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CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES (applications of radiation in general G21H 5/00; handling particles, e.g. neutrons, or electromagnetic radiation not otherwise provided for G21K)
Definition statement
This subclass/group covers:

Methods and apparatus for the conversion of chemical elements, e.g. isotope production or transmutation where a change of atomic number takes place either externally induced or by radioactive decay.

Radioactive sources (solid, liquid or gas).

References relevant to classification in this subclass
This subclass/group does not cover:
Conversion of nuclear fuel
Adaptations of reactors to facilitate experimentation or irradiation. Examples of such adaptations include modification of the reactor core to enable exposure of samples for investigative purposes
Applications of radiation in general
Handling particles.
Irradiation devices. These typically include arrangements to deliberately subject bodies or materials to ionising radiation in order to take advantage of known effects of the radiation thereon
X-ray tubes

Examples of places where the subject matter of this subclass is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Radiopharmaceuticals
Applying radioactive material to the body
A61M36/00
Radiation therapy using radioactive sources
Detection by neutron activation
Conversion of chemical elements by thermonuclear reactions in fusion reactors
Nuclear reactors
Application of radiation from radioactive sources
Informative references
Attention is drawn to the following places, which may be of interest for search:
Preparations containing radioactive substances for use in therapy or testing in vivo
Separation of different isotopes of the same element
Handling particles or electro​magnetic radiation not otherwise provided for
Producing neutrons or other subatomic particles, X- or gamma rays:
In fusion reactors
In nuclear reactors
By cosmic radiation
In accelerators
X-ray tubes
Gamma masers
Special rules of classification within this subclass

Indexing Codes are only used for G21G 1/00, G21G 1/0005 and G21G 1/001 for indicating supplementary information. In all other cases multiple ECLA classes are assigned.

Arrangements for converting chemical elements by electromagnetic radiation, corpuscular radiation or particle bombardment, e.g. producing radioactive isotopes (separation of different isotopes of the same element B01D 59/00)
Definition statement
This subclass/group covers:
  • Apparatus and methods for transmutation and isotope production.
  • Conversion isotope generators methods of isotope recovery from targets.
  • Arrangements inside nuclear power reactors
  • Arrangements outside nuclear power reactors, e.g. conversion by bombardment with electrically charged particles or neutrons.

Further information:

The indexing scheme under G21G 1/00 covers: isotope delivery systems; methods for recovering isotopes. Individual subgroups are used to identify particular isotopes recovered from irradiated targets.

References relevant to classification in this group
This subclass/group does not cover:
Separation of different isotopes of the same element (enrichment)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Applications of electromagnetic radiation
Irradiation devices
Targets for nuclear reactions
Special rules of classification within this group

Referring to reactors is intended for power reactors which primarily supply electricity to the power grid; otherwise G21G 1/06 should be used.

May be assigned to inventions in other classes where isotope conversion, recovery or delivery takes place but is not the main focus.

G21G 2001/0015 through G21G 2001/0094 should only be used these particular isotopes are recovered. For more general methods, useful for large groups/lists of isotopes, G21G 1/001 should be given.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Transmutation
Conversion of nuclear waste to less problematic isotopes.
Generator
Shielded delivery system containing a mother isotope which can be eluted or "milked" to deliver an isotope product, which usually has a short half-life, e.g. Technetium-99m.
Synonyms and Keywords

In patent documents the following abbreviations are often used:

Isotope delivery system
"Generator", "cow", ion exchange column.
Radioactive sources (producing neutrons or other subatomic particles, X- or gamma rays, in fusion reactors G21B, in nuclear reactors G21C, by cosmic radiation G21H 7/00, in accelerators H05H; X-ray tubes H01J 35/00; gamma masers H01S 4/00)
Definition statement
This subclass/group covers:
  • Sources of ionising radiation which emit according to radioactive decay.
  • Neutron sources or other sources used generally or for medical applications.
References relevant to classification in this group
This subclass/group does not cover:
Producing neutrons or other subatomic particles, X- or gamma rays in fusion reactors
Producing neutrons or other subatomic particles, X- or gamma rays in nuclear reactors
Producing neutrons or other subatomic particles, X- or gamma rays by cosmic radiation
Informative references
Attention is drawn to the following places, which may be of interest for search:
Filling medical containers
Radioactive dressings
A61M36/14
Radiation therapy
Filling medical containers and related operations
B65B3/00B3
Producing neutrons or other subatomic particles, X- or gamma rays by using sources as tracers
X-ray tubes
Gamma masers
Plasma eUV sources
Production of accelerated electrically-charged particles or of neutrons, e.g. using accelerators
Alleged conversion of chemical elements by chemical reaction
Definition statement
This subclass/group covers:

Alchemy, e.g. alleged induction of radioactive decay by chemical means.

References relevant to classification in this group
This subclass/group does not cover:
Cold fusion
Special rules of classification within this group

This main group should only be given when a change of atomic number by chemical means is explicitly disclosed. This may also include alleged induction of radioactive decay by chemical means.

Conversion of chemical elements not provided for in other groups of this subclass
Definition statement
This subclass/group covers:

Miscellaneous apparatus or methods for converting elements or generating isotopes not induced by electromagnetic radiation, corpuscular radiation or particle bombardment.

Such methods which contradict standard physics.

Special rules of classification within this group

This main group should only be given if no other group in this subclass can be assigned.

This page is owned by Office of Patent Classification.
Last Modified: 10/11/2013