CMI CMI Remediation Protocols & Post-Remediation Verification 1 — Questions and Answers
Question 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) (Correct answer)
- Level 1 (≤25 sq ft), Level 2 (25–200 sq ft), Level 3 (>200 sq ft)
- Level 1 (≤5 sq ft), Level 2 (5–50 sq ft), Level 3 (>50 sq ft)
- Levels are determined by mold species, not area
Correct answer: Level 1 (≤10 sq ft), Level 2 (10–100 sq ft), Level 3 (>100 sq ft)
IICRC S520 defines Level 1 as ≤10 sq ft (limited), Level 2 as 10–100 sq ft (mid-range), and Level 3 as >100 sq ft (extensive), with corresponding PPE and containment requirements.
Question 2: What is the purpose of establishing 'containment' during mold remediation?
- To prevent cross-contamination of mold spores to unaffected areas during the disturbance of mold growth (Correct answer)
- To keep remediation workers inside the work area at all times
- To allow biocides to reach higher concentrations within the work zone
- Containment is only required for Stachybotrys, not for other mold species
Correct answer: To prevent cross-contamination of mold spores to unaffected areas during the disturbance of mold growth
Containment barriers with negative air pressure prevent disturbed mold spores from migrating to clean areas of the building during remediation activities.
Question 3: What is the role of negative air pressure inside a remediation containment area?
- To ensure air flows from clean areas into the containment zone rather than from the contaminated zone outward (Correct answer)
- To increase the biocide concentration within the work area
- To reduce the need for PPE by containing spores to floor level
- Negative pressure is only relevant in hospital isolation rooms, not mold remediation
Correct answer: To ensure air flows from clean areas into the containment zone rather than from the contaminated zone outward
Maintaining negative pressure inside containment ensures that any air leakage travels inward (clean to contaminated) rather than outward, preventing spore migration to unaffected spaces.
Question 4: 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) (Correct answer)
- Standard box fan exhausting outward
- Central HVAC system set to maximum return
- Ozone generator
Correct answer: HEPA-filtered negative air machine (NAM)
A HEPA-filtered negative air machine exhausts air from the containment zone through HEPA filtration to the exterior, creating negative pressure while filtering out spores before discharge.
Question 5: According to best practices, should biocides (e.g., bleach) be used as the primary remediation method for mold on porous materials?
- No — biocides do not penetrate porous materials adequately; physical removal is required (Correct answer)
- Yes — EPA-registered biocides are the only compliant remediation method
- Yes — bleach kills all mold species and leaves surfaces permanently protected
- Biocides are only prohibited in residences, not in commercial buildings
Correct answer: No — biocides do not penetrate porous materials adequately; physical removal is required
On porous materials like drywall and wood, biocides cannot penetrate deeply enough to kill all mold; physical removal (cutting out and bagging) is the required remediation approach.
Question 6: What does 'post-remediation verification' (PRV) testing confirm?
- That the remediated area has been returned to a condition of normal fungal ecology comparable to an unaffected reference area (Correct answer)
- That 100% of mold spores have been eliminated from the entire building
- That all biocide residues have been removed from surfaces
- PRV is a legal requirement only in commercial buildings
Correct answer: That the remediated area has been returned to a condition of normal fungal ecology comparable to an unaffected reference area
Post-remediation verification confirms that the work area has been cleaned to a level of normal fungal ecology by comparing remediated area samples to outdoor reference and unaffected indoor reference samples.
CMI CMI Remediation Protocols & Post-Remediation Verification 1
According to the IICRC S520 standard, what are the three primary remediation levels based on contamination area?