GB/T 40531.1-2021

Ships and marine technology—Specifications for gas detectors intended for use on board ships—Part 1:Portable gas detectors for atmosphere testing of enclosed spaces (English Version)

Standard No.

GB/T 40531.1-2021

Language

Chinese, Available in English version

Release Date

2021

Published By

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China

Latest

GB/T 40531.1-2021

Scope

This document specifies the performance, measurement gas, sensitivity, result display, alarm level, impact resistance, temperature and humidity protection and measurement requirements of portable gas detectors used before entering enclosed spaces on board ships. This document can be used for the detection of portable gas detectors to prove whether they comply with the requirements of SOLAS Convention XI1/7 "Gas Detectors in Enclosed Spaces", and can also be used to determine whether portable gas detectors on the market comply with the requirements of the SOLAS Convention. Note 1: From July 1, 2016, SOLAS Convention XI1/7 stipulates portable gas testing equipment and on-board equipment. The SOLAS Convention requires that the portable gas testing equipment on board the ship can at least test the concentration of oxygen, combustible gas or vapor, hydrogen sulfide and carbon monoxide before entering the enclosed space. In order to measure the concentration of combustible gas or vapor, the combustible gas described in this document is a mixture of methane or propane and butane, and it is required to clearly mark the type of combustible gas on the portable gas detector. Unmarked combustible gases cannot be detected and measured by portable gas detectors. Note 2: Portable gas detectors can use isobutane as a calibration gas when measuring propane and butane gases. This document does not apply to the toxicity test of combustible gas.

Introduction

Interpretation of the core content of the standard

This document is equivalent to the ISO198911:2017 international standard, which specifies the technical requirements for the application of portable gas detectors in enclosed spaces on ships. It is mainly used to prove whether the equipment complies with the requirements of Article XI1/7 of the SOLAS Convention.

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Key Technical Requirements

Detection Items	Accuracy Requirements	Alarm Threshold	Test Standards
Oxygen	±1%(0-40℃)	Default 18%	IEC600792-91
Combustible Gas	LFL Percentage	Default 30%LFL	IEC600792-92
Hydrogen Sulfide	ppm Level	Default is 10ppm	IMO Res.A.1050(27)

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Key points for implementation

Equipment selection recommendations

Note when selecting a portable gas detector:
1. The type of gas that can be measured (methane/propane/butane) must be clearly marked
2. It must have an IP65 protection grade and explosion-proof certification
3. The battery life must be ≥10 hours and it must have a battery level display

Maintenance and calibration requirements

According to clause 4.4.2 of the standard:
- A regular calibration system must be established
- Functional verification should be performed before each use
- Complete calibration records must be kept

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Background of Standard Evolution

This standard is formulated based on the revised requirements of the 2016 SOLAS Convention, and for the first time, enclosed space gas detection equipment is included in the mandatory specifications. Major changes compared with the old version:
1. Added hydrogen sulfide/carbon monoxide detection requirements
2. Clarified the management specifications for external replaceable modules
3. Detailed alarm threshold setting rules

GB/T 40531.1-2021 Referenced Document

• IEC 60079-0 Interpretation Sheet 2 - Explosive atmospheres - Part 0: Equipment - General requirements
• IEC 60533 Electrical and electronic installations in ships — Electromagnetic compatibility (EMC) — Ships with a metallic hull

GB/T 40531.1-2021 history

• 2021 GB/T 40531.1-2021 Ships and marine technology—Specifications for gas detectors intended for use on board ships—Part 1:Portable gas detectors for atmosphere testing of enclosed spaces