Chapter 2804 — Customs Tariff Headings
Subheadings
Products classified under Tariff item 28.04
Fuel Cell Grade Hydrogen
>- Fuel cell grade hydrogen is a high-purity elemental gas (≥99.97%) used as a fuel in proton exchange membrane (PEM) fuel cells for vehicles and stationary power systems. It is a separate chemical element of Chapter 28, meeting the criteria of Note 1(a) to Chapter 28, and is not excluded by Chapter 27 since it is not a petroleum or hydrocarbon fuel. The product is classified under tariff item 2804.10.00 as hydrogen, regardless of its end use.
2804.10.00High-Purity Hydrogen for Laboratories
>- High-purity hydrogen for laboratories is an ultra-pure elemental gas (99.999%) used as a carrier gas or fuel in analytical instruments such as gas chromatographs and spectrometers. It is a separate chemically defined element of Chapter 28, meeting the purity and form requirements of Note 1(a). The product is classifiable under tariff item 2804.10.00 as hydrogen, with no further processing or admixture.
2804.10.00Industrial Grade Hydrogen Gas
>- Industrial grade hydrogen gas is compressed elemental hydrogen used in welding, metal cutting, chemical synthesis, and other manufacturing processes. It is a separate non-metal element of Chapter 28, meeting the criteria of Note 1(a) as a chemically defined element, even if it contains minor impurities. The product is classifiable under tariff item 2804.10.00 as hydrogen, regardless of its industrial application.
2804.10.00Liquid Hydrogen for Rocket Propulsion
>- Liquid hydrogen for rocket propulsion is hydrogen in a cryogenic liquid state (-253°C), used as a fuel in aerospace applications. The physical state does not affect its classification as a separate chemical element under Chapter 28, and it meets the criteria of Note 1(a). It is classifiable under tariff item 2804.10.00 as hydrogen, with no exclusions for end use.
2804.10.00Medical Hydrogen Inhalation Gas
>- Medical hydrogen inhalation gas is pharmaceutical-grade hydrogen used in therapeutic inhalation devices, meeting USP standards. It is a chemically defined element of Chapter 28, and its medical use does not exclude it from heading 28.04, as Chapter 28 covers separate elements regardless of application. The product is classifiable under tariff item 2804.10.00 as hydrogen, provided it is not put up in measured doses for retail sale.
2804.10.00Welding Hydrogen Gas Cylinder
>- Welding hydrogen gas cylinders contain hydrogen gas for oxy-hydrogen welding torches, supplied in large cylinders. The hydrogen is a separate chemical element meeting Chapter 28 Note 1(a), and minor stabilizers or impurities are permitted under Note 1(d) if necessary for preservation or transport. It is classifiable under tariff item 2804.10.00 as hydrogen, as it is not a mixture with other gases.
2804.21.00Argon for Semiconductor Manufacturing
Hyper-pure argon (6N purity) in tonner cylinders for sputter deposition and plasma etching in wafer fabrication cleanrooms. This is elemental argon in gaseous form, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00Argon Gas for 3D Metal Printing
Pure argon gas supplied in large format cylinders for selective laser melting (SLM) in additive manufacturing, preventing oxidation during metal powder fusion. This is elemental argon in gaseous form, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00Argon Shielding Gas for Steel Fabrication
Commercially pure argon in 300 cu ft cylinders for GMAW welding in heavy steel fabrication, creating inert shield against atmospheric contamination. This is elemental argon in gaseous form, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00High Purity Argon for Laboratories
Ultra-high purity argon (99.9999%) in small lecture bottles for analytical chemistry, spectroscopy, and inert atmosphere glove boxes. This is chemically defined pure argon gas, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00Industrial Grade Argon Gas
Pure argon gas, chemically defined as a rare gas with atomic number 18, supplied in high-pressure cylinders for industrial applications. This is elemental argon in gaseous form, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00Medical Grade Argon Plasma Coagulation Gas
Sterile, ultra-pure argon gas in disposable cartridges for argon plasma coagulation (APC) devices used in endoscopy to control bleeding. This is pure argon rare gas, provided it is not pre-mixed or in a measured dose for retail sale as a medicament.
2804.21.00Spectroscopy Grade Argon
Argon gas with impurity levels below 1 ppm, packaged in 40L cylinders for inductively coupled plasma (ICP) spectroscopy elemental analysis. This is chemically defined pure argon, a rare gas of Chapter 28, and is not mixed with other substances.
2804.21.00Welding Grade Argon Cylinder
High-purity argon gas (99.999%) in 250 cubic foot steel cylinders, optimized for TIG and MIG welding to provide an inert shielding atmosphere. This is pure argon, a rare gas of Chapter 28, and is not mixed with other substances.
2804.29.00Argon-36 Isotopically Pure Gas Cylinder
Argon-36 gas with 99%+ volume isotopic purity, imported in compressed cylinders for geochronology and stable isotope studies. It is an isotopically pure rare gas.
2804.29.00Argon-38 Calibration Gas
Argon-38 calibration gas is a stable isotope of argon, a rare gas, mixed at trace levels in a 1-liter cylinder for mass spectrometry calibration. It qualifies as a separate chemical element under Chapter 28, as it is not a radioactive isotope and falls under the 'other' rare gases category.
2804.29.00Argon Gas for Welding
High-purity argon gas for welding is a rare gas in elemental form, used as an inert shielding atmosphere in MIG/TIG welding. It falls under tariff item 2804.29.00 as 'other' rare gases, distinct from hydrogen and helium.
2804.29.00Helium-3/Helium-4 Hyperpure Mixture
A hyperpure helium mixture with He-3 isotopically enriched to >99% of helium content, used in dilution refrigerators for ultra-low temperature physics. It is an isotopically pure rare gas.
2804.29.00Helium-3 Research Gas
Helium-3 research gas is an isotopically separated rare gas used in neutron detection and low-temperature physics. Although helium has a specific subheading, helium-3 is classified under 'other' rare gases because it is an isotope not covered by the standard helium subheading.
2804.29.00Helium for Airship Inflation
Aviation-grade helium for airship inflation is a rare gas in elemental form, used for lift. It falls under tariff item 2804.29.00 as 'other' rare gases, as helium is not separately classified in this subheading.
2804.29.00Helium Gas Cylinder
Compressed helium gas for balloons and industrial use is a rare gas in elemental form. It falls under tariff item 2804.29.00 as 'other' rare gases, distinct from hydrogen.
2804.29.00Helium Neon Laser Gas Mixture
Helium-neon laser gas mixture is a mixture of rare gases, with helium as the primary component. It falls under tariff item 2804.29.00 as 'other' rare gases, provided the mixture is not classified elsewhere.
2804.29.00High-Purity Helium for MRI Machines
Ultra-pure helium for MRI machines is a rare gas in elemental form, used for cooling superconducting magnets. It falls under tariff item 2804.29.00 as 'other' rare gases.
2804.29.00High-Purity Neon for Semiconductor Manufacturing
Ultra-high purity (99.999%) neon gas in specialized cylinders for plasma etching in semiconductor manufacturing. It is a chemically defined rare gas, falling under this tariff item.
2804.29.00High-Purity Xenon Bulbs Gas
High-purity xenon gas for filling automotive HID headlight bulbs is a chemically defined element under heading 28.04. Supplied pure in cylinders, it meets Chapter 28 Note 1(a) as a separate chemical element, with no added substances for specific use, and is not excluded by Chapter 28 Note 3.
2804.29.00Industrial Krypton for Lasers
Industrial krypton gas for excimer lasers in semiconductor manufacturing and medical procedures is a separate chemically defined element under heading 28.04. It is not doped for electronics (Chapter 28 Note 8) and is not a preparation, meeting Chapter 28 Note 1(a) for elemental non-metals.
2804.29.00Industrial Welding Helium Shielding Gas
Pure helium cylinders for welding shielding gas are a rare gas in elemental form. They fall under tariff item 2804.29.00 as 'other' rare gases, distinct from hydrogen.
2804.29.00Isotopically Pure Helium-3 Gas
Helium-3 gas with isotopic purity exceeding 99% by volume, used in cryogenic research and neutron detection. It is an isotopically pure rare gas.
2804.29.00Krypton-84 Isotopically Pure Gas
Krypton-84 gas isotopically pure to 99%+ by volume, applied in laser development and atomic clock calibration. It is an isotopically pure rare gas.
2804.29.00Krypton-85 Industrial Tracer
Krypton-85 industrial tracer is a low-activity radioactive isotope of krypton used for leak detection. It is classified under 'other' rare gases, but only if its radioactivity is below the threshold for heading 28.44; otherwise, it falls under radioactive isotopes.
2804.29.00Krypton Gas Cylinder
High-purity krypton gas in compressed cylinders for industrial applications such as laser technology and lighting is a rare noble gas under heading 28.04. It is a chemically defined element per Chapter 28 Note 1(a), with no added stabilizers or solvents, and is not excluded by Chapter 28 Note 3.
2804.29.00Krypton Gas Laboratory Grade
Ultra-high purity krypton gas in glass ampoules is a rare gas used for spectroscopy and research. It is a separate chemical element, not a mixture, and falls under tariff item 2804.29.00 as 'other' rare gases.
2804.29.00Leak Detection Helium Spray
A small canister of pure helium gas with a nozzle, used for ultrasonic leak detection in HVAC and automotive systems. It is classified under this tariff item as an elemental rare gas, regardless of its packaging or intended use.
2804.29.00Liquid Helium for Cryogenic Research
Helium in liquid form at -269°C, supplied in insulated dewars for cryogenic research and dilution refrigerators. The physical state does not affect classification, as it remains the elemental rare gas.
2804.29.00Liquid Neon Cryogenic Container
A dewar flask containing liquefied neon for cryogenic research and cooling applications. The liquid state does not change its classification as an elemental rare gas.
2804.29.00Medical Grade Neon Gas
Pharmaceutical-grade neon gas in a regulated cylinder for medical lasers and respiratory mixtures. It is pure neon, meeting strict purity standards for healthcare applications.
2804.29.00Neon-20 Isotopically Pure Gas
Neon-20 gas enriched to greater than 99% isotopic purity by volume, used in precision mass spectrometry and nuclear physics experiments. It is an isotopically pure rare gas.
2804.29.00Neon-20 Research Isotope
Neon-20 research isotope is a stable isotope of neon, a rare gas, enriched for nuclear physics research. It is classified under 'other' rare gases as it is not a radioactive isotope and is a separate chemical element.
2804.29.00Neon Calibration Gas Standard
A certified neon gas standard in a small cylinder for calibrating gas chromatographs and spectrometers. It is pure neon, providing a precise concentration for analytical instrumentation.
2804.29.00Neon for Neon Sign Fabrication
Industrial-grade neon gas in disposable cylinders for filling neon sign tubes. It is a chemically defined rare gas, classified under this tariff item.
2804.29.00Neon Gas Cylinder
Compressed neon gas for signage and lighting is a rare gas in elemental form. It falls under tariff item 2804.29.00 as 'other' rare gases, distinct from hydrogen and helium.
2804.29.00Neon Laser Gas Mixture Base
Pure neon gas intended for mixing into helium-neon laser gases, imported separately. It is a chemically defined rare gas, classified under this tariff item.
2804.29.00Party Balloon Helium Canister
A disposable canister containing 99.99% pure helium, designed for inflating party balloons. It is classified as an elemental rare gas, not as a preparation or mixture.
2804.29.00Radon Gas Calibration Standard
Radon-222 calibration gas is a radioactive isotope of radon, a rare gas, used in environmental monitoring. It is classified under 'other' rare gases only if its radioactivity is below the threshold; otherwise, it falls under radioactive isotopes.
2804.29.00Research-Grade Krypton
Research-grade krypton with ultra-high purity (>99.999%) for spectroscopy and particle physics experiments is a chemically defined rare gas under heading 28.04. It meets Chapter 28 Note 1(a) as a separate element, with no added substances, and is not doped for electronics per Chapter 28 Note 8.
2804.29.00Research Grade Neon Isotope
Enriched neon-20 isotope gas for nuclear physics research, classified as neon unless radioactive. Non-radioactive isotopes of rare gases fall under this tariff item.
2804.29.00Xenon-129 Isotopically Pure Gas
Xenon-129 isotopically pure gas, enriched to 99%+ isotopic purity by volume, is a separate chemically defined element of heading 28.04. It is used in NMR spectroscopy and medical imaging research, and qualifies under Chapter 28 Note 1(a) as a chemical element, with no added substances rendering it specific for a particular use.
2804.29.00Xenon-129 MRI Contrast Gas
Hyper-polarized xenon-129 gas for MRI is a rare gas isotope used in medical imaging research. It is a separate chemical element, not a mixture, and falls under tariff item 2804.29.00 as 'other' rare gases.
2804.29.00Xenon-131 Isotope Gas for MRI
Xenon-131 isotope gas, purified to 99%+ isotopic composition by volume, is a separate chemically defined element under heading 28.04. It is specialized for hyperpolarized MRI lung imaging, and its high isotopic purity aligns with Chapter 28 Note 1(a) for chemical elements, without added stabilizers or solvents.
2804.29.00Xenon Calibration Gas
Pure xenon gas cylinder for calibrating mass spectrometers and gas chromatographs is a chemically defined rare gas under heading 28.04. It is a separate element per Chapter 28 Note 1(a), with no added stabilizers or solvents, and is not a mixture or organic compound, thus within Chapter 28 scope.
2804.29.00Xenon Gas for Lighting
Purified xenon gas for lighting is a rare gas in elemental form, used in xenon arc lamps. It falls under tariff item 2804.29.00 as 'other' rare gases, distinct from helium and neon.
2804.30.00Bulk Liquid Nitrogen ISO Tank
Bulk liquid nitrogen transported in ISO cryogenic tanks for industrial supply chains. It is elemental nitrogen in liquid form, a non-metal of Chapter 28, and is not excluded by any Chapter 28 note.
2804.30.00Cryogenic Nitrogen for MRI Cooling
Liquid nitrogen used for cooling superconducting magnets in MRI machines. It is elemental nitrogen in liquid form, classifiable under Chapter 28 as a non-metal, and not excluded by the chapter notes.
2804.30.00Food Grade Nitrogen Gas
Nitrogen gas meeting food-grade purity standards for Modified Atmosphere Packaging (MAP). It is elemental nitrogen, a non-metal, and food use does not exclude it from Chapter 28.
2804.30.00High Purity Nitrogen 99.999% UHP
Ultra-high purity nitrogen gas at 99.999% N2, supplied in specialty cylinders for laboratory and semiconductor cleanrooms. It is a separate chemical element, classifiable under Chapter 28, and not excluded by the notes.
2804.30.00Industrial Grade Nitrogen Gas
Pure nitrogen gas compressed in high-pressure steel cylinders for industrial applications such as blanketing and purging. It is chemically pure nitrogen, a non-metal, and falls under Chapter 28.
2804.30.00Laboratory Nitrogen Zero Grade
Zero-grade nitrogen with ultra-low hydrocarbon impurities for analytical instruments like GC-MS. It is high-purity elemental nitrogen, classifiable under Chapter 28, and lab use does not exclude it.
2804.30.00Liquid Nitrogen Cryogenic
Liquefied nitrogen (LIN) at -196°C in Dewar flasks or bulk tanks for cryopreservation and cooling. It is elemental nitrogen in liquid form, a non-metal, and not excluded by Chapter 28.
2804.30.00Medical Grade Nitrogen NF
National Formulary (NF) nitrogen gas for pharmaceutical and medical applications like cryogenic therapy. It is chemically defined elemental nitrogen in Chapter 28, and medical use does not exclude it.
2804.30.00Nitrogen for Tire Inflation
High-purity nitrogen for inflating vehicle tires, reducing oxidation in racing and fleet applications. It is pure non-metal nitrogen gas, classifiable under Chapter 28.