Questions From The Field

Nov 22, 2017

During one of my recent inspections, a client presented me a list of questions after the assessment. I often encounter these questions in the field, so I picked out some of the best questions and I am providing the answers below.

Q1. Is everything in a room where mold spores are present assumed to have mold spores?

A1. Mold spores are everywhere and under normal conditions are generated in the outdoor air. They typically settle over time and are a common component of house dust. If there is an elevated spore count in a room, there will likely be additional spores settling on the contents in the affected room, joining the normal, background spores already on the surface.

Q2. How do I decide which items can be kept vs what can be cleaned vs what must be thrown away?

A2. If the items do not sustain mold growth, it can be cleaned and/or HEPA vacuumed to remove settled spores. If the item is sustaining mold growth and is a porous material, it should be discarded. If the item is sustaining mold growth and is non-porous, the item can be wiped clean.  If the item is wood and is sustaining mold growth, we generally recommend roughing the surface using a wire brush or sandpaper to remove the mold.

Q3. When do I clean my air ducts?

A3. Currently, the EPA does not recommend routine cleaning under most circumstances. The reason is that there is not enough concrete evidence showing that duct cleaning may improve air quality. However, duct cleaning should be performed if visible mold is seen in the ducts or other HVAC components.

Q4. Under what conditions do mold spores grow and multiply?

A4. Think of spores as being like seeds of a plant. Spores grow when there is adequate moisture and a nutrient source. Adequate moisture can come from flood water, exterior moisture intrusion, condensation and elevated humidity. Nutrient sources from mold are commonly dust, drywall’s paper facing, and wood.

Q5. What is the relative value of ERMI tests when compared with air tests?

A5. ERMI tests give insight into historical mold activity, whereas air samples tell current conditions. Because of this difference, ERMI tests and air samples running concurrently may yield vastly different results. Please note that the EPA currently recommends the ERMI tests for research purposes only.  We can still perform ERMI testing, but we do it in conjunction with a more traditional mold inspection.