Introduction to ASTM E96 Standard

The ASTM E96 standard is utilized for testing the water vapor permeability of various materials including paper, plastic films, sheet materials, fibre-boards, gypsum and plaster products, wood products, and plastics. It outlines two primary testing methods: the desiccant method and the water method.

ASTM E96 Desiccant Method

In the desiccant method, a test dish containing a desiccant is used. The dish must have enough space to allow for shaking to mix the desiccant, which is necessary at each weighing. The test specimen is sealed to the open mouth of the dish, and the rate of water vapor movement is determined by periodically weighing the test dish.

ASTM E96 Water Method

The water method involves a dish containing distilled water. Water vapor permeates through the specimen into a controlled atmosphere, and periodic weighing of the test dish provides the necessary values.

Considerations for ASTM E96 Test Method

It is important to note that values obtained under different test conditions may not be equivalent. Therefore, it is crucial to select test conditions that closely match the conditions of use. Both the desiccant and water methods are generally referred to as gravimetric methods.

Equipment Example

The Saicheng WPT-301B Water Vapor Permeability Tester is an example of equipment manufactured in accordance with ASTM E96 and ASTM D1653 standards, utilizing the gravimetric method to measure the water vapor permeability of materials.