Judgment of the Court (Grand Chamber) of 15 July 2021.#B. K. v Republika Slovenija (Ministrstvo za obrambo).#Reference for a preliminary ruling – Protection of the safety and health of workers – Organisation of working time – Members of the armed forces – Applicability of EU law – Article 4(2) TEU – Directive 2003/88/EC – Scope – Article 1(3) – Directive 89/391/EEC – Article 2(2) – Military activities – Concept of ‘working time’ – Stand-by period – Dispute concerning the remuneration of a worker.#Case C-742/19.