GB/T 5275.7-2025 Active National standards

GB/T 5275.7-2025 Gas analysis—Preparation of calibration gas mixtures using dynamic methods— Part 7:Thermal mass-flow controllers

Publish Date: 2025-10-05 Implement Date: 2026-05-01 For services related to genuine standard inquiry, procurement, translation, and other related services in China, please Contact Us

Price: $ 66

Download

Basic Information

Standard Code: GB/T 5275.7-2025

Standard Type: National standards

Standard Status: Active

is_force_gb: no

CCS Name: Industrial gases and chemical gases

ICS Name: Industrial gases

Publish Date: 2025-10-05

Implement Date: 2026-05-01

Pages: 20 pages

Scope

GB/T 5275 is a series of documents describing various dynamic methods for preparing calibration gas mixtures. This document describes a method for continuously preparing calibration gas mixtures using a thermal mass flow controller and pure gases or gas mixtures. This document is applicable to gas mixtures in which the components do not react with the materials constituting the flow path of the thermal mass flow controller or auxiliary equipment.
The best achievable level of calibration gas mixtures prepared using the methods described in this document is as follows: the relative measurement expansion uncertainty (obtained by multiplying the standard uncertainty by the inclusion factor k=2) U is no greater than 2%.