The presence of humidity within a structure is often among the first direct causes or the trigger for many forms of degradation. Proper assessment of humidity is also essential for all those involved in laying coverings of any kind, as well as woodworking. The range of instruments distributed by PASI aims to satisfy any requirement with specific instruments for each individual application or modular and expandable ones. Humidity meters (hygrometers and moisture meters) are pocket instruments that enable immediate assessment of the water content inside a structure quickly and in a completely non-destructive manner on all types of material (plaster, concrete, brick, wood). Systems are also offered for continuous measurement of environmental parameters, suitable for monitoring any kind of internal environment.