G21K HANDLING OF PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
Introduced: September 1968
Last revised: July 1974
Classification Context
- Section:
- PHYSICS
- Class:
- NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- Subclass:
- HANDLING OF PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
Description
G21K covers apparatus and methods for handling particles and ionizing radiation that do not fall within more specialized nuclear physics or engineering classes, including irradiation devices and microscopy systems using gamma rays or X-rays. This subclass encompasses equipment for directing, controlling, and applying particle beams and radiation sources in industrial, medical, and research applications, as well as microscopes that utilize high-energy photons for imaging. Typical technologies include radiation shielding systems, beam transport apparatus, irradiation chambers, and gamma/X-ray microscopy instruments. Excluded from this class are nuclear reactors (G21B), nuclear fuel processing (G21C), and nuclear power plant safety systems (G21D), which are covered by more specific nuclear engineering divisions.
Filing statistics
IPC subclass G21K recorded 11,603 patent applications worldwide between 2013 and 2023. Annual filings declined from 1,350 in 2013 to 867 in 2023 (-36%). The most active applicants in class G21 are CHINA GENERAL NUCLEAR POWER CORPORATION (2,364 applications), CGN POWER COMPANY (1,899 applications) and CHINA NUCLEAR POWER ENGINEERING COMPANY (1,870 applications).
Source: EPO PATSTAT, worldwide filings
In class comparison
G21K ranks 3rd of 8 subclasses with filings in G21, with 11,603 applications between 2013 and 2023, 14.4% of the class. Annual filings declined 36% from 2013 to 2023, below the class as a whole (+4%).
| Rank | Subclass | Title | Applications | Share |
|---|---|---|---|---|
| 1 | G21C, Nuclear Reactors | Nuclear Reactors | 29,798 | 37.0% |
| 2 | G21F, Protection Against X-Radiation, Gamma Radiation, Corpuscular Radiation or Particle Bombardment; Treating Radioactively Contaminated Material; Decontamination Arrangements Therefor | Protection Against X-Radiation, Gamma Radiation, Corpuscular Radiation or Particle Bombardment; Treating Radioactively Contaminated Material; Decontamination Arrangements Therefor | 22,783 | 28.3% |
| 3 | G21K | Handling of Particles or Ionising Radiation Not Otherwise Provided for; Irradiation Devices; Gamma Ray or X-Ray Microscopes | 11,603 | 14.4% |
| 4 | G21D, Nuclear Power Plant | Nuclear Power Plant | 7,179 | 8.9% |
| 5 | G21G, Conversion of Chemical Elements; Radioactive Sources | Conversion of Chemical Elements; Radioactive Sources | 4,076 | 5.1% |
| 6 | G21B, Fusion Reactors | Fusion Reactors | 3,917 | 4.9% |
| 7 | G21H, Obtaining Energy From Radioactive Sources; Applications of Radiation From Radioactive Sources, Not Otherwise Provided for; Utilising Cosmic Radiation | Obtaining Energy From Radioactive Sources; Applications of Radiation From Radioactive Sources, Not Otherwise Provided for; Utilising Cosmic Radiation | 1,227 | 1.5% |
| 8 | G21J, Nuclear Explosives; Applications Thereof | Nuclear Explosives; Applications Thereof | 58 | 0.1% |
Source: EPO PATSTAT, worldwide filings
Additional Content
Ionising radiation ‘Ionising radiation’ consists of particles or electromagnetic waves that are sufficiently energetic to detach electrons from atoms or molecules, thus ionising them. Particle particles ‘Particle’ means a molecular, atomic or sub-atomic particle
Related Keywords
5 direct subcodes
Child Classifications
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- G21K 1/00 Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
- G21K 3/00 Ionising radiation filters, e.g. X-ray filters
- G21K 4/00 Conversion screens for the conversion of the spatial distribution of particles or ionising radiation into visible images, e.g. fluoroscopic screens
- G21K 5/00 Irradiation devices
- G21K 7/00 Gamma ray or X-ray microscopes
Top Applicants
Top 10 applicants by patent filingsfor class G21, 2013–2023, worldwide · Source: EPO PATSTAT
- CHINA GENERAL NUCLEAR POWER CORPORATION 2,364
- CGN POWER COMPANY 1,899
- CHINA NUCLEAR POWER ENGINEERING COMPANY 1,870
- NUCLEAR POWER INSTITUTE OF CHINA 1,517
- KOREA ATOMIC ENERGY RESEARCH INSTITUTE KR 1,367
- WESTINGHOUSE ELECTRIC CORPORATION US 1,295
- KOREA HYDRO & NUCLEAR POWER COMPANY KR 1,196
- CHINESE ACADEMY OF SCIENCES 1,044
- CHINA INSTITUTE OF ATOMIC ENERGY 1,011
- HITACHI-GE NUCLEAR ENERGY 955