Knob and tube wiring is an older type of electrical wiring that's no longer used and generally not considered safe. However, some homes still have it, or may have a knob and tube wiring system that was incorrectly modified or rigged to work with a modern electrical system. Knob and tube wiring may contain asbestos insulation, but the only way to know is to have the material professionally tested.

Since the EPA partially banned asbestos in 1989, it is no longer used to manufacture new siding in the United States; production had largely ceased by the early 1980s. Many other countries, such as Canada, Iceland, and Denmark, also have bans on asbestos. However, asbestos siding is still present in many homes built before the late 1980s. The only definitive way to know if your siding contains asbestos is to have it professionally lab-tested.

Unfortunately, asbestos is not easily identified and can often be hidden in plain sight in your home. While it can look like fluffy fibers, tiny pieces can also appear in materials like plastic or cement, making it impossible to identify on your own properly.

Plus, since asbestos is so dangerous when disturbed, you should never root around to try and find it. This job is best for a professional who can test for the material properly.

Because of the danger of inhaling asbestos fibers, figuring out through testing whether your popcorn ceiling contains asbestos is definitely worth it. If the popcorn ceiling texture has asbestos, remove it as soon as possible to keep your family safe. Any home built in or before the 1980s that has popcorn ceilings could have asbestos, necessitating testing. Asbestos carries several health risks for people who inhale it, including the increased chance of developing lung cancer in the future.