How to Make a Mold Test Kit

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Mold can seriously affect human health. The quantity of mold, type of mold present and individual susceptibility are all factors related to the level or degree of health risk. Mold-test kits are available that determine the presence of mold and identify what type of mold is present. You can make a mold test kit yourself using a few simple items.

How to Make a Mold Test Kit

Place the petri dish on a flat surface. Put clear tape inside the dish, with the sticky side up. Place enough tape to span across the dish. The tape will catch any mold spores in air. Mold releases spores as a way of migrating. When the spores come into contact with water or moisture, they are able to form new mold colonies.

Place a second petri dish in the air duct above the return air vent. Make sure the inside is lined with tape just like the previous step. Any mold spores traveling inside the ventilation systems will pass over the dish and cling to the tape.

Perform an analysis. After allowing the petri dishes to sit overnight, place them under a microscope. If you know what mold looks like, you can identify its presence in the air. Dust particles are likely to show up in the petri dish also, so be certain not to confuse the two. If you cannot or prefer not to do a technical analysis, there are companies you can send collected air samples to. They will perform the analysis and provide information on mold presence and type.

Perform a visual inspection. Many mold test kits will ask you to take a sample of the suspected surface mold with a swap. This is so the mold can be identified for any toxic types like Stachybotrys and Aspergillus-Niger. It also will determine if the sample is a mold or a mildew, which are often confused since both molds and mildew prefer warm and moist environments like bathrooms. Molds, however, typically are black, green, red or blue in color. They can also appear fuzzy or slimy depending on the type. Mildew is usually gray or white and can be powdery or downy. A simple visual inspection should indicate whether the surface fungi is a mold or mildew.

Follow the CDC recommendation on testing. The degree and type of mold growth and individual susceptibility make it impossible to determine acceptable levels. This is why the Centers for Disease Control (CDC) state that sampling and culturing are not reliable methods of determining health risk. Testing may be subjective and the CDC recommends any mold discovered should be removed immediately to minimize health risk.


Having a laboratory perform a mold test for you can be quite expensive.