text: Hot water service piping can also be traced, so that a circulating system is not needed to provide hot water at outlets. The combination of trace heating and the correct thermal insulation for the operating ambient temperature maintains a thermal balance where the heat output from the trace heating matches the heat loss from the pipe.  Self-limiting or regulating heating tapes have been developed and are very successful in this application.
  A similar principle can be applied to process piping carrying fluids which may congeal at low temperatures, for example, tars or molten sulfur. Hit-temperature trace heating elements can prevent blockage of pipes.
  Industrial applications for trace heating range from chemical industry, oil refineries, nuclear power plants, food factories.  For example, wax is a material which starts to solidify below 70 °C which is usually far above the temperature of the surrounding air.  Therefore, the pipeline must be provided with an external source of heat to prevent the pipe and the material inside it from cooling down.  Trace heating can also be done with steam, but this requires a source of steam and may be inconvenient to install and operate.
  In laboratories, researchers working in the field of materials science use trace heating to heat a sample isotropically.  They may use trace heating in conjunction with a variac, so as to control the heat energy delivered.  This is an effective means of slowly heating an object to measure thermodynamic properties such as thermal expansion.