Water vapor transmission method

Water Transport. Two methods of measuring water-vapor transmission rates (WVTR) ate commonly used. The newer method uses a Permatran-W (Modem Controls, Inc.). In this method a film sample is clamped over a saturated salt solution, which generates the desired humidity. Dry air sweeps past the other side of the film and past an infrared detector, which measures the water concentration in the gas. For a caUbrated flow rate of air, the rate of water addition can be calculated from the observed concentration in the sweep gas. From the steady-state rate, the WVTR can be calculated. In principle, the diffusion coefficient could be deterrnined by the method outlined in the previous section. However, only the steady-state region of the response is serviceable. Many different salt solutions can be used to make measurements at selected humidity differences however, in practice,... [Pg.500]

ASTM, Standard Test Methods for Water Vapor Transmission of Materials, ASTM E96/E96M-05, American Society for Testing and Materials, West Conshohocken, PA, 2005. [Pg.1152]

ASTM E96,2000. Standard test method for water vapor transmission of materials. [Pg.362]

Water Transport. Two methods of measuring water-vapor transmission rates (WVTR) are commonly used. The newer method uses a Permatran-W (Modern Controls, Inc.). The other method is the ASTM cup method. [Pg.175]

A gravimetric method is often used for the measurement of water vapor permeability. The water vapor transmission rate (WVTR) according to this method is the amount of water vapor in g that permeates in 24 hours under standard test conditions (temperature, air relative humidity, water vapor sorbant) through aim2 sample surface area. The method measure a flux and not a permeability coefficient. [Pg.262]

Test Methods. Tests for water repeUency of concrete and masonry have been described by several authors (72,94). The National Bureau of Standards (NBS) evaluated fifty-five clear water repeUents for masonry surfaces (95). Performance tests included water absorption, water-vapor transmission, resistance to efflorescence, change in appearance, and durability to accelerated and outdoor weathering. More recently, the National Cooperative Highway Research Program conducted a study of several organic and sihcone water-repeUent treatments. The results are communicated in Report 244 (96). The testing procedure used in this study is now a popular method for evaluating water-repeUent treatments on concrete. [Pg.311]

Both of these methods may be used to calculate permeability, permeance, and water vapor transmission rate (WVTR). ASTM C 355, formerly used for rigid foams, has been discontinued and replaced by ASTM E 96. [Pg.388]

ASTM E-90 Standard Test Method for Water Vapor Transmission of Materials, 8 pp (Comm C-16)... [Pg.417]

ASTM E 96, Standard methods of test for water vapor transmission of materials in sheet forms, Annual Book of ASTM Standards, American Society for Testing and Materials, Philadelphia, 2001. [Pg.419]

The permeability coefficient, P, combines the effects of the diffusion and solubility coefficients. The barrier characteristics of a polymer are commonly associated with its permeability coefficient values. The well-known relationship P = DS holds when D is concentration independent and S follows Henry s law. Standard methods for measuring the permeability of organic compounds are not yet available. ASTM E96 describes a method for measuring the water vapor transmission rate. ASTM D1434 describes a method for the determination of oxygen permeability. [Pg.90]

Dish method for determining water vapor transmission rate... [Pg.366]

BS 4370, Part 2, Method 8 is related to ISO 1663. 1981 [25] and describes the determination of water vapor transmission rate (pg/(nr s)), water vapor permeance (ng/(m s Pa)) and water vapor permeability (ng/(m s Pa) for rigid cellular materials that have thicknesses of between 10 mm and 70 mm. The first two properties are specific to the specimen thickness, whereas the permeability is a property of the material if this is homogeneous. A table is included in this British Standard giving conversion factors for all three properties. The method described is suitable for materials having a water vapor transmission rate of between 200 to 3000 pg/(m" . s). [Pg.384]

ISO 2528 (1995), Sheet materials—Determination of water vapor transmission rate Gravimetric (dish), method. [Pg.759]

ASTM F1249 (1990), Test method for water vapor transmission rate through plastic film and sheeting using a modulated infrared sensor. [Pg.760]

ASTM D1653, Standard test methods for water vapor transmission of organic coating film, in Annual Book of ASTM Standards, vol. 06.01, ASTM International, 100 Barr Harbor Drive, West... [Pg.578]

Water-Vapor Transmission. Primary Film Test Method ASTM E96. The primary test method for the determination of water-vapor transmission through plastics less than 32 mm thick is ASTM E96. (See Fig. 4.) There are two basic methods the Desiccant Method and the Water Method. Agreement between the two methods should not be expected. The method selected should be the one which most nearly approaches the conditions of use. [Pg.5]

Desiccant Method A desiccant covered by the film to be tested and placed in a humid chamber. Moisture from the chamber permeates the film and is picked up by the desiccant. After a measured period of time the test dish is reweighed and the water vapor transmission rate (WVTR) of the material is calculated. [Pg.5]

Water Vapor Transmission Rate (WVTR) Through Plastic Film and Sheeting Using a Modulated Infrared Sensor. Primary Film Test Method ASTM F1249. A procedure for determining the WVTR through flexible barrier materials, film, and sheet up to 3 mm in thickness is known as ASTM FI249. [Pg.6]

ASTM D96 (Discontinued Test Method) Standard test method for determining water vapor transmission of materials such as paper, plastic film and sheeting, fiberboards, wood products, etc., that are less than 31 mm in thickness. Two basic methods, the Desiccant Method and the Water Method are used. The specimens have either one side wetted or one side exposed to high humidity and another to low humidity. In the Desiccant Method, the... [Pg.184]

ASTM E398 Standard test method for the determination of water vapor transmission rate of sheet materials with at least one side being hydrophobic, such as plastic film, by a rapid dynamic method. The specimen is mounted between two chambers, one of known relative humidity... [Pg.187]

DIN 53122 A German Standards Institute (Deutsches Institut fuer Normen, DIN) standard test method for determining water vapor transmission of ffat materials such... [Pg.192]

JIS Z-0208 Testing methods for determination of the water vapor transmission rate of moisture proof packaging materials (dish method). [Pg.198]

The ASTM standard E96, Standard Test Method for Water Vapor Transmission of Materials provides a method for determination of water vapour transmission of materials such as paper, plastic films, other sheet materials, fibreboards, gypsum and plaster products, wood products, and plastics. This method has also been used for textiles for quite some time, although it does not simulate the actual wearing conditions of clothing. [Pg.46]

The weight (ISO 3801 1977), thickness (ISO 5084 1996), porosity and air permeability (ISO 9237 1995) of textile auxiliary walls were studied. Thermal resistance (Skin Model, ISO 11092 1993) and water vapor transmission rate (Dish Method Test, BS 7209 1990) tests were performed for heat and mass transfer properties [55—59]. [Pg.439]

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