ANNEX I CU.K.Requirements for construction, testing, installation, and inspection
4.CONSTRUCTION AND FUNCTIONAL REQUIREMENTS FOR TACHOGRAPH CARDSU.K.
4.5 Data storage U.K.
4.5.3 Driver card U.K.
4.5.3.1 Tachograph application (accessible to first and second generation vehicle units) U.K.
4.5.3.1.9Driver activity dataU.K.
(267)The driver card memory shall be able to hold driver activity data for at least 28 days (the average activity of a driver is defined as 93 activity changes per day).U.K.