Several options are available to measure these temperatures. One option is to use sensors based on semiconductor technologies. Another option is to qualify the platinum resistance thermometers currently used in industry (e.g. PT1000) also for this range by suitable modifications. Until now, the corresponding DIN standard EN 60751:2009, has a validity range down to -200°C, which also corresponds to the use of liquid nitrogen. Although platinum resistance thermometers corrode little and are considered reliable, temperature fluctuations can lead to mechanical stresses in the sensor and, with permanent continuous measurements, to inaccurate readings.