Check to see whether mold can be seen. Visible mold does not require any sampling.
Look for areas that have water damage or visible mold growth. A small amount of visible mold is enough evidence that mold remediation is needed.
Scrape a bit of mold into a plastic bag with a cue tip once any mold has been located. You can lift mold off a surface by applying clear tape and then pulling it away.
The mold will stick to the tape. Take pictures of the location where the mold is growing to include with the sample.
Take two samples of mold from each area you are testing.
Cut away pieces of the material that is infested with mold with your drywall knife or other tool. This may mean cutting off a piece of moldy carpet, drywall, or ceiling.
Place the piece in a clear plastic bag.
Send the mold or moldy material to a laboratory for mold analysis. The lab will be able to tell you what type of mold is growing in each sample.
Check with the public health department or EPA for recommended labs in your area.
Have a professional take an air sample if you smell mold but cannot visually locate it. The mold may be hiding, and the air test will measure the mold spores in the air.
Ensure that the air sampler takes several readings indoor as well as readings from out of doors. There may be a small amount of mold spores indoors because there is a large amount out of doors.
The EPA does not recommend air sampling as a way to determine whether mold is present.