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When does stand-by time count as working time? The European Court of Justice clarifies

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The European Court of Justice has ruled that periods of on-call time will only be working time if, on the facts, there are very significant constraints on how the workers can use their free time during them. This article reviews the judgment, and Ius Laboris lawyers in Austria comment on its impact in their jurisdiction.

The European Court of Justice has clarified the determining criteria for when a period of stand-by time or on-call time according to a stand-by system is, in its entirety, working time. This will only be the case when it follows from an overall assessment of all the circumstances that the constraints imposed on workers objectively and very significantly affect their ability to manage their free time during that period.

The case law saga concerning the issue of working time during a period of stand-by time has recently been relaunched by two of the European Court of Justice rulings of 9 March 2021. Previously, the Court had ruled that the stand-by time spent at the workplace constituted working time in its entirety, whereas the mere fact of being available to be called upon outside the workplace did not. A few years later, the Court clarified its ruling by adding that the period of stand-by time should also be considered as working time if the specific conditions of the stand-by time justify it (e.g. if the period of time within which the employee must arrive at the workplace is very short, if the frequency of interventions is high, etc.).

In its judgments of 9 March 2021, the Court clarified the outlines of its case law on taking into account the specific conditions of the period of stand-by time. The Court considered that a period of stand-by time only constitutes, in its entirety, working time when the constraints imposed on workers objectively and very significantly affect their ability to manage their free time during that period. Conversely, the Court considers that the organisational difficulties that a period of stand-by time may cause for the worker and which are the consequence of natural elements or of the worker’s free choice are irrelevant, as is the fact that the immediate environment of the place concerned is not conducive to leisure.

The first case concerned a technician who was responsible for ensuring the operation, for several consecutive days, of a transmission centre in the mountains that is very difficult to access. During the period of stand-by time, the worker was not obliged to remain in the place determined by the employer, but he had to be contactable by telephone and be able to return there within one hour, if necessary. However, given the location of the centre, the worker was, in fact, obliged to remain at his place of work, without any possibility of leisure. The Court considered that these were organisational difficulties and not constraints imposed by the employer.

The second case concerned a firefighter who had to execute periods of stand-by time according to a stand‑by system. During those periods, he was not required to be present at a place determined by his employer but had to be contactable and able to reach, if alerted, the city boundaries within 20 minutes with his uniform and the service vehicle made available to him, with which he could depart from certain rules of the highway code.

In these judgments, the Court also recalls that the classification of working time or rest periods has no effect on the system of remuneration set up by the employer in accordance with national legislation. It also has no effect on the rules on workers’ health and safety. The employer may therefore not introduce periods of stand‑by time which would jeopardise the health and safety of workers on the grounds that these periods are classified as ‘rest periods’.

Action point

In order to limit the risk of a period of stand-by time according to a stand-by system being considered as working time, certain criteria can be taken into account, such as not imposing a fixed location during stand‑by time and providing for a reasonable call-back period. The rules on health and safety at work still apply, even if the period of stand-by time is considered as a rest period.

Comment from Austria

In Austria, on-call duties are explicitly regulated by statutory law and basically exist if the employee:

  • can choose his or her own place of residence beyond the agreed regular working hours;
  • but must be reachable (by telephone); and
  • is obliged to return to work at an arranged place within a certain time frame.


The employee is therefore restricted during on-call duty in his or her leisure time activities to the extent that s/he must choose a location in such a way that s/he can arrive within the agreed period of time and return to work without being particularly impaired (e.g. by prior consumption of alcohol). As a result, on-call duty itself, unlike an agreement on standby duty (Arbeitsbereitschaft) is not yet considered as working time by Austrian law. This means it can therefore be remunerated differently and does not have to be included in the maximum amount of admissible working hours. Only those parts of on-call time in which the employee is called to an assignment during his or her on-call duty will be counted as working time (however, mere travel times between home and the place of work do not count as working time).

Summary and recommendation

Even though the Austrian statutory regulations described above still apply, in order to implement the ‘new’ criteria established by the ECJ for identifying on-call duty as working time in full it is strongly recommended employers review their current definition of on-call duties in all employment-related documents (employment contracts, guidelines etc) as well as their company practice (based on the aforementioned criteria). They should specifically examine restrictions imposed by the employer/CBA during on-call duties (especially concerning the frequency of calls and the actions required of employees, including emergency clothing etc) and to what extent these restrictions objectively affect employees’ free time to a significant extent, also taking into account the technical possibilities and the burdens on both parties.


Birgit Vogt-Majarek
Partner - Austria
Schima Mayer Starlinger
Lisa Hittinger
Associate - Austria
Schima Mayer Starlinger