While many systems operate at a continuous temperature, it is important to recognize and take into consideration any system temperature spikes and thermal cycling if they exist.
When the system temperature fluctuates quickly due to spikes or thermal cycling, the sealing device must react to any movement that occurs in the application related to expansion, contraction, and change in internal pressure.
Cryogenic conditions must also be properly handled, as most materials (in this case, sealing devices) have a low-temperature limit where the material becomes brittle. If this occurs, the product may crack or break and result in premature failure.