IICRC Standards Explained: What S500, S520 and S700 Require

IICRC standards are voluntary, ANSI-accredited consensus documents that set procedures for restoration and cleaning work: S500 for water damage, S520 for mold, S700 for fire and smoke, and S100 for carpet cleaning. They are not laws. Contracts, scopes of work and insurance adjusters do use them as the yardstick for professional work, though, which is why it pays to know what they ask for.

Advanced DRI is an IICRC Certified Firm, and our technicians train to S500 and S520 through IICRC courses such as WRT, ASD and AMRT. This page covers which standards exist and their current editions, whether they carry legal weight, what S500 means by "dry", and the drying records you should expect to see on your own job.

What Is the IICRC?

IICRC stands for the Institute of Inspection, Cleaning and Restoration Certification. It is a non-profit that does two separate jobs, and people often blur them together.

• It certifies people and companies. Technicians earn credentials such as WRT (Water Damage Restoration Technician), ASD (Applied Structural Drying) and AMRT (Applied Microbial Remediation Technician) through training and exams. Companies that meet the IICRC's requirements can become Certified Firms.
• It writes standards. The IICRC is an ANSI-accredited standards developing organization, so its main documents carry the "ANSI/IICRC" prefix and are published as American National Standards.

The organization dates to 1972, when Ed York founded it as the International Institute of Carpet and Upholstery Cleaning, according to the IICRC's own history page. Carpet cleaning came first; the water damage standard followed much later, in 1994, per magicplan's S500 history.

The Current IICRC Standards (and Which One Applies to Your Job)

Each standard covers one type of work. The table lists the ones a property owner is most likely to run into, with the most recent edition we could confirm as of October 2026.

Standard	What it covers	Current edition
ANSI/IICRC S500	Professional water damage restoration	2021 (5th edition)
ANSI/IICRC S520	Professional mold remediation	2024 (4th edition)
ANSI/IICRC S700	Fire and smoke damage restoration	2025 (first edition)
ANSI/IICRC S540	Trauma and crime scene cleanup	2023 (2nd edition)
ANSI/IICRC S590	Assessing HVAC systems after water, fire or mold damage	2023 (first edition)
ANSI/IICRC S100	Cleaning of textile floor coverings (carpet, rugs)	2021
ANSI/IICRC S800	Inspection of textile floor coverings	2023

Editions per R&R (S500, 2021), R&R (S520, 2024), R&R (S700, 2025), R&R (S540, 2023), ISSA (S590, 2023) and the ANSI blog (S100, S800). Standards get revised, so check the IICRC store for the edition in force on your project date.

Which one applies is usually obvious from the loss: S500 on any water intrusion, S520 once mold growth is present, S700 after a fire, S540 after a death or crime scene, and S590 when the HVAC system needs a documented assessment after a water, fire or mold event. A burst pipe that sat for two weeks behind a wall can bring both S500 and S520 into the same job.

Standard vs. reference guide

The water and mold standards come with companion reference guides (R500 for water, R520 for mold). The standard is the procedure: what to do. The reference guide explains the science and reasoning behind it, and it is explanatory rather than procedural. When someone says "the IICRC guidelines," they usually mean the standard and its reference guide together.

Are IICRC Standards Law? And the Laws That Sit Above Them

No. IICRC standards are voluntary consensus standards, not statutes or regulations. No state agency enforces S500 the way it enforces a building code.

They still carry weight in three ways:

• Contracts. When a contract, scope of work or project specification says the work will follow S500 or S520, the standard becomes part of what was promised.
• Insurance. In our experience, homeowner policies rarely name S500. Adjusters and independent reviewers do use it as the yardstick when a drying invoice or a mold scope is questioned.
• The standard's own wording. S500 uses defined terms with different weights. As Cleanfax explains, quoting the definitions in the 2015 (4th) edition, "shall" marks a practice that is mandatory because of regulatory requirements or natural law (the physics of drying leaves no alternative), "should" marks the accepted standard of care, "recommended" means advised but not part of the standard of care, and "may" simply means permitted.

So a restorer who skips a "should" item is not breaking a law, but is stepping outside the accepted standard of care and should be able to explain why.

Laws that sit above the standards (NY focus, as of October 2026)

When a law and a standard overlap, the law wins. A few that come up on water and mold jobs in our service area:

• New York State mold licensing. Labor Law Article 32 requires licensed contractors for mold assessment and remediation projects on areas greater than ten square feet (§930). §936 bars one licensee from performing both the assessment and the remediation on the same property, and §947 requires a post-remediation assessment by a licensed assessor for the project to reach clearance. Some owners working on their own buildings are exempt; check §933.
• New York City, Local Law 61 of 2018. In buildings with ten or more dwelling units, or on a zoning lot with 25,000 square feet or more of non-residential floor area, mold projects over ten square feet must be done by Article 32 licensees, and the owner, managing agent and their employees may not do the work themselves. Except in limited cases, the remediator files notice with the city at least two business days before starting (Local Law 61 text; NYC DEP).
• Asbestos in New York. Under Industrial Code Rule 56 (12 NYCRR Part 56), the owner must get an asbestos survey by a NYS-certified asbestos inspector before demolition, renovation, remodeling or repair work, according to the NYS Department of Labor. Flood cuts and flooring removal disturb building materials, so on older buildings the survey question usually comes up before demolition starts; check the rule's requirements with the DOL or a certified inspector.
• Lead paint (all four states). The EPA's Renovation, Repair and Painting rule covers pre-1978 housing. Under 40 CFR 745.82, emergency renovations such as an active water loss are exempt from containment, signage and some other requirements only to the extent the emergency demands; cleaning and cleaning verification still apply.
• New Jersey, Pennsylvania and Connecticut. Mold rules differ from New York's, and local requirements change. Check current state and municipal rules before a project.

This is a summary, not legal advice. Your lease, condo rules, contract or policy can add obligations of their own.

Managing a multifamily building in NYC or a commercial property? See how we handle documented drying and mold work for property managers and commercial owners.

The IICRC Drying Standard: What S500 Means by "Dry"

Under ANSI/IICRC S500, the dry standard is a reasonable approximation of a material's moisture level before the water intrusion, usually found by reading the same material in an unaffected part of the building. The restorer sets a drying goal for each material, reads fixed points daily with the same meter, and pulls equipment when the goal is met.

Two terms carry the whole idea. As R&R summarizes the S500 definitions:

• Dry standard: a reasonable approximation of the moisture content or level of a material before the loss.
• Drying goal: the target moisture level the restorer sets for that material at the end of drying.

Readings from unaffected material are the method, not the definition. Before equipment goes in, the technician reads drywall, framing or subfloor in a room the water never reached, using the same meter on the same scale. That number becomes the baseline. Every wet area is then compared against it, at the same marked points, every day.

Equilibrium moisture content (EMC)

Wood and other porous materials settle at a moisture level that matches the air around them. R&R cites the S500 chart value: most softwood framing settles at about 9.2% (wood moisture equivalent) at 70°F and 50% relative humidity. A house in a humid August reads differently from the same house in January, so a dry stud in an unaffected bedroom beats any generic number.

The photo above, from a 2026 job in Sparta, NJ, shows a pinless (non-invasive) meter scanning the stripped subfloor at the wall base. That spot is exactly where water hides: drywall can feel dry while the bottom plate behind it is still wet, and a carpet can be dry on top with the pad soaked. Readings, not appearance, decide when a floor is dry, which is why a technician may hold equipment on a job the owner thinks is finished. A pinless meter like this one reads without piercing the surface, so it is the quick way to sweep a floor and find the wet edges. Per R&R, that is its job; pin meters, which push into the material, give the repeatable numbers that go into the drying record. More on the difference in how moisture meters read wet materials.

Equipment under S500: placed by readings

Air movers, dehumidifiers and extraction units are tools, not a recipe. A restorer starts with an initial plan based on the size of the wet area and the materials involved, then adds, moves or removes equipment as the daily readings come in. You will still find air-mover ratios online; most come from older editions and are not a substitute for reading the job. For how the machines work, see dehumidification in water damage restoration and how dehumidifiers remove moisture.

Restorers also track grains per pound (GPP) outside, in an unaffected room, in the wet area and at the dehumidifier exhaust. Those numbers show whether the air is actually pulling moisture out of the structure. The math behind it is covered in how GPP and psychrometrics guide drying, the science of structural drying and advanced psychrometrics.

IICRC S500 Documentation Requirements: What a Drying Job File Should Contain

A drying job file that follows S500 typically includes the water source, the Category and Class of water, a moisture map with fixed monitoring points, reference readings on unaffected materials, daily temperature, RH and GPP readings, daily material readings, an equipment log, what was removed and why, and final readings showing each material met its drying goal, with photos throughout.

S500 treats moisture monitoring and record keeping as part of the standard of care. In practice, a complete file looks like this:

1. Initial inspection: where the water came from, when it was found, and safety hazards such as live electrical, plus the building's age for possible lead or asbestos.
2. Category and Class of water, with the reasoning.
3. Moisture map: a floor-plan sketch showing the wet boundary and numbered fixed monitoring points.
4. Reference readings from unaffected material and the drying goal for each material.
5. Daily atmospheric readings: outside, an unaffected room, the affected area and the dehumidifier exhaust (temperature, relative humidity, GPP).
6. Daily material readings at the same points, with the same meter.
7. Equipment log: what was placed, where, and when it was added, moved or removed (industry practice).
8. Removal decisions: what was cut out or pulled (flood cuts, carpet pad, vinyl plank) and why, with photos.
9. Antimicrobial use, if any: which product and where it went.
10. Completion: final readings at or within the drying goal, with the date.
11. Photos from first visit to last (industry practice).

The moisture map does not need to be fancy. A typical one is a simple room sketch: the wet area outlined, points numbered 1, 2, 3 along the wall bases and across the floor, a reference point marked "R" in a dry room down the hall, and small symbols where each air mover and dehumidifier sits. Each day's readings attach to those numbers.

Example layout: daily drying log

This is the shape of a daily log. The cells are blank on purpose; your restorer's software or paper form will look different, but it should hold the same information.

Date	Air readings (GPP): outside / wet area / dehu exhaust	Material readings at fixed points	Equipment changes
Day 1
Day 2
Day 3
Final

How to read your drying log

You do not need to be a technician to tell whether drying is working. Look for four things:

• GPP in the affected area falling toward, then below, the GPP in the unaffected room.
• Dehumidifier exhaust GPP clearly lower than the air going in.
• Material readings at each numbered point trending toward the reference reading.
• Equipment coming out only after the readings meet the goal, not because a set number of days has passed.

Records to ask your restorer for

• The moisture map
• The daily moisture log
• The equipment log
• Final readings for each material
• The photo report

These five documents go a long way when someone later asks whether drying was reasonable. If you are filing a claim, they matter as much as the invoice; our guide to burst-pipe insurance claims covers what else adjusters look for.

Dealing with a water loss right now and no one is taking readings? Our crews map, monitor and document drying to S500 as part of water damage restoration. Call (845) 294-8919, 24/7. Typical arrival is within 90 minutes in nearby service areas.

Categories and Classes of Water Under S500

S500 sorts every water loss two ways. Category describes how contaminated the water is. Class describes how much water there is to evaporate and how hard it will be to get out. They answer different questions, and a good file records both.

Categories: how dirty the water is

• Category 1: water from a sanitary source that poses no substantial risk at the outset, such as a broken supply line.
• Category 2: water with significant contamination that could cause illness if touched or swallowed, such as a washing machine or dishwasher overflow.
• Category 3: grossly unsanitary water that can carry pathogens or other harmful agents, such as sewage, rising floodwater from rivers or streams, and ground surface water flowing into the building.

Water can deteriorate to a higher category with time, warmth and contact with contaminants in the building. Clean water that sits for days under carpet does not stay clean. Once contamination is present, the loss is handled at the higher category. For the safety side of the worst losses, see Category 3 (black water) protocols and our sewage cleanup service.

Classes: how much water and how hard to dry

The class descriptions below are plain-language summaries. The standard's own wording governs.

Class	What's wet	Typical example
Class 1	A small area, mostly materials that absorb little water	A supply line leak caught quickly on a tile floor
Class 2	A larger area, with carpet, pad and the lower part of walls wet	A supply line that leaks overnight and wets the carpet, pad and bottom of the walls in a family room
Class 3	The greatest share of the room, often including ceilings, walls, insulation and floors	A failed pipe on the floor above that rains down through the ceiling
Class 4	Deeply held water in dense, slow-drying materials	Hardwood, plaster, masonry or concrete that stayed wet

Class 4 is the one that stretches timelines. Dense materials release water slowly, so drying them takes different equipment and more patience, and the readings tell you when it is done.

How S520 Fits In When Water Turns Into Mold

When a water loss is caught late, mold becomes part of the job, and mold remediation follows a different standard: ANSI/IICRC S520 (4th edition, 2024). It covers mold work in residential, commercial and institutional buildings, including their systems and contents, and its contents include sections on the indoor environmental professional (IEP) and on post-remediation verification, per R&R's announcement.

The core idea in S520 is source removal. Mold is physically removed from materials that can be cleaned, and materials that cannot be cleaned are taken out, with containment so spores do not spread to clean parts of the building. Spraying a product and walking away is not remediation.

Timing is the link back to S500. The EPA advises drying water-damaged areas and items within 24–48 hours to prevent mold growth. Fast, documented drying is what keeps a water job from becoming a mold job.

Two limits are worth knowing. First, S520 does not cover Histoplasma capsulatum, Cryptococcus neoformans, hantavirus or other highly infectious agents from sources such as bird and bat droppings; the ANSI blog points users to the CDC and NIOSH for those. Second, in New York, Article 32 sits on top of S520 for projects over ten square feet, including the separate licensed assessor described in the law section above.

For the job itself, see our step-by-step mold remediation process and the homeowner's guide to mold remediation.

Fire and Smoke: The S700 Standard

In January 2025 the IICRC published ANSI/IICRC S700, a new American National Standard for professional fire and smoke damage restoration that R&R reports was more than a decade in the making. It covers assessing fire residues and odors in buildings, HVAC systems and contents, restoration cleaning, odor management, contractor qualifications, administrative requirements and documentation, and the Restoration Work Plan. Its scope is fires in or near buildings other than wildfires, so wildfire-impacted structures fall outside it.

For owners, the practical change is the same as with S500: expect an assessment, a written plan and documentation, not just a crew that shows up with sponges. Our fire and smoke damage restoration page and the guide to smoke and soot removal go into the work itself.

What to Ask a Restoration Company

These questions sort a crew that works to the standards from one that only mentions them. Each comes with what a good answer sounds like.

1. Which IICRC certifications do the technicians on my job hold? A good answer names them: WRT for water, ASD for drying, AMRT for mold.
2. What Category and Class did you assign, and why? They should explain it in a sentence, from the source of the water and what got wet.
3. Where are your reference readings, and what is the drying goal for each material? They should point to a specific unaffected spot and give you a number.
4. Can I get the daily moisture log and the equipment log? The answer should be yes, without hesitation.
5. How will you verify the job is dry before pulling equipment? Listen for "final readings at the monitoring points," not "it's been three days."
6. If you find mold, will you follow S520, and in New York, how does Article 32 apply? They should explain who assesses and who remediates (see the law section above).

You can confirm a technician's or firm's certification through the lookup on the IICRC website. For what each credential involves, see what each restoration certification means.

Our IICRC certifications are listed on our certifications page. The IICRC standards are only useful if the paperwork shows they were followed, so ask for the file.

Frequently Asked Questions

What is the IICRC standard for mold remediation?

It is ANSI/IICRC S520, the Standard for Professional Mold Remediation, currently in its 4th edition (2024). It focuses on containment and physical removal of mold, and it leaves certain highly infectious agents to CDC and NIOSH guidance.

More in the S520 section above and on our mold remediation page.

Are IICRC standards required by law?

No. They are voluntary consensus standards that become binding when a contract or project specification adopts them. Laws such as New York's Labor Law Article 32, NYC Local Law 61, the EPA lead rule and OSHA rules still apply on top of them; the law section above has the details.

Where can I get a copy of S500 or S520, and are free PDFs legitimate?

Current editions are sold through the IICRC Webstore, which Gilmore Global runs and which also offers subscriptions, and through the ANSI Webstore. Free PDFs that circulate online are often outdated editions or unauthorized copies, so check the edition year before relying on one.

IICRC Webstore

How often are IICRC standards updated?

They are revised periodically through the ANSI consensus process. Recent editions include S500 in 2021, S540 in 2023, S520 in 2024 and the first S700 in 2025. Before quoting a standard on a project, check the IICRC store for the edition currently in force.

Does my insurance policy require IICRC S500?

Policies rarely name it. In our experience, adjusters and independent reviewers commonly use S500 as the yardstick for whether drying was reasonable and properly documented. That is why the moisture map, daily logs and final readings described above can matter as much as the invoice when a claim is reviewed.

What is the difference between an IICRC standard and an IICRC certification?

A standard is a published procedure, such as S500 or S520. A certification is a credential a technician or company earns through IICRC training and exams, such as WRT, ASD or AMRT. IICRC credentials must be renewed with continuing education.

See what each restoration certification means.

Does S500 set air mover or dehumidifier ratios?

S500 gives a starting point for initial equipment placement, and the restorer then adjusts it from daily readings until each material reaches its drying goal. Fixed ratios that circulate online mostly come from older editions. The readings, not a formula, decide when equipment is added or removed.

More in dehumidification in water damage restoration.

Sources

• ANSI Blog: IICRC Standards: Cleaning, Restoration, Inspection
• IICRC: What is the IICRC?
• IICRC Webstore (Gilmore Global)
• R&R: Revised ANSI/IICRC S500 published (2021)
• R&R: New ANSI/IICRC S520 published (2024)
• R&R: ANSI/IICRC S700 published (2025)
• R&R: ANSI/IICRC S540 2nd edition (2023)
• ISSA: IICRC publishes S590 HVAC assessment standard
• R&R: What is acceptable dry? (2021)
• Cleanfax: Words of wisdom on the S500
• magicplan: IICRC S500 history
• EPA: A Brief Guide to Mold, Moisture and Your Home
• 40 CFR 745.82 (EPA RRP applicability and emergency renovations)
• New York Labor Law Article 32
• NYC Local Law 61 of 2018
• NYC DEP: Mold Abatement
• NYS DOL: Asbestos survey requirements