test

relative humidity in a room or area (55% or higher), then you should strongly consider a dehumidifier. To determine the relative humidity, you will need a relative humidity sensor, also known as a moisture meter or hygrometer (Relative Humidity Sensor Buying Guide).

If you experienced severe flooding or a water leak, then you want to remove or pump out the standing water, followed by drying the area. If the area is really wet, you will want to use fans and dehumidifiers (What to look for in a dehumidifier). You may also want to move wet items away from walls and off floors.

The quicker you address the problem, the less extensive the damage will be since it may only take 24-48 hours for toxic mold to germinate and grow. Prompt remediation of contaminated areas and materials should be the primary response to water intrusion and indoor fungal growth.

Finding Mold Growth
Preventing Mold Problems

2. Minimize Dust and Seal Off Area (Negative Pressure)

Before you begin cleaning and removing the mold, it is critical to make sure that you take measures to prevent the mold spores from spreading to other areas of the house or building. Since mold spores will likely be stirred, becoming airborne during the cleaning process, you need to properly contain each area being cleaned, while also minimizing dust (a primary means of transportation for mold spores).

Containment:

Each room or area should be cleaned separately, one at a time. Before cleaning each room or area, you should seal it off as best as you can. This will prevent the mold from disseminating to other areas of the home or building while it is being cleaned, since cleaning can disturb and stir up the mold, causing mold spores to become airborne.

Once they become airborne, they can spread to other areas to germinate and colonize, unless the area being cleaned is properly sealed. See Cleaning the Mold to find out how to avoid stirring the mold as it is being cleaned.

Properly sealing (or containment) of a room or area consists of using plastic sheeting sealed with duct tape to cover doorways, vents, and other openings to occupied areas of the home or building.

If possible, you should place an exhaust fan next to an open (or partially open) door or window that is open to the outdoors. This will create negative air pressure, which will direct