MRS Building Materials & Mold Growth 5

Question 1

A remediator encounters mold growing behind a bathtub surround on the framing. The tile itself shows no mold. What is the most likely cause?

Accepted Answer

Grout failure allowing water to migrate behind the surround to the framing

Answer

Failed grout or caulk joints at tub/tile intersections allow splash and shower water to infiltrate behind the surround, saturating the framing and creating hidden mold conditions.

Question 2

Which material characteristic is described by the term 'hygroscopic' in the context of building materials and mold risk?

Accepted Answer

The tendency of a material to absorb and retain moisture from the surrounding air

Answer

Hygroscopic materials such as wood, drywall, and cellulose insulation absorb water vapor from humid air and retain it, raising their moisture content and making them prone to mold growth.

Question 3

What is the PRIMARY reason that window condensation on the interior glass surface contributes to mold on window frames?

Accepted Answer

Condensed water runs down onto the sill and frame, wetting wood or painted surfaces repeatedly

Answer

Condensation that forms on cold glass runs down to the sill and frame, repeatedly rewetting wood, paint, and caulk and providing sustained moisture that supports mold on these organic substrates.

Question 4

Which of the following correctly describes the relationship between stachybotrys chartarum and building materials?

Accepted Answer

It requires very high water activity and grows primarily on cellulose-rich materials with sustained wetting

Answer

Stachybotrys chartarum is a slow-growing, highly water-dependent mold that colonizes cellulose-rich materials such as paper-faced drywall and ceiling tiles only under conditions of prolonged and severe moisture exposure.

Question 5

When remediating mold on a concrete slab with vinyl composition tile (VCT) flooring, what hazard must be assessed BEFORE removal?

Accepted Answer

Asbestos content in pre-1980s VCT adhesive and tiles

Answer

VCT flooring and its adhesives manufactured before approximately 1980 frequently contain asbestos fibers, requiring asbestos assessment and potentially abatement before mold remediation can proceed.

(MRS) Mold Remediation Specialist Practice Test

(MRS) Mold Remediation Specialist Practice Test

MRS Building Materials & Mold Growth 5