BS ISO 3159:2009

This standard BS ISO 3159:2009 Timekeeping instruments. Wrist-chronometers with spring balance oscillator is classified in these ICS categories:

• 39.040.10 Watches

This International Standard lays down the definition of the term “chronometer”, describing the categories, the test programme and the acceptable minimum requirements for wrist-chronometers.

NOTE Wristwatches using a tuning fork oscillator are subjected to these tests pending the availability of separate standards.