Moisture measurement in gases (and air) is a minority subject area and many first time buyers of humidity instruments - dewpoint hygrometers, portable dewpoint hygrometers and other moisture meters in air and gases - even those with excellent technical qualifications, find they are not well prepared to make the right choice of instrument for their application. In our Humidity School we give you a thorough grounding in definitions, units and measurement methodology to enable you to make the right product choice.