Utility Requirements
66 H157655_1_008
The maximum humidity in the lab depends on the room temperature. There are parts on or
near the NMR spectrometer and the magnet system (like the nitrogen heat exchangers)
which have temperatures of 14…16°C. When the room temperature is 25°C, with a humidity
of 80 %, the dew point of this air is at 21.3°C. This means condensation may build up at the
heat exchangers of the magnet and other parts like temperature units or shim coils.
Therefore we recommend a dew point of 14-16°C in the laboratory (for the magnet parts) to
avoid condensation at the location of cold parts. With a laboratory temperature of 17°C the
humidity can rise up to 67.7 % and with 25°C it will be only 41.4 %.
Temperature in
the NMR
laboratory
Maximum humidity for a dew point of
11 °C 12 °C 13 °C 14 °C 15 °C 16 °C
17 °C 67.7 % 72.4 % 77.3 % 82.5 % 88.0 % 93.8 %
18 °C 63.6 % 68.0 % 72.6 % 77.5 % 82.6 % 88.1 %
19 °C 59.7 % 63.8 % 68.2 % 72.8 % 77.6 % 82.7 %
20 °C 56.1 % 60.0 % 64.1 % 68.4 % 72.9 % 77.8 %
21 °C 52.8 % 56.4 % 60.2 % 64.3 % 68.6 % 73.1 %
22 °C 49.7 % 53.0 % 56.7 % 60.5 % 64.5 % 68.8 %
23 °C 46.7 % 49.9 % 53.3 % 56.9 % 60.7 % 64.7 %
24 °C 44.0 % 47.0 % 50.2 % 53.6 % 57.2 % 60.9 %
25 °C 41.4 % 44.3 % 47.3 % 50.5 % 53.8 % 57.4 %
Table8.4: Maximum Humidity in the NMR Laboratory
Conditions other than these may warrant the installation of an air conditioner with appropriate
humidity controls.