Reference library
Mold & Indoor Air Quality Library
Everything we use to answer mold questions, in one place: plain-English summaries first, the official text behind them, and what Texas law actually requires. Search above, or start with a category.
- Texas law What a Texas statute or TDLR rule requires
- Best practice Guidance from EPA, CDC, OSHA or IICRC — recommended, not required
- Historical Superseded rules, for context
Browse by category
- Mold Basics & HealthWhat mold is, why it grows indoors, and what the science says about its effect on health.9 topics · 10 Q&A
- Water Damage & PreventionMold control is moisture control. Drying fast, finding hidden water, and keeping humidity down.15 topics · 4 Q&A
- Assessment & TestingHow a mold problem is investigated, when sampling helps, and when it doesn't.10 topics · 5 Q&A
- RemediationHow mold is removed safely: containment, protective equipment, cleanup methods and biocides.32 topics · 5 Q&A
- HVACAir conditioning systems, ducts and drain pans — where mold spreads fastest and how it is handled.6 topics · 1 Q&A
- Clearance & CertificatesHow a job is judged finished, and the Texas certificate that proves it.5 topics · 2 Q&A
- Texas Law & LicensingWhat Texas requires: who needs a license, who is exempt, how the work must be done, and the paperwork.18 topics · 2 Q&A
- Buying, Renting & InsuranceMold when you buy, sell or rent a home, and what to know before an insurance claim.4 topics · 5 Q&A
- Common QuestionsStraight answers to the questions people ask most about mold, each backed by the exact words of EPA, CDC, Texas law and the industry standards, with links to the sources.
- In the NewsCourt cases, rule changes and research about mold and indoor air quality, with what each one means for Texas homeowners.1 story
- GlossaryPlain-English definitions of the terms used in mold reports, protocols and the Texas rules.130 terms
- SourcesEvery document behind this library, what kind of authority it carries, and how to browse it.20 sources
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Common questions
Start here
- What mold is and why it grows indoors Mold is a fungus. Its spores are in every breath of outdoor and indoor air, and that is normal. A spore only becomes a problem when it lands somewhere wet and has... Best practice
- Can I clean it up myself? Small, surface mold on hard materials — under about 10 square feet, from clean water, with no one in the home who has asthma or a weak immune system — is usually a... Best practice
- Mold testing: when sampling helps and when it doesn't If you can see mold, you usually don't need a test to know you have a problem — you need to fix the water and remove the growth, whatever the species. Testing earns... Best practice
- The 25-square-foot rule and other exemptions Texas draws one line that drives almost everything: 25 contiguous square feet of mold — the contiguous area of surface material that must be cleaned or removed. Below... Texas law
- Assessor and remediator must be independent Texas doesn't allow one license holder to both assess and remediate the same project, and no one may own an interest in both the company that assesses and the company... Texas law
- The Certificate of Mold Damage Remediation (CMDR) Within 10 calendar days after a licensed project's stop date, the remediator must give the property owner the before-and-after photographs and a Certificate of Mold... Texas law
Browse by source
- EPA 402-K-01-001 Mold Remediation in Schools and Commercial Buildings Best practice
- 16 TAC Chapter 78 Texas Mold Assessment and Remediation Rules (TMARR) Texas law
- 25 TAC Chapter 295 (2007) Texas Mold Assessment and Remediation Rules, amended May 20, 2007 — HISTORICAL Historical
- Tex. Occ. Code Ch. 1958 Texas Occupations Code Chapter 1958 — Mold Assessors and Remediators Texas law
- IICRC S520 Reference Guide IICRC S520 Standard and Reference Guide for Professional Mold Remediation — Reference Guide Best practice
- CDC Mold Cleanup Guide Homeowner's and Renter's Guide to Mold Cleanup After Disasters Best practice
- OSHA SHIB 03-10-10 A Brief Guide to Mold in the Workplace Best practice
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