CMI Cheat Sheet 2026

The 30 highest-yield CMI facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. According to the IICRC S520 standard, what are the three primary remediation levels based on contamination area? → Level 1 (≤10 sq ft), Level 2 (10–100 sq ft), Level 3 (>100 sq ft)
2. A carbon dioxide concentration above what level (ppm) in an occupied space typically indicates inadequate fresh air ventilation? → 1,000 ppm
3. Which type of respiratory protection is appropriate when spraying biocide solutions in a confined mold-contaminated space? → Full-face respirator with combination OV/P100 cartridges
4. If post-remediation verification sampling shows mold levels higher than outdoor reference samples, what is the appropriate action? → Perform additional remediation and cleaning, then re-test
5. Post-remediation clearance testing is performed by which party to maintain objectivity under IICRC S520? → An independent third-party assessor not affiliated with the remediation company
6. Mold growth in an air handling unit (AHU) is most commonly found in which location first? → The evaporator coil and condensate drain pan where moisture accumulates
7. What instrument is commonly used to measure airborne particulates? → Particle counter
8. An inspector finds standing water in the condensate drain pan of a rooftop unit. What is the primary corrective action? → Clear the drain line obstruction and slope the pan correctly to eliminate standing water
9. When documenting a mold finding in an inspection report, the inspector should describe the affected area using: → Specific location, approximate square footage, substrate type, and visual characteristics
10. What is the principal concern with glucan (fungal cell wall component) in water-damaged buildings independent of mycotoxin production? → Beta-glucans can trigger inflammatory responses in the lungs even from dead mold cells
11. Why is it important to collect outdoor air samples during an indoor mold inspection? → To compare with indoor spore levels for evaluation
12. Which NADCA standard provides guidelines for the assessment and cleaning of HVAC systems suspected of mold contamination? → NADCA ACR (Assessment, Cleaning and Restoration of HVAC Systems)
13. Which level of protective suit is recommended during mold remediation work in a heavily contaminated area (>100 sq ft per IICRC S520 large remediation)? → Disposable coveralls (Tyvek or equivalent) with hood and booties
14. A P100 cartridge on a half-face air-purifying respirator filters particles with what efficiency rating? → 99.97% at 0.3 microns (HEPA-equivalent)
15. A mold inspection report prepared under New York State mold licensing law (Article 32, Labor Law) must be signed by a: → Licensed Mold Assessor holding a New York State license
16. According to NADCA standards, what is the primary trigger for recommending HVAC duct cleaning related to mold? → Confirmed microbial growth (mold or bacteria) inside the duct system or on HVAC components
17. A moisture meter reading above what percentage in wood framing is generally considered a threshold indicating conditions favorable for mold growth? → 19%
18. What is the primary route of human exposure to mold-related health hazards in a contaminated building? → Inhalation of spores and fragments
19. What is the primary purpose of a mold inspection report? → To record inspection findings and recommendations
20. A flat roof with interior drains begins showing mold growth on the ceiling decking of the top-floor offices. The most likely cause is: → Roof drain clogs causing ponding water and eventual infiltration
21. Which mold species is most commonly associated with invasive aspergillosis in immunocompromised patients? → Aspergillus fumigatus
22. Which piece of equipment is used to create and maintain negative air pressure inside a mold remediation containment area? → HEPA-filtered negative air machine (NAM)
23. What tool is commonly used to detect hidden moisture? → Moisture meter
24. Which HVAC filter MERV rating is the minimum recommended to capture most fungal spores (3–10 microns) in a commercial building? → MERV 11–13
25. In building science, the 'dew point' is defined as the temperature at which: → Relative humidity reaches 100% and condensation begins on a surface
26. Why is indoor air quality (IAQ) important to assess? → To ensure occupant health and comfort
27. Which grading condition at the exterior of a foundation is most directly associated with chronic basement water intrusion and basement mold problems? → Negative grade sloping toward the foundation, directing surface runoff against the wall
28. What indoor relative humidity range is recommended by the EPA to minimize mold growth in residential buildings? → 30–50%
29. What condition is ideal for accurate air sampling results? → After 12 hours of closed conditions indoors
30. Why is building science important in moisture control? → It helps prevent moisture-related problems