This article reviewed the methods that are available to test thermal properties of various insulating materials. These methods can fall under one of two categories: steady state techniques and non-steady (transient) techniques. The transient plane source (TPS) method is classified as a non-steady state technique. The TPS sensor is a round piece of engraved nickel that conducts electrical currents and is covered with a coating of Kapton, Mica or Teflon. ...