BS ISO 10553:2018,Horology — Procedure for evaluating the accuracy of quartz watches.
BS ISO 10553:2018 applies to quartz watches having accompanying documents on which the accuracy classification is indicated.
Normative references
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document.
ISO 3158, Timekeeping instruments- Symbolization of control positions;
ISO 16269-6: 2014, Statistical interpretation of data Part 6: Determination of statisticaltolerance intervals;
The main factors affecting the operating accuracy of quartz watches are temperature and ageimg.Accordingly, these two factors are taken into account when evaluating the accuracy, the influence of other factors, such as mechanical impacts, magnetic fields, humidity and supply voltage is low.
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