Partners save 15% on every standard

Valid

GB/T 45954-2025General technical requirements for meteorological measurement standards — Air humidity (English PDF)

气象计量标准器通用技术要求空气湿度

Open the GB/T 45954-2025 preview as PDF

Preview — first pages of GB/T 45954-2025 (full document: 15 pages)

This is a limited preview

Buy now to download the full PDF (15 pages)

Issued by

SAMR; SAC

Level / Type

National · Recommended

Issue date

August 1, 2025

Implementation date

February 1, 2026

Scope

GB/T 45954-2025 is the English-translated version of 气象计量标准器通用技术要求空气湿度.

GB/T 45954-2025 is the Chinese national standard covering the reference instruments a meteorological service uses to give humidity its value — the classification of those standards and, for the chilled mirror dew point meter, the electric ventilation psychrometer, the two-pressure and two-temperature generator, the split-flow generator and the saturated salt generator alike, the general requirements, the measurement performance and the environmental adaptability that decides whether a standard holds its value outside the laboratory. First edition, under the China Meteorological Administration, with the humidity test method standard GB/T 45956-2025. In force from 1 February 2026. Issued on 1 August 2025, it has been in force since 1 February 2026.

Document preview — GB/T 45954-2025

National Standard of the People's Republic of China

ICS: 07.060
Classification: A 47

Issued by: State Administration for Market Regulation; Standardization Administration of the PRC

PrefaceIII
1 Scope1
2 Normative references1
3 Terms and Definitions1
4 ratings2
5 Technical Requirements2
5.1 Chilled Mirror Dew Point Meter2
5.1.1 General requirements2
5.1.2 Measurement performance2
5.1.3 Environmental adaptability3
5.2 Electric ventilation psychrometer3
5.2.1 General requirements3
5.2.2 Measurement performance3
5.2.3 Environmental adaptability3
5.3 Dual pressure (temperature) humidity generator4
5.3.1 General requirements4
5.3.2 Measurement performance4
5.3.3 Environmental adaptability4
5.4 Split-flow humidity generator4
5.4.1 General requirements4
5.4.2 Measurement performance4
5.4.3 Environmental adaptability5
5.5 Saturated salt humidity generator5
5.5.1 General requirements5
5.5.2 Measurement performance5
5.5.3 Environmental adaptability5

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting.

Please note that some of the contents of this document may involve patents. The issuing organization of this document does not assume the responsibility for identifying patents.

This document was proposed by the China Meteorological Administration.

This document is under the jurisdiction of the National Technical Committee for Standardization of Meteorological Instruments and Observation Methods (SAC/TC507).

This document was drafted by: China Meteorological Administration Meteorological Observation Center, Chinese People's Liberation Army 61540 Unit, Tibet Plateau Atmospheric Environment Science Research Institute, Huayun Shengda (Beijing) Meteorological Technology Co., Ltd., Xinjiang Uygur Autonomous Region Meteorological Technology and Equipment Support Center, Shandong Provincial Meteorological Meteorological Engineering Technology Center, Hunan Meteorological Technology and Equipment Center, Zhejiang Atmospheric Detection Technology Support Center, Tianjin Yunyao Aerospace Technology Co., Ltd.

Co., Ltd., Zog Microsystems (Hangzhou) Co., Ltd.

The main drafters of this document are: Li Songkui, Chen Xi, Ding Hongying, Jiang Mingbo, Li Aili, Lu Xin, Yin Xingchen, Qiu Shi, Yuan Shuai, Zhao Xu, Luo Chang, Li Fenghui and Miao Chenbiao.

General technical requirements for meteorological measurement standards - Air humidity

1 Scope

This document gives the classification of air humidity measurement standards for meteorological purposes and specifies their technical requirements.

This document applies to the design, production, testing and type evaluation of meteorological air humidity measurement standards.

2 Normative references

GB/T 37467-2019

3 Terms and Definitions

The terms and definitions defined in GB/T 37467-2019 and the following apply to this document.

3.1 Chilled mirror dew point meter

An instrument that uses isobaric adiabatic cooling to measure the dew point (frost point) temperature by measuring the condensation (sublimation) temperature of water vapor on the mirror surface.

[Source. GB/T 37467-2019, 3.1.3.26, modified]

3.2 [Source. GB/T 37467-2019, 3.1.3.18, modified]

A psychrometer with a motorized ventilation unit to control the ventilation rate.

3.3

Under certain temperature conditions, the gas is pressurized and saturated in the saturation chamber (device), and then decompressed and expanded in the test chamber.

An instrument that tests the pressure ratio of a chamber and obtains a stable airflow with different humidity levels.

3.4

Under constant pressure conditions, the gas at a certain temperature is saturated in the saturator (chamber), and then the temperature is raised in the test chamber.

An instrument that adjusts the temperature of the saturator and test chamber to obtain a stable airflow with different humidity.

3.5

An instrument that mixes dry gas and saturated wet gas in different proportions under certain temperature conditions to obtain a stable airflow with different humidity.

3.6

An instrument that uses a saturated salt solution to reproduce the relative humidity of air.

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 15 pages — is available in the English PDF.

Referenced standards

Normative references

GB/T 37467-2019Terminology for meteorological instrument

Editions of GB/T 45954

Edition	Title	Revision	Status
GB/T 45954-2025	General technical requirements for meteorological measurement standards - Air humidity	current edition	Current

This page sells the current edition, GB/T 45954-2025. Earlier editions are listed for reference only.

How to Buy GB/T 45954-2025

1Add to cart. Click the "Buy GB/T 45954-2025" button on this page. You can add more standards before checkout.
2Checkout. Enter your email and billing details. Payment is processed securely by Stripe (cards, Apple Pay, Google Pay supported).
3Instant delivery (0–9 sec). Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4Invoice included. A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.