485190300478698 6426PT1-82 6426/1 International Standard ISo INTERNATIONAL ORGANIZATION FOR STANDARDIZATION+MEXAYHAPOAHAR OPTAHW3AUMR NO CTAHAAPTM3AIWM+ORGANISATION INTERNATIONALE DE NORMALISATION Horological vocabulary Part 1 : Technical and scientific definitions Vocabulairehorloger-Partie1:Definitionstechnico-scientifiques First edition-1982-02-01 ISO 6426/1-1982 (E) UDC681.11:001.4 Ref.No.1SO6426/1-1982(E） Descriptors : clock making, time measuring instruments, vocabulary, definitions, formulas (mathematics). Price based on 7 pages PT 1-2 192h9 EOGTSh 4 Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (ISo member bodies). The work of developing Inter- national Standards is carried out through ISo technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. Intrnational Standard ISO 6426/1was sdevelopedbyTechnical Committee ISO/TC 114, Horology, and was circulated to the member bodies in May 1980. Australia Japan Czechoslovakia Romania Egypt, Arab Rep. of Spain France Switzerland India USSR The member bodies of the following countries expressed disapproval of the document on technical grounds : Germany, F.R. United Kingdom International OrganizationforStandardization,1982 Printed in Switzerland ISO6426/1-1982 (E) INTERNATIONALSTANDARD 6426PT 1-82 EOGTSh 0047871 6 Horological vocabulary Part 1 - Technical and scientific definitions Scopeandfield of application in the dates, taken in this order, of the end of the interval (hj and the beginning of it (h;). This part of ISO 6426 defines the principal technical and scien- NOTE In a uniform time scale, by applying formula (1), the expres- tific terms used in the horological industry. These definitions apply to time-measuring instruments or to related devices sion of the duration is given by the relation : T = ^(tj - t) . . . (3) A table summarizing the values and units of measurement associated with the definitions is given at the end of this part of or even more simply, if = 1, that is if the uniform time scale ISO6426. serves as a reference : NOTE - The definitions of technical and commercial terms will form T=tj-ti .. . (4) the subject of a future International Standard. In this case, there is a pure and simple identity between h and t 2Reference when the indices agree and the unit of duration is the second as defined in the international system (Sl). If, in addition, the in- Iso 31/1,Values and units of space and time. dices are themselves chosen from a completely ordered whole (hjl. 3 Definitions state (E) of an instrument at the instant t;: The dif- The order in which the terms are given is a logical order, ference at a precise marked instant ti, between the date hi without any intention of classification and the numbering of the which it indicates and the reference date H; definitions does notindicateanyscale of importance. E; = h - H; . . . (5) 1 time : Undefined medium in which existing objects appear to develop irreversibly in the changes which they undergo, and The unit of the state is the second. in which events and phenomena appear to occur in their suc- cession. NOTE -- If there is direct access to a reference scale of time main- tained by a standard clock for the purpose of marking a date H, the To this medium corresponds a quantity t allowing, over a time checking of a time-keeping instrument maintaining its own scale of scale, the chronological order of events. time h by comparison with the standard consists of dating, that is by simultaneously marking the same event in two scales of time. dat