The Environmental Protection Agency (EPA) banned the use of asbestos pipe insulation in certain applications in 1975. It released further bans in 1989 and 2019. While asbestos pipe insulation was common from the 1930s to 1970s, its use fell off after the 1970s due to public concern and the EPA's actions.

Asbestos siding can be dangerous, but it doesn't necessarily pose a health risk if it's in good condition and left undisturbed. The danger comes from inhaling asbestos fibers, which can be released if the siding is damaged, deteriorating, crumbling, or disturbed during remodeling or repairs. Exposure to these airborne fibers can cause serious, life-threatening diseases like asbestosis (lung scarring), mesothelioma (an aggressive cancer), and other lung cancers.

If your asbestos siding is intact, the general recommendation is to leave it alone. However, if it's damaged or you plan to renovate, it's crucial to handle it safely. Due to the significant health risks and the difficulty of containing the fibers, it is not recommended to perform any asbestos work yourself. Instead, you should hire a professional asbestos removal company to inspect, repair, encapsulate, or remove the material. The presence of asbestos can also negatively impact your property's value.

If you own a stereo microscope, you should be able to see the fibers. The stereo microscope often can perform magnification up to 50x. But unless you have experience viewing asbestos fibers, you may not know exactly what you are seeing. Some fibers are curly, while others are long and straight. Blue, brown, white, and gray colored fibers are all possible.

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.