Mold Identification and Assessment Flashcards

Which condition best describes the relative humidity level above which most indoor molds begin to grow?

Answer: Above 60%

Most indoor mold species begin to colonize surfaces when sustained relative humidity exceeds 60%, with growth accelerating above 70%.

What is the significance of finding Chaetomium species during a mold assessment?

Answer: It is a strong indicator of past or ongoing chronic water damage

Chaetomium thrives on wet cellulose and is rarely found outdoors in significant quantities, making its indoor presence a reliable indicator of water damage.

During visual inspection, what does 'efflorescence' on a concrete wall indicate regarding mold risk?

Answer: Water is migrating through the concrete, creating moisture conditions favorable to mold

Efflorescence is salt deposits left behind as water moves through concrete, indicating moisture intrusion that can support mold growth on adjacent organic materials.

What type of sampling should a mold assessor collect when mold is suspected inside a wall cavity without opening the wall?

Answer: Air sample from a small drilled hole into the cavity

Drilling a small hole and drawing air from within the cavity allows spore trap sampling to detect mold without destructive opening of the wall.

Which document provides widely referenced federal guidance on mold investigation and remediation in homes and buildings?

Answer: EPA Publication 402-K-02-003 'Mold Remediation in Schools and Commercial Buildings'

The EPA publication 'Mold Remediation in Schools and Commercial Buildings' is the primary federal guidance document for mold investigation and remediation practices.

When comparing Aspergillus and Penicillium spores under a microscope, why are they often reported together as 'Aspergillus/Penicillium'?

Answer: Their spores are morphologically identical and cannot be distinguished by standard microscopy

Aspergillus and Penicillium spores are indistinguishable by optical microscopy and are therefore grouped together in spore trap analysis reports.

What is the recommended action when a mold assessor finds visible mold growth covering more than 100 square feet?

Answer: It qualifies as a large contamination area requiring professional remediation per EPA guidance

EPA guidance classifies mold contamination exceeding 100 square feet as a large area requiring professional remediation with full containment protocols.