Product classification
HS code for Thyratron: 8540.89
Valves and tubes, n.e.c. in heading no. 8540.
Classification of thyratron under HS 8540.89
A thyratron is classified under HS code 854089. This classification falls within Chapter 85, which encompasses electrical machinery and equipment. Heading 8540 is dedicated to thermionic, cold cathode, or photo-cathode valves and tubes, such as vacuum tubes, vapor-filled tubes, and cathode-ray tubes. A thyratron is a type of gas-filled hot-cathode tube that acts as a high-power electrical switch and controlled rectifier. Because it is a specialized valve that does not fit into the more specific subheadings like television picture tubes (854011) or magnetrons (854071), it is categorized under the residual subheading 854089, which covers "other" valves and tubes. The classification is based on the physical construction of the device as a vacuum or gas-filled tube rather than a solid-state semiconductor.
- Covers
- Hydrogen thyratrons
- Mercury-vapor thyratrons
- Shield-grid thyratrons
- Gas-filled triode tubes
- High-voltage switching tubes
- Industrial rectifier tubes (non-solid state)
- Also under 8540.89
- Hamamatsu R647P Photomultiplier Tube
- Eimac 3CX1500A7 Power Triode
- Siemens RQR 12/20 Thyratron
- L3Harris TWTs (specialized)
- Philips X-ray tubes (industrial)
Codes often confused with 8540.89
Common mistake. The most frequent misclassification for a thyratron is HS code 854130, which covers thyristors (SCRs). While thyristors perform a similar electronic switching function, they are solid-state semiconductor devices. Thyratrons, by contrast, are vacuum/gas tubes and must remain in 8540. Another error is classification under 8535 or 8536 as general electrical switches; however, because the thyratron is an electronic valve, the specific heading for tubes (8540) takes precedence over general switching apparatus.
Top exporters and importers of HS 854089 (the code used for thyratron), 2025
In 2025, the largest exporter of HS 854089 (the code used for thyratron) in UN Comtrade data was the United States, with 37% of world exports; the largest importer in UN Comtrade data was China, with 15% 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 854089, not only thyratron.
Top exporters 2025 · share of world exports
- 1 United States $95M 37% of world exports
- 2 United Kingdom $34M 13% of world exports
- 3 China $29M 12% of world exports
World total: $255M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 China $45M 15% of world imports
- 2 United States $40M 13% of world imports
- 3 Philippines $31M 10% of world imports
World total: $302M 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 codes for thyratron
Brazil splits HS 8540.89 into 2 NCM codes. Pick the one that matches your product:
- 8540.89.10Transmitter power valves
- 8540.89.90Other electronic valves and tubes
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about thyratron
What is the HS code for Thyratron?
The HS code for Thyratron is 854089 (Valves and tubes; n.e.c. in heading no. 8540).
How do I classify Thyratron for customs?
Thyratron is classified under HS code 854089 — Valves and tubes; n.e.c. in heading no. 8540. This is a 6-digit subheading level code.
What is the HS code for a thyratron tube?
The HS code for a thyratron tube is 854089.
How do I distinguish a thyratron from a thyristor for HS classification?
A thyratron is a glass or ceramic tube containing gas or a vacuum (8540), whereas a thyristor is a solid-state silicon-based component (8541).
Which countries are the top exporters of thyratron (HS 854089)?
In 2025, the top exporters of HS 854089 (the code used for thyratron) in UN Comtrade data were the United States ($95M, 37% of world exports), the United Kingdom ($34M) and China ($29M). World exports came to about $255M, 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 thyratron (HS 854089)?
In 2025, the top importers of HS 854089 (the code used for thyratron) in UN Comtrade data were China ($45M, 15% of world imports), the United States ($40M) and the Philippines ($31M). World imports came to about $302M, 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 Thyratron the same in all countries?
The base HS code 854089 for Thyratron 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 thyratron in Brazil?
Brazil splits HS 854089 into 2 NCM codes, so the right one for thyratron depends on the product's details: 8540.89.10 (Transmitter power valves), 8540.89.90 (Other electronic valves and tubes).