If a P Test reveals contamination, it’s important to start the Meth Decontamination process immediately. The sooner you address the issue, the less damage the contamination can cause to the property and its occupants. Taking swift action also helps avoid any legal issues, especially if you are renting out the property. If a P Test reveals contamination, it’s important to start the Meth Decontamination process immediately. The sooner you address the issue, the less damage the contamination can cause to the property and its occupants. Taking swift action also helps avoid any legal issues, especially if you are renting out the property.