National Physical Laboratory

Humidity generators

Humidity generators 

Calibration of humidity generators

NPL calibrates humidity generators by comparison against transfer standards, or directly against NPL's own primary standard generators. The calibration range offered is the same as for calibration of hygrometers. 


Hygrometers of all types in terms of relative humidity, dew point, mixing ratio or other humidity quantities

Humidity calibration salts

Design and build of humidity generators

NPL is also able to specify, design and build humidity generators to order, meeting the range and uncertainty required by top national laboratories, or to lesser requirements specified by customers.

This draws on NPL's expertise developed over many years of building the UK's primary dew-point and relative humidity generators, as well as equipping them with every aspect of supporting instrumentation, software, and documented operating procedures.

Installation, commissioning, complete system validation, uncertainty analysis, user training, measurement audits, and preparation for accreditation can all be provided, if required.


Customer Service tel: +44 20 8943 8681

Last Updated: 11 Dec 2017
Created: 15 Jul 2010


Please note that the information will not be divulged to third parties, or used without your permission