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ORT's High Concentration Sulfur Dioxide Test Standard Was Issued By The State Administration For Market Regulation

The High Concentration Sulfur Dioxide Test Standard drafted by ORT was authoritatively issued by the State Administration for Market Regulation

Ⅰ. Basic situation of high concentration sulfur dioxide test standard

The name of the standard:

Environmental Test. Part 2: Test Method. Test Kca: High concentration sulfur dioxide test

Standard No.: GB/T 2423.33-2021

This standard replaces GB/T 2423.33-2005《Environmental test of electrical and electronic products Part 2: Test method test Kca: High concentration sulfur dioxide test》

This standard will be released on May 21, 2021, and will be implemented on December 1, 2021.

This standard is reported under TC8 (National Standardization Technical Committee for Environmental Conditions and Environmental Tests of Electrical and Electronic Products), and TC8/SC2 (Climate Environmental Testing Branch of National Standardization Technical Committee for Environmental Conditions and Environmental Tests of Electrical and Electronic Products) is implemented. The competent authority is the national standardization Management Committee.

The range of standards:

This standard specifies the general conditions and methods for testing samples in the alternating climate of condensed water containing high concentrations of sulfur dioxide, especially for the sulfur dioxide concentration not included in GB/T 9789-2008, so that it can obtain comparable test results when tested in different laboratories.

This standard is applicable to determine the suitability of products and materials used in chemically corrosive environments.

The content of this standard does not include sample shape, sample preparation, and analysis and evaluation of test results. Regarding these provisions, you can consult the relevant standards or negotiate according to the specific situation.

This test cannot be used directly for comparison of corrosion resistance unless the application environment of the anti-corrosion system is similar. Because the corrosion test conditions are very different from the actual application conditions, the corrosion process and the corrosion mechanism are different.

Test Conditions:

The sample should be placed in the test chamber in the state of being Unpackaged, Non-Operation, "Ready to use", or in the state specified by the relevant specifications.

Test conditions are listed in Table 1. The test conditions listed in Table 1 are partly different from those in GB/T 9789-2008. However, when testing, it is still necessary to consider 6.1, 6.2, and 6.4 of GB/T 9789-2008.

Note: Most of the sulfur dioxide gas introduced at the beginning of the first test phase quickly dissolves into the water at the bottom of the test chamber. Therefore, the effective concentration of sulfur dioxide in the gas space is approximately one-seventh of the theoretical concentration. During the first experimental phase, this starting concentration did not remain constant, but first decreased sharply and then slowly.

At the beginning of the second stage of the test, the heating should be stopped, and the test chamber should be opened or ventilated. After about 1.5H, the test conditions given in Table 1 should be met.

Table 1 Test conditions

Test Item

Test Kca 1

Test Kca 2

Test conditions

The theoretical concentration   of  SO2(volume fraction) at   the beginning of each test period

0.33 %a

067 %b

Test period

The first test phase

8h, including heating.

The second test phase

16h, including cooling (open the   test chamber or ventilate)

Total time


Exposure conditions in the test   chamber

The first test phase




About 100% (condensation water is   generated on the sample)

The second test phase





The amount of water at the bottom of   the test chamber (volume fraction)


a. In a test chamber with a volume of   300L, the theoretical concentration of sulfur dioxide is equivalent to the amount of sulfur dioxide in each test cycle, 1.0L, and 2.0L respectively.

b. When the volume of the test chamber is 300L, this concentration is equivalent to 2L of water.

Test Time:

Unless otherwise specified, the test cycle shall be selected first from the following cycles: 1, 2, 5, 10, 15, or 20 cycles, one cycle is 24h. If corrosion damage has occurred during the test to an unacceptable level, that is, the appearance or function of the sample has been damaged, the test can be terminated.

Usually, the water and sulfur dioxide gas in the test system should be replaced at the end of each cycle, and the replacement should not interfere with the sample.

Intermediate detection

Relevant specifications may stipulate that electrical and/or other performance tests should be performed on the samples in the test chamber within 3 hours before the end of each cycle during the test period. After the performance test, it is allowed to open the test chamber to take and place the sample, and the opening time should be as short as possible, and it should be completed within 0.5h before the temp. rise.

Ⅱ. Failure mechanism of high concentration sulfur dioxide test

1. A strong reducing agent, which has a strong corrosive ability to general non-metallic surface coatings and non-metallic materials; the corrosion to the surface of metal materials is due to the chloride ion penetrating the oxide layer and protective layer of the metal and the interior caused by a chemical reaction of metals.

2. Form strong acid, which has a strong corrosive ability to general non-metal surface coating and non-metal materials.

3. The generated sulfurous acid and sulfuric acid directly destroy the oxide film on the surface of metal products, causing various corrosion effects such as electrochemical corrosion.

Ⅲ. High concentration sulfur dioxide test capability of ORT

The device name/model

Technical specification

Salt Spray And Corrosion Cycling Test Chamber

Salt spray and corrosion cycling test chamber

Manufacturer: WEISS, Germany

1)Test volume: 450 Itr

2)Salt spray temp. range:+25℃~+50℃

3)Condensation temp.range:+25~+45℃

4)Temp. fluctuation: ≤±1℃

5)Temp. uniformity: ≤±2℃

6)Temp. deviation: ≤±2℃

7)Sedimentation of salt fog:(1~2)ml/80cm2.h

8)Function: salt mist test, salt spray and   SO2 cyclic test, SO2 condensation test.

9)Equipped with SOflowmeter

Ⅳ. The units involved in drafting high concentration sulfur dioxide test standards

High Concentration Sulfur Dioxide Test Standard

Ⅴ. ORT participated in the drafting of the published high concentration sulfur dioxide test standards

1. GB/T 35774-2017《运输包装件性能测试规范》

GB/T 35774-2017《Standard practice for performance testing of shipping containers》

2. GB/T 4857.1-2019《包装 运输包装件基本试验 第一部分:试验时各部位的标示方法》

GB/T 4857.1-2019《Packaging. Basic tests for transport packages. Part one: Identification of parts when testing》

3. GB/T 4798.1-2019《环境条件分类 环境参数组分类及其严酷程度分级 第1部分:贮存》

GB/T 4798.1-2019 《Classification of environmental conditions. Classification of groups of environmental parameters and their severities. Part one: Storage》

4. GB/T 2421-2020《环境试验 概述和指南》

GB/T 2421-2020《Environmental testing. General and guidance》

5. GB/T 2423.27-2020《环境试验 第2部分:试验方法 试验方法和导则:温度/低气压或温度/湿度/低气压综合试验》

GB/T 2423.27-2020《Environmental testing. Part two: Test methods.Test method and guidance: Combined temp. or temp. and humidity with low air pressure tests》

6. GB/T 2423.51-2020《环境试验 第2部分:试验方法 试验Ke:流动混合气体腐蚀试验》

GB/T 2423.51-2020《Environmental testing. Part two: Test methods. Test Ke: Flowing mixed gas corrosion test》

7. GB/T 32065.8-2020 《海洋仪器环境试验方法 第8部分:温度变化试验》

GB/T 32065.8-2020《Environmental test methods for oceanographic instruments. Part 8: Change of temp. test》

8. GB/T 32065.10-2020《海洋仪器环境试验方法 第10部分:盐雾试验》

GB/T 32065.10-2020《Environmental test methods for oceanographic instruments. Part 10: Salt fog test》

9. GB/T 4797.9-2021《环境条件分类 自然环境条件 贮存、运输和使用过程中测得的冲击和振动数据》

GB/T 4797.9-2021《Classification of environmental conditions. Natural environmental conditions. Shock and vibration data measured during storage, transportation and use》

10. GB/T 2423.33-2021《环境试验 第2部分:试验方法 试验Kca:高浓度二氧化硫试验》

GB/T 2423.33-2021《Environmental testing. Part 2: Test Method. Test Kca: High concentration sulfur dioxide》

11. GB/T 2423.18-2021《环境试验 第2部分:试验方法 试验Kb:盐雾、交变(氯化钠溶液)》

GB/T 2423.18-2021 《Environmental testing. Part 2: Test methods. Test Kb: Salt mist, cyclic(sodium chloride solution)》

12. NB/T 10279-2019《输变电设备 湿热环境条件》

NB/T 10279-2019《Heat and hot environmental conditions for power transmission and transformation equipment》

13. NB/T 10280-2019《电网用状态监测装置 湿热环境条件与技术要求》

NB/T 10280-2019《Condition monitoring device for power grid, Humid and hot environmental conditions and technical requirements》

14. YZ/T 0174-2020《冷链寄递保温箱技术要求》

YZ/T 0174-2020《Technical requirements for cold chain delivery incubator》

15. T/CPF 0012-2020 《快递小型运输包装件试验导则》

T/CPF 0012-2020《Test guidelines for express small transport packages》

16. T/CPF 0011-2020《电商物流大家电运输包装件试验导则》

T/CPF 0011-2020《E-commerce logistics test guidelines for major appliances transport packages》

High Concentration Sulfur Dioxide Test Standard