Tiêu chuẩn quốc tế

• Số hiệu / Standard Number: ASTM F1249-13
• Năm ban hành / Publication date: 2013
• Tình trạng / Status: W - Hết hiệu lực
• Tên tiếng Anh / Title in English: Standard Test Method for Water Vapor Transmission Rate Through Plastic Film and Sheeting Using a Modulated Infrared Sensor
• Chỉ số phân loại Quốc tế (ICS) / By field: 83.140.10 - Màng và tấm
• Số trang / Page: 6

Phạm vi áp dụng / Scope of standard

1.1 This test method covers a procedure for determining the rate of water vapor transmission through flexible barrier materials. The method is applicable to sheets and films up to 3 mm (0.1 in.) in thickness, consisting of single or multilayer synthetic or natural polymers and foils, including coated materials. It provides for the determination of (1) water vapor transmission rate (WVTR), (2) the permeance of the film to water vapor, and (3) for homogeneous materials, water vapor permeability coefficient.

Note 1-Values for water vapor permeance and water vapor permeability must be used with caution. The inverse relationship of WVTR to thickness and the direct relationship of WVTR to the partial pressure differential of water vapor may not always apply.

1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.