Mold Remediation Certification Practice Exam

What level of water activity (aw) is required for Stakey to grow?

1. Greater than 0.5

2. Less than 0.3

3. Exactly 0.7

4. Greater than 0.9

The correct answer is: Greater than 0.9

Stachybotrys, commonly known as "black mold," requires a high level of water activity for growth, specifically greater than 0.9. Water activity is a measure of the availability of water for microbial growth, and molds typically thrive in environments where water activity is sustained at higher levels. Conditions that provide a water activity above 0.9 are conducive to mold spores becoming metabolically active and generating the necessary conditions for growth, such as hyphal development and spore production. This is crucial, as molds are reliant on moisture to absorb nutrients and reproduce. The other options suggest lower levels of water activity, which are unfavorable for Stachybotrys growth. Molds that can thrive in those lower ranges tend to be different species that are more tolerant of dry conditions, whereas Stachybotrys is particularly associated with environments that are wet or damp. Thus, understanding the specific requirements of Stachybotrys helps in implementing effective mold remediation strategies by managing moisture levels in affected areas.