Tiêu chuẩn quốc tế

• Số hiệu / Standard Number: ASTM D4298-95(1999)
• Năm ban hành / Publication date: 1999
• Tình trạng / Status: W - Hết hiệu lực
• Tên tiếng Anh / Title in English: Standard Guide for Intercomparing Permeation Tubes to Establish Traceability
• Chỉ số phân loại Quốc tế (ICS) / By field: 17.020 - Ðo lường và phép đo nói chung
• Số trang / Page: 3
• Phạm vi áp dụng / Scope of standard: 1.1 This guide covers two procedures for establishing the permeation rate of a permeation tube and defining the uncertainty of the rate by comparison to National Institute of Standards and Technology's Standard Reference Materials (SRM). 1.2 Procedure A consists of a direct comparison of the permeation rate of the device undergoing calibration with that of an SRM. 1.3 Procedure B consists of a gravimetric calibration process in which a certified permeation tube is used as a quality control for the measurements. 1.4 Both procedures are limited to the case where a suitable certified permeation device is available. 1.5 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. (See 8.2 on Safety Precautions.)