Våttnemåling

Våttnemåling is a term used in Norwegian to describe methods for determining the moisture content of a material or environment. It covers measurements of water content in soils, wood, concrete, foodstuffs and other porous materials, and is important for assessing stability, processing efficiency, and quality control.

Moisture content can be expressed as gravimetric moisture content (the ratio of the mass of water to the mass of dry material) or volumetric moisture content (the volume of water per total volume). Temperature, salinity, and material heterogeneity influence results.

Common methods include gravimetric (loss-on-drying by oven at 105–110 C), which is a reference method; dielectric or capacitance methods using sensors or time-domain reflectometry for in-situ measurements; electrical resistance methods using probes; and, in some cases, nuclear techniques such as neutron moisture gauges, which are more specialized and require licensing. In timber and construction, handheld moisture meters using resistance or capacitance are widely used for quick checks.

Applications span agriculture for irrigation planning; construction and concrete drying and quality control; forestry for drying timber; and the food industry for product quality and process monitoring.

Standards and accuracy: ISO, ASTM and regional standards exist for specific materials and methods. Results can be affected by temperature, salinity, material composition, and calibration; proper sample preparation and calibration improve reliability.

See also: Moisture content; Oven-drying method; Time-domain reflectometry; Soil moisture sensors.