Mold Containment

If mold is discovered in your home, then it’s time to call in professionals to contain and remediate the area. The exact procedure will vary based on the size of the contaminated area but there are certain general guidelines that apply to all mold containment.

First, it’s crucial to isolate the area with flame retardant plastic sheeting. This will help prevent the spread of mold to other areas of the home. Another important way to isolate the room is to use a negative air machine. A negative air machine works by drawing the contaminated air into the machine, running it through a filter, then expelling the air to ducting that is connected to the exterior of the contaminated area. By creating a negative pressure in the area, you can prevent the flow of contaminated air into clean areas. You can tell if the room is under negative pressure, when any coverings blow inwards instead of outwards.

Additionally, an air scrubber is useful to reduce the concentration of mold and clean the air. As opposed to a negative air machine, an air scrubber is not connected to ducting. An air scrubber draws in the contaminated air and pushes it through the filtration system, then returns clean air into the room. The same machine can often be used as both a negative air machine and an air scrubber, depending on the set up.

In addition to machines, mold remediation jobs will require personal protective equipment (PPE). PPE is necessary to minimize a person’s exposure to mold, as they are remediating an area. Various steps in the remediation process can actually stir up mold and cause it to become airborne. For instance, stripping damaged wall paper or breaking up mold on wall board could increase the amount of mold spores in the air.

The amount of personal protective equipment required will vary based on the severity of the mold. For even the smallest jobs (less than 10 square feet), you will need goggles, a N-95 respirator, and gloves. The goggles used during remediation cannot have open holes and should be able to keep out small particles. The N-95 respirator will provide protection for your nose and mouth, as well as, filter out the majority of airborne particulates. It’s recommended that the gloves extend to the forearm for extra protection. Additionally, the material of the gloves should be changed depending on the chemicals you are using for remediation. When you’re using a strong cleaning solution, your gloves should be made from materials such as neoprene versus an ordinary household cleaning gloves.

The Environmental Protection Agency divides mold remediation into two main categories- limited containment and full containment. A limited containment is necessary for a situation with 10 to 100 square feet of mold contamination. An area larger than 100 square feet of contamination would need a full containment. As the name implies, a full containment is more aggressive since the larger the area, the higher the risk of mold spreading.

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Limited Containment- Preparing the Space

For a limited containment (10-100 square foot area), you will first need to enclose the affected area in polyethylene sheeting. The polyethylene needs to be fire retardant, and at least 6 millimeter in thickness. You can secure the sheeting to the floor and ceiling using duct tape or epoxy. Alternatively, you can also create a frame out of steel or wood studs. For entry into the space, you can will need to slit the polyethylene in the doorway and attach a flap of polyethylene on the outside covering the slit. Any vents or heating grills in the area will also need to be sealed.

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Limited Containment- Personal Protective Equipment

While working in a limited containment, people will need to wear disposable paper overalls and gloves. Furthermore, a respirator and eye protection (if not provided by the respirator) is required. The respirator can be a half face (doesn’t protect eyes) or full face model, as long as it includes P100 filter cartridges. This will give you the protection of inhalation and exhalation valves to ensure people aren’t breathing in mold.

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Full Containment- Preparing the Space

If the situation calls for a full containment (over 100 square feet), the space will require a little more attention. Just like with limited containment, make sure any vents and grills are covered. You will still need to enclose the area with polyethylene sheeting, but this time a double layer will be necessary. In addition, the entry process is different, since you need a decontamination chamber to get in and out of the area. The decontamination chamber is a simply an area with doors that separates the moldy rooms from the clean rooms. Inside the decontamination chamber is where people can put on PPE, as well as, dispose of it in sealed bags when exiting. This applies to all PPE except the respirator, which will need to be worn until back in the clean area. The door entering and exiting the decontamination chambershould be slits covered by flaps on the exteriors, similar to what is used in a limited containment.

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Full Containment- Personal Protective Equipment

As you would expect, more PPE is necessary when involved with a full containment. People working in the containment will need to wear disposable full body clothing, plus gloves, head gear and foot coverings. The body covering should be made of a breathable material with all possible gaps, such as around the ankles, sealed. When dealing with a full containment, it’s also necessary to use a full face respirator with HEPA filter.

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May, Jeffrey C., and Connie L. May. Jeff Mays healthy home tips: a workbook for detecting, diagnosing, & eliminating pesky pests, stinky stenches, musty mold, and other aggravating home problems. Baltimore, Johns Hopkins University Press, 2008.
“Mold Course Chapter 6:” EPA, Environmental Protection Agency, 21 Feb. 2017, Accessed 21 Sept. 2017.