Indoor Air sciences CSMI Practice Exam

What is a common sign that microbial growth may be present?

1. Discoloration on walls

2. Excessive dust accumulation

3. Low indoor humidity

4. Strong chemical odors

The correct answer is: Discoloration on walls

Discoloration on walls is a common sign that microbial growth, such as mold or mildew, may be present. This discoloration often appears as patches of green, black, or brown spots and can occur in areas where moisture is prevalent, such as bathrooms, kitchens, or in spaces with water leaks. The presence of moisture is a key factor in microbial growth, and when combined with organic materials found in building materials and furnishings, it creates an environment conducive to growth. Identifying visible discoloration can prompt further investigation and remediation to prevent health risks associated with prolonged exposure to mold spores. The other options, while indicative of varying indoor air quality issues, do not specifically signal microbial growth. Excessive dust accumulation might suggest poor ventilation or cleaning habits, low indoor humidity can inhibit mold growth, and strong chemical odors are often linked to indoor pollutants rather than biological contaminants.