Water vapor transmission rate (WVTR) of films and sheeting
Determination of the water vapor transmission rate (WVTR) according to standard ASTM F1249. WVTR describes the amount of water vapor that passes through a material or substance over a set period of time. It is an important indicator in food contact materials, as an effective moisture barrier is critical to keeping food fresh and preventing it from spoiling. Two samples per material are measured simultaneously to ensure the reliability of the measurement. The results are expressed as g/m2/day. Please disclose the desired temperature (from 18 to 40°C) and the desired relative humidity (from 20% to 100%) when placing the order. This measurement is applicable for film and sheeting materials with WVTR values between 0.001 and 2400 g / m2 / day.
More information about the method family:Water vapor transmission rate (WVTR)
- Suitable sample matrices
- Films of different materials and coated surfaces such as cardboard. Surfaces of the material needs to be smooth in order to get trustworthy results. Maximum thickness 2.5 mm. The expected WVTR value should be between 0.001 and 2400 g/m2/day.
- Minimum sample amount
- At least three sheets of the material are needed. Minimum sheet dimensions 10 x 10 cm, but preferably 20 x 20 cm to ensure optimal quality.
- Typical turnaround time
- 3 weeks after receiving the samples
- Detection limit
- 0.005 to 2400 g / m2 / day
- Quality system
- Accredited test method
- Device families
- Method expert