Asbestos Testing During Mold Remediation

Aug 30, 2018

After mold has been discovered, the primary concern of the property owner is to have remediation. One potential hazard that is often overlooked is the presence of asbestos in the materials that are being remediated. While the EPA has created the RRP Rule (Renovation, Repair, and Painting) to educate contractors about accidentally disturbing lead paint, there is no such rule in regards to asbestos.

Common Remediation Methods

The general rule of the thumb of mold remediation is to physically remove the mold growth. This is usually done by the following methods: cutting out and removing porous materials (e.g. drywall), wire brushing or using sandpaper on semi-porous materials (e.g. wood or some forms of plaster), or wiping down and HEPA vacuuming non-porous surfaces (e.g. concrete). While wood and concrete typically are not associated as asbestos-containing materials; drywall and plaster are. In the haste of removing mold-damaged materials, a contractor may be spreading asbestos fibers throughout the property.

Asbestos Containing Materials and Remediation

Asbestos-containing materials can be divided up into two categories; friable and non-friable. Friable refers to materials that can be crumbled into a powder with hand pressure. Drywall and plaster both meet the criteria for friable. Plaster, drywall, and associated tape & joint compound may contain asbestos in buildings constructed before the late 1970s. Improper removal of asbestos-containing materials by non-licensed asbestos professionals may lead to an accidental release of asbestos fibers.

Remediation Considerations

Much mold remediation and professional drying is done without formal containment and negative air pressures.  Certainly disturbing asbestos in these situations is a hazard to both workers and occupants. But what if the mold or drying work is done with proper engineering controls?  While an argument can be made that there is little health risk for asbestos if mold remediation is being conducted in a containment area under negative air pressure similar to asbestos abatement, there are still concerns present The first concern with this argument is mold remediation personal protection equipment (PPE) is different than asbestos PPE. Many mold remediation contractors wear a half face N95 respirator, while many asbestos workers wear full-face P100 respirators which provide more respiratory protection. Another issue is that if asbestos is unknowingly disturbed, there is no ongoing air quality monitor that can determine what is the airborne concentration for asbestos fibers. Mold clearance air samples are not able to determine if asbestos is airborne. Lastly, while mold debris can be disposed of as general waste, there are special protocols that taken with asbestos debris which determine how the material is contained and which landfill it is taken to.


When dealing with older homes and buildings, it is imperative that mold remediation contractors have a suspect material tested by a licensed asbestos inspector such as Indoor Science prior to remediation activities as it may lead to an accidental asbestos release. By disturbing an asbestos-containing material, the contractors may be held legally liable for any damages caused and may face fines and penalties from local, state, and federal agencies.

Furthermore, property owners should perform an inspection to know which materials contain asbestos.  If there is an unexpected emergency such as a flood or mold problem, they will know to warn any contractors to avoid asbestos fibers being spread throughout.