GB/T 12474-2008Method of test for explosion limits of combustible gases in air (English PDF)

Foreword

This corresponds to the standard ISO 10156:1996 "Gases and gas mixtures cylinder valve port selecting fire potential and oxidizing ability measured Given "second edition (in English), non-equivalent, the main differences are as follows.

--- Remove the calculation method of "air of flammable gases and gas mixtures" in;

--- Delete the words "oxidation gases and gas mixtures" experiment and calculation;

--- Remove the appendix;

--- This standard can be the entire device is heated to a maximum of 50 °C test.

This standard replaces GB/T 12474-1990 "Determination of explosion limits of combustible gases in the air." This standard and GB/T 12474-the main changes compared to 1990 are as follows.

--- Increasing the "Introduction";

--- Added "normative references";

--- Increase the terms of entry;

--- Increasing the test principle;

--- Valve added other ways;

--- Increasing the explosions of judgment;

--- Standard text format press on GB/T 1.1-2000 made editorial changes.

Please note that some of the content of this standard may involve proprietary content. The standard release mechanism should not bear the identification of these patents responsibility.

The standard proposed by the People's Republic of China Ministry of Public Security.

This standard by the National Standardization Technical Committee on Fire First Technical Committee (SAC/TC113/SC1) centralized.

Introduction

Explosive limit combustible gases used in hazard classification. There are explosive process equipment allowable concentration of combustible gases, explosive Computing environment gas ventilation and heating systems, hot work safety when concentrations are determined with the explosion limit of the parameters.

The method according to this standard is not formed flame spread and ignited flammable gas-air mixture, not fully consider the mixed gas is not Explode.

Explosive limit combustible gas and air mixture to the following factors.

a) the type of combustible gas and chemical properties;

b) the purity of the combustible gas;

c) the uniformity of combustible gas and air mixture;

d) in the form of an ignition source, energy and ignition position;

e) explosive containment vessel geometry and dimensions;

f) the temperature of the combustible gas and air mixture, pressure and humidity.

Explosive limit combustible gases in air Determination

1 Scope

This standard specifies the method for determination of explosion limits of combustible gases in the air.

This standard applies to the determination of the limits of combustible gas explosion at atmospheric pressure in air.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 5907-1986 fire first part basic terms

3 Terms and Definitions

GB/T 5907-1986 and established the following terms and definitions apply to this standard.

Combustible gas and air mixture consisting of fire source that can explode lowest concentration of combustible gases.

Combustible gas and air mixture consisting of fire source that can explode the highest concentration of combustible gases.

Test Method 4