The particularity of the standard gas has special requirements for sampling. Many users have large data deviations due to non-standard sampling. Here are several aspects that should be paid attention to in sample sampling:

1. The choice of sampling pipeline. Because the hose is very convenient to use, many traditional sampling pipelines use this type. However, the hose has strong adsorption to most organic gases and sulfur-containing gases, and its permeability is also very strong, so it is not advisable to use various types of hoses for sampling. It is recommended to use copper tubes, stainless steel tubes, and PTFE tubes according to different gas properties.

2. The replacement of sample gas. Since the standard gas must pass through the pressure reducer and pipeline before sampling, the pressure reducer and pipeline must be fully replaced for accurate sampling. The cylinder valve is opened and closed repeatedly for more than 3 times, each time the gas in the pressure reducer is exhausted, and then the system is purged to correctly sample.

3. The airtightness of the sampling pipeline. The leakage of the sampling pipeline has a great influence on the accuracy of the sample data, especially for low concentration of oxygen.

4. It is not advisable to try to take the standard gas from the standard gas cylinder into a sampling bag or other container, and then sample and analyze it from the container, which causes secondary pollution.