the housing maintenance code. If the mold covers 10 square feet or more in a building with 10 or more units, licensed assessor and remediator documentation is required with the Certification of Correction.
Is there a legal limit for mold in a home?
No federal numerical standard exists. The EPA publishes guidance but no exposure limit. What governs the work is state licensing law, the building code, and the S520 remediation standard.
Can I stay in the apartment during remediation?
For a contained small job, often yes if the work area is sealed and negative pressure holds. For a large loss, or any job involving Category 3 contamination, plan to be out for the duration.
Will the mold come back after remediation?
Only if the moisture comes back. Remediation removes the growth and the contaminated material. If the supply line weep, the shower pan leak or the basement seepage is still there, growth returns on the same schedule. The moisture fix is what makes the remediation last.