Fiberglass pipe insulation can be installed on exhaust pipes, though with caution. Basic fiberglass insulation has a risk of melting when being exposed to hot temperatures. That said, ASJ Max Fiberglass Insulation has a max operating temperature rating of 1,000°F. Most exhaust pipes rarely reach or exceed this temperature, making this type of insulation appropriate. However, it should be noted that the paper jacket of fiberglass insulation is flammable so these should be kept away from any industrial operations that include an open flame.