Product classification
HS code for Gas generators: 8405.10
Generators, producer gas, water gas, acetylene gas and similar water process gas generators, with or without their purifiers.
Classification of gas generators under HS 8405.10
HS code 8405.10 is specifically designated for producer gas or water gas generators, with or without their purifiers, as well as acetylene gas generators and similar water process gas generators. The classification is determined by the functional nature of the machinery, which must involve a chemical or thermal process to generate gas from solid fuels like coal, coke, or charcoal, or through the controlled reaction of water with certain chemicals such as calcium carbide for acetylene production. This code is specific to the production of the gas itself as a raw material or fuel source, rather than the utilization of that gas for mechanical power. The inclusion of purifiers is permitted under this heading provided they are imported or exported as part of the generator system; standalone purifiers might be classified elsewhere depending on their specific technology. These generators are often used in industrial settings where a steady supply of specific gases is required for chemical synthesis or metalworking. The classification also covers water gas generators which produce a mixture of hydrogen and carbon monoxide by passing steam over incandescent fuel.
- Covers
- Producer gas generators using coal or wood
- Water gas generators
- Acetylene gas generators (wet and dry types)
- Blue water gas generators
- Purifiers specifically designed for and presented with the above generators
- Gas-generating units for laboratory use operating on these principles
- Also under 8405.10
- Messer Group acetylene generators
- Air Products syngas generators
- Linde gasification plants
- Praxair industrial gas generators
Codes often confused with 8405.10
Common mistake. A frequent error is classifying these units under HS code 8502, which covers electric generating sets. The distinction lies in the output: 8405 produces gas, while 8502 produces electricity. Another common confusion occurs with HS code 8411, which covers gas turbines; while turbines use gas, they do not generate the gas itself. Additionally, ozone generators are excluded from this heading and are typically classified under HS code 8543, as they operate on an electrical discharge principle rather than a water or thermal process.
Top exporters and importers of HS 840510 (the code used for gas generators), 2025
In 2025, the largest exporter of HS 840510 (the code used for gas generators) in UN Comtrade data was China, with 12% of world exports; the largest importer in UN Comtrade data was South Korea, with 12% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 840510, not only gas generators.
Top exporters 2025 · share of world exports
- 1 China $79M 12% of world exports
- 2 Belgium $73M 11% of world exports
- 3 Italy $53M 8.4% of world exports
World total: $637M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 South Korea $83M 12% of world imports
- 2 Belgium $53M 7.3% of world imports
- 3 Ireland $41M 5.7% of world imports
World total: $720M Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for gas generators
Brazil classifies gas generators under NCM 8405.10.00: HS 8405.10 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about gas generators
What is the HS code for Gas generators?
The HS code for Gas generators is 840510 (Generators; producer gas, water gas, acetylene gas and similar water process gas generators, with or without their purifiers). The correct HS code for gas generators, including producer gas and acetylene gas generators, is 8405.10.
How do I classify Gas generators for customs?
Gas generators is classified under HS code 840510 — Generators; producer gas, water gas, acetylene gas and similar water process gas generators, with or without their purifiers. This is a 6-digit subheading level code.
Can this code include purifiers?
Yes, gas purifiers are classified under 8405.10 if they are presented with the gas generator they are intended for. Standalone filtering or purifying machinery is usually classified under HS code 8421.
Which countries are the top exporters of gas generators (HS 840510)?
In 2025, the top exporters of HS 840510 (the code used for gas generators) in UN Comtrade data were China ($79M, 12% of world exports), Belgium ($73M) and Italy ($53M). World exports came to about $637M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of gas generators (HS 840510)?
In 2025, the top importers of HS 840510 (the code used for gas generators) in UN Comtrade data were South Korea ($83M, 12% of world imports), Belgium ($53M) and Ireland ($41M). World imports came to about $720M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Is the HS code for Gas generators the same in all countries?
The base HS code 840510 for Gas generators is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for gas generators in Brazil?
In Brazil, gas generators (HS 840510) is classified under NCM 8405.10.00.