These Notes cover the basic principles and general instructions for use of section H. Section H covers: basic electric elements, which cover all electric units and the general mechanical structure ofapparatus and circuits, including the assembly of various basic elements into what are called printed circuits and also cover to a certain extent the manufacture of these elements (when not covered elsewhere); generation of electricity, which covers the generation, conversion and distribution of electricity together with the controlling of the corresponding gear; applied electricity, which covers: general utilisation techniques, viz. those of electric heating and electric lighting circuits; some special utilisation techniques, either electric or electronic in the strict sense, which are not covered by other sections of the Classification, including: electric light sources, including lasers; electric X-ray technique; electric plasma technique and the generation and acceleration of electrically charged particles or neutrons; basic electronic circuits and their control; radio or electric communication technique; the use of a specifiedmaterial for the manufacture of the article or element described. In this connection, paragraphs88 to90 of the Guide should be referred to. In this section, the following general rules apply: Subject to the exceptions stated in I(c), above, any electricaspect or part peculiar to a particular operation, process,apparatus, object or article, classified in one of the sections of the Classification other than section H, is always classified in the subclass for that operation, process,apparatus, object or article. Where common characteristics concerning technical subjects of similar nature have been brought out at class level, the electricaspect or part is classified, in conjunction with the operation, process,apparatus, object or article, in a subclass which covers entirely the general electrical applications for the technical subject in question; The electrical applications referred to under (a), above, either general or particular, include: the therapeutic processes andapparatus, in class; the electric processes andapparatus used in various laboratory or industrial operations, in classes and and in subclass ; the electricity supply, electric propulsion and electric lighting of vehicles in general and of particular vehicles, in the subsection "Transporting" of section B; the electric ignition systems of internal-combustionengines, in subclass, and of combustionapparatus in general, in subclass; the whole electrical part of section G, i.e. measuring devices includingapparatus for measuring electric variables, checking, signalling and calculating. Electricity in that section is generally dealt with as a means and not as an end in itself; All electrical applications, both general and particular, presuppose that the "basic electricity"aspect appears in section H (see I(a) above) as regards the electric "basic elements" which they comprise. This rule is also valid for applied electricity, referred to in I(c), above, which appears in section H itself. In this section, the following special cases occur: Among the general applications covered by sections other than section H, it is worth noting that electric heating in general is covered by subclasses or or class , and that electric lighting in general is partly covered by class , since in section H (see I(c), above) there are places in which cover the same technical subjects; In the two cases referred to under (a), above, the subclasses of section F, which deal with the respective subjects, essentially cover in the first place the whole mechanicalaspect of theapparatus or devices, whereas the electricalaspect, as such, is covered by subclass; In the case of lighting, this mechanicalaspect should be taken to cover thematerialarrangement of the various electric elements, i.e., their geometrical or physical position in relation to one another; thisaspect is covered by subclass, the elements themselves and the primary circuits remaining in section H. The same applies to electric light sources, when combined with light sources of a different kind. These are covered by subclass , whereas the physical arrangement which their combination constitutes is covered by the various subclasses of class ; As regards heating, not only the electric elements and circuitry designs, as such, are covered by subclass , but also the electricaspects of their arrangement, where these concern cases of general application; electric furnaces being considered as such. The physical disposition of the electric elements in furnaces is covered by section F. If a comparison is made with electric welding circuits, which are covered by subclass in connection with welding, it can be seen that electric heating is not covered by the general rule stated in II, above. Processes involving only a single technical art, e.g. drying, coating, for which provision exists elsewhere are classified in the relevant class for that art. Attention is drawn to the Notes following the titles of class and subclass relating to "micro-structural devices" and "micro-structural systems". This subclass covers galvanic primary or secondary cells or batteries, fuel cells or batteries. Processes using enzymes or micro-organisms in order to: liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces ofmaterials are further classified in subclass . In classifying electrodes of hybrid cells, the individual half-cells of the hybrid cell are considered separately, e.g. an electrode in the primary half of a primary/fuel type hybrid cell is considered to be a primary-cell electrode covered by . In this group, primary cells are electrochemical generators in which the cell energy is present in chemical form and is not regenerated. In this group, fuel cells are electrochemical generators wherein the reactants are supplied from outside. In this group, secondary cells are accumulators receiving and supplying electrical energy by means of reversible electrochemical reactions. In this group, hybrid cells are electrochemical generators having two different types of half-cells, the half-cell being an electrode-electrolyte combination of either a primary, a secondary, or a fuel cell.