1. 

By this request for a preliminary ruling, the Court is asked for guidance on the interpretation of Directive 2003/88/EC concerning working time ( 2 ) as it applies to a retained firefighter ( 3 ) who is required, on a rota basis, to be available on stand-by duty ( 4 ) within a specified radius (expressed in terms of time) of his place of work. It is also asked to advise on (i) the possibility of excluding certain categories of firefighters from the application of that directive; (ii) whether it is open to a Member State to adopt a definition of ‘working time’ that is less restrictive than that laid down under the directive; and (iii) whether the interpretation of the concept of ‘working time’ laid down under the directive also applies to the determination of remuneration in the case of persons on stand-by duty.

2.

According to Article 153 TFEU:

‘1.   With a view to achieving the objectives of Article 151, the Union shall support and complement the activities of the Member States in the following fields:

...

2.   To this end, the European Parliament and the Council:

…

...

5.   The provisions of this Article shall not apply to pay ...’

3.

Article 1 of Directive 2003/88 provides:

‘1.   This Directive lays down minimum safety and health requirements for the organisation of working time.

2.   This Directive applies to:

3.   This Directive shall apply to all sectors of activity, both public and private, within the meaning of Article 2 of [Council Directive 89/391/EEC of 12 June 1989 on the introduction of measures to encourage improvements in the safety and health of workers at work (OJ 1989 L 183, p. 1)], without prejudice to Articles 14, 17, 18 and 19 of this Directive.

…’

4.

Article 2 of Directive 2003/88 states:

‘For the purposes of this Directive, the following definitions shall apply:

…’

5.

According to Article 15 of the directive:

‘This Directive shall not affect Member States’ right to apply or introduce laws, regulations or administrative provisions more favourable to the protection of the safety and health of workers or to facilitate or permit the application of collective agreements or agreements concluded between the two sides of industry which are more favourable to the protection of the safety and health of workers.’

6.

Under paragraphs 2 and 3 of Article 17 of Directive 2003/88:

‘2.   Derogations provided for in paragraphs 3, 4 and 5 may be adopted by means of laws, regulations or administrative provisions or by means of collective agreements or agreements between the two sides of industry provided that the workers concerned are afforded equivalent periods of compensatory rest or that, in exceptional cases in which it is not possible, for objective reasons, to grant such equivalent periods of compensatory rest, the workers concerned are afforded appropriate protection.

3.   In accordance with paragraph 2 of this Article derogations may be made from Articles 3, 4, 5, 8 and 16:

…

…’

7.

The Loi du 14 décembre 2000 fixant certains aspects de l’aménagement du temps de travail dans le secteur public (Law of 14 December 2000 laying down certain aspects of the organisation of working time in the public sector; ‘the Law of 14 December 2000’) transposed Directive 93/104/EC on the organisation of working time ( 5 ) into national law. Article 3 of that law defines ‘workers’ as being ‘persons who, under a legal or contractual relationship … carry out work under the direction of another person’. Article 8 provides, inter alia, that ‘“working time” means the period during which the worker is at the employer’s disposal’.

8.

Article 186 of the Loi du 30 décembre 2009 portant sur diverses dispositions (Law of 30 December 2009 covering miscellaneous provisions) provides that, inter alia, retained firefighters are not to be defined as ‘workers’ for the purposes of Article 3 of the Law of 14 December 2000.

9.

Article 9 bis of the règlement organique du service d’incendie de Nivelles (Regulation governing the Nivelles fire service) provides:

‘During periods of stand-by duty, every member of the retained fire service serving in the Nivelles fire station must:

…’

10.

Mr Rudy Matzak is a retained firefighter ( 6 ) for the Ville de Nivelles (Town of Nivelles), Belgium. ( 7 ) Under the arrangements which apply to his engagement, he is required to be available on call for work, for one week out of every four, during the evenings and at the weekend. He is paid only in respect of time when he is on active service. Time spent on call without the firefighter being required to carry out any professional duties (so-called ‘stand-by time’) ( 8 ) is unpaid.

11.

During periods spent on stand-by duty, Mr Matzak must remain contactable and, if necessary, report to the fire station as soon as possible and in any event within no more than eight minutes under normal conditions. ( 9 ) The referring court observes that this means in practice that the firefighter must reside near the fire station and that his activities during those periods are correspondingly restricted.

12.

Taking the view that a number of aspects of the regime applying to him, including in particular his level of remuneration as regards stand-by duty, were unsatisfactory, Mr Matzak brought proceedings before the tribunal du travail de Nivelles (Labour Court, Nivelles, Belgium), which upheld the majority of his complaints by judgment of 23 March 2012.

13.

The Town of Nivelles then brought an appeal against that decision before the cour du travail de Bruxelles (Higher Labour Court, Brussels, Belgium). That court observes that, under Belgian law, working time is generally defined as time during which the worker is at the disposal of the employer and that the location of the worker does not appear to be conclusive. In the light of the interpretation by the Court of Justice of Article 2(1) of Directive 2003/88, ( 10 ) it appears to follow that the definitions of working time under Belgian law and EU law do not entirely coincide. That court also notes that there is a tendency in the national case-law to resolve the issue of the remuneration of retained firefighters such as Mr Matzak by relying, principally or exclusively, on the EU law definition of the concept of ‘working time’. Since it considers that an interpretation by the Court of Justice of certain provisions of Directive 2003/88 is necessary in order for it to resolve the dispute before it, that court has referred the following questions for a preliminary ruling pursuant to Article 267 TFEU:

14.

Written observations have been submitted by the parties to the main proceedings, the Belgian, French, Netherlands and United Kingdom Governments and by the European Commission. At the hearing on 15 December 2016, all of those parties with the exception of the Netherlands Government presented oral argument and responded to the questions put by the Court.

15.

Both the Town of Nivelles and the Commission raise issues which touch (in whole or in part) on the admissibility of the request for a preliminary ruling. ( 11 )

16.

They do so on the basis that the subject of the dispute before the referring court is the pay to which Mr Matzak is entitled in respect of his services as a retained firefighter and not the issue of his working time. Since Article 153(5) TFEU exempts matters relating to remuneration from the scope of Article 153 (which includes the improvements to workers’ health and safety to which Directive 2003/88 relates), the referring court’s questions address matters which the Court is not competent to determine.

17.

In that regard, it is settled case-law that the Court may refuse to rule on a question referred by a national court only where it is quite obvious that the interpretation of EU law that is sought is unrelated to the actual facts of the main action or its purpose, where the problem is hypothetical, or where the Court does not have before it the factual or legal material necessary to give a useful answer to the questions submitted to it. Where a question of EU law arises, there is thus a presumption of relevance. ( 12 )

18.

Does such a question arise in this case?

19.

In my view, it does.

20.

Whilst a reading of the order for reference and the national case-file submitted to the Court makes it clear that Mr Matzak’s action is essentially concerned with the question of his pay, that of itself is not determinative as to whether the Court should answer the questions referred. The question that needs to be asked in this context is not: ‘what is the subject matter of the action in the main proceedings?’ Rather, the issue is whether the interpretation of EU law that is sought is related to the actual facts of the main action or its purpose. The order for reference states that the EU law definition of the concept of ‘working time’ is relevant to resolving the issue of the remuneration of retained firefighters such as Mr Matzak. ( 13 ) This Court’s interpretation of that concept will thus assist the referring court in determining the case before it. On that basis, the questions referred are admissible. ( 14 )

21.

Although Article 2 of Directive 2003/88 defines ‘working time’ by reference, inter alia, to periods during which a ‘worker’ is ‘working’, the directive does not define the notion of ‘worker’ itself.

22.

In its written observations and at the hearing, the French Government referred to the situation in France, where it submits that all firefighters who are not professional are engaged on a basis which does not involve a relationship of subordination and whereby they are not paid a wage or salary, as such. Rather, they receive an allowance (‘indemnité’), which is not subject to tax or social security deductions. Similarly, the Belgian Government states that retained firefighters in that Member State are not classified as workers for the purposes of the relevant provisions of national law, ( 15 ) but instead have the status of ‘paid volunteers’ (‘bénévolat indemnisé’).

23.

Does this mean that those firefighters do not fall to be classified as ‘workers’ for the purposes of the directive?

24.

The Court has held that the notion of ‘worker’ under the directive is an autonomous concept of EU law. ( 16 ) It should be interpreted as meaning ‘any person who pursues real, genuine activities, to the exclusion of activities on such a small scale as to be regarded as purely marginal and ancillary’. The essential feature of an employment relationship is that for a certain period of time a person performs services for and under the direction of another person in return for which he receives remuneration. ( 17 ) The Court has not had to address the question of what constitutes ‘remuneration’ (or ‘pay’) for the purposes of that definition. Some guidance may however be drawn from the terms of Article 157(2) TFEU (in the context of equal pay), which defines ‘pay’ by reference to sums ‘… which the worker receives directly or indirectly in respect of his employment, from his employer’. ( 18 )

25.

More specifically, the Court has found that the directive applies to professional firefighters. ( 19 ) As regards its extension to firefighters of other categories, I would observe that there is no suggestion in the order for reference that firefighters in Mr Matzak’s category are not pursuing a real and genuine activity and that they are not ‘under the direction of another person’ in the form of the fire service. ( 20 ) If the latter is to function effectively, all members of the firefighting team (be they professional firefighters, retained firefighters or volunteer firefighters) must clearly work under directions and follow orders that are given, including holding themselves available for active service on a rota basis. As regards the question whether the sums which Mr Matzak receives in return for his services constitute ‘remuneration’ or ‘pay’ for the purposes of the test set out in point 24 above, apart from the (relatively unfocused) submissions of the Belgian Government, the Court has been provided with little information as to the precise arrangements which govern the position in that Member State and it is thus not possible to comment further. That issue will fall to be determined by the national court, applying the test I have just referred to. Since the concept of ‘worker’ is an EU one, the precise designation of the status of the person providing services and categorisation of the money he receives for providing those services under national law cannot by definition be conclusive.

26.

By Question 1, the referring court essentially asks whether it is open to Member States to exclude certain categories of firefighters from all the provisions transposing Directive 2003/88 into national law, including the provisions defining working time and rest periods.

27.

Those definitions are set out in Article 2 of the directive. As is apparent from the wording of Article 17(3) of Directive 2003/88, it is only those provisions expressly referred to therein which may be the subject of a derogation in relation to, inter alia, fire services. ( 21 ) Thus, Article 17(3) provides that it is open to a Member State which satisfies the requirements laid down in Article 17(2) to derogate from Articles 3, 4, 5, 8 and 16 of the directive. That facility does not extend to the definitions of ‘working time’ and ‘rest period’ laid down in Article 2 and, since Article 17(3) must, in the same way as all derogating provisions, ( 22 ) be strictly construed there is in my view no scope for adopting an extensive approach which might go beyond the express wording of the derogation. ( 23 )

28.

I therefore consider that the answer to Question 1 should be that Article 17(3)(c)(iii) of Directive 2003/88 should be interpreted as meaning that it enables Member States to exclude certain categories of firefighters recruited by the public fire services only from the provisions of that directive set out in Article 17(3). It does not enable Member States to exclude those workers from all the provisions transposing that directive and, in particular, it does not enable the provisions that define ‘working time’ and ‘rest period’ to be excluded as regards those workers.

29.

By Question 2, the referring court asks whether, since Directive 2000/88 lays down only minimum requirements, it can be interpreted as not preventing a Member State from adopting a less restrictive definition of ‘working time’.

30.

The Belgian Government argues that this question is inadmissible, observing that the Belgian Cour de cassation (Court of Cassation) has held on several occasions that the concept of working time is to be given the same interpretation under Belgian law as under EU law, and that the referring court has at its disposal all the material necessary for it to comprehend that notion. It relies in particular in that regard on Dzodzi, ( 24 ) arguing that paragraph 42 of that judgment is authority for the proposition that there must be an actual risk of divergence between EU law, on the one hand, and a provision of national law which refers to a provision of EU law, on the other hand, for the Court to be competent to give a ruling under Article 267 TFEU in such circumstances.

31.

I have already indicated that there is a presumption of relevance where this Court is asked to interpret a provision of EU law. ( 25 ) I see no reason to depart from that presumption here. The referring court has indicated that questions concerning the remuneration of retained firefighters under national law are liable to be resolved on the basis of the EU law definition of ‘working time’. ( 26 ) An answer to Question 2 is anticipated to assist the referring court in deciding the case before it. On that basis, this Court should provide that answer. As regards the application of Dzodzi, the Court has held in subsequent case-law that it has jurisdiction to give a ruling where the facts of the cases being considered by the national courts were outside the scope of EU law but where the provisions concerned had been rendered applicable by domestic law (by virtue of a renvoi to EU law) and where the domestic provisions at issue did not limit application of the latter. ( 27 ) In the present case, it seems to me that the national position as described in the order for reference involves a renvoi to EU law which does not limit its application. For that reason, I reject the Belgian Government’s argument. It seems to me that the point is one which this Court is competent to answer and that it should accordingly do so.

32.

Turning to the question itself, at first sight it may appear to demand an affirmative response. It is true that Article 1 of Directive 2003/88 provides that the directive lays down minimum safety and health requirements and that, as both Mr Matzak and the Commission point out, Article 15 entitles the Member States to apply or introduce provisions which are more favourable to the protection of the safety and health of workers. Furthermore, the definition of ‘working time’ set out in Article 2 expressly states that regard is to be had to ‘national laws and/or practice’.

33.

The true position is, I think, more complicated. In adopting Directive 2008/33, the (then) Community legislature was seeking to lay down minimum standards to be applied throughout what is now the European Union. ( 28 ) It did so by providing, inter alia, a definition of ‘working time’, coupled with that of ‘rest period’, that was intended to be uniform throughout the Member States. It follows that those definitions must be construed in accordance with objective characteristics by reference to the scheme and purpose of the directive, since only such an interpretation is capable of securing for the directive full efficacy and uniform application of those concepts in all the Member States. ( 29 ) There is thus no leeway for a Member State seeking to implement the directive to adopt a less restrictive version of either of those definitions.

34.

That does not mean, of course, that it is not open to a Member State to enhance the protection afforded by the directive using different legislative techniques. Member States may, for example, provide for longer minimum rest periods than those laid down in Articles 3 to 7 of the directive in exercise of the rights which Article 15 affords them. The same will be true of the provisions governing night and shift work in Articles 8 to 13. But the Member States must retain the definitions of ‘working time’ and ‘rest period’ laid down under Article 2 if they do so.

35.

I therefore consider that the answer to Question 2 should be that Directive 2003/88 is to be interpreted as preventing the national legislature of a Member State from retaining or adopting a definition of ‘working time’ that is less restrictive than that laid down under the directive. However, the legislature of that Member State may enhance the protection afforded to workers provided that, in so doing, it does not depart from the terms of that definition.

36.

By Question 3, the referring court asks whether Article 2 of Directive 2003/88, in so far as it defines what the referring court terms ‘the principal concepts used’ in the directive, including in particular those of ‘working time’ and ‘rest period’, can be construed as not applying to the concept of working time which is used to determine the remuneration paid to firefighters such as Mr Matzak.

37.

In order to answer this question, it is necessary to delimit its terms. First, so far as is here relevant, Article 2 of Directive 2003/88 does not define time concepts other than ‘working time’ and its corollary, ‘rest period’. Whether the definition of ‘working time’ extends to cover circumstances such as those of workers in Mr Matzak’s situation is the subject of the referring court’s fourth question.

38.

Second, it is plain beyond doubt that this Court’s role under the Article 267 TFEU procedure is limited to providing an interpretation of EU law. It cannot interpret national law, that being a matter which is entirely for the courts of the Member State concerned. ( 30 ) Thus, whilst the referring court states that there is a tendency in the national case-law to resolve the issue of the remuneration of retained firefighters by relying on the EU law definition of the concept of ‘working time’, ( 31 ) the operation of those rules under domestic law is not an issue which this Court can address. Provided that national rules are compliant with EU law, it is open to the Member States to structure the national legislation at issue as they see fit, and for their national courts to interpret it. I shall therefore address (only) issues of EU law in my analysis of this question.

39.

In the light of those observations, it seems to me that Question 3 is best understood as asking whether the definition of ‘working time’ set out in Article 2 of Directive 2003/88 also applies, automatically and without more, so as to regulate the pay of workers entitled to benefit from the protection in terms of safety and health which that directive affords.

40.

In my view, no such automatic link exists.

41.

Directive 2003/88 was adopted on the basis of what is now Article 153(2) TFEU. That provision gives the EU legislature power to adopt directives laying down minimum requirements for gradual harmonisation as regards (in so far as relevant to this Opinion) health and safety (Article 153(1)(a)), working conditions (Article 153(1)(b)) and social security and social protection (Article 153(1)(c)). Paragraph 5 expressly records that ‘the provisions of this Article shall not apply to pay’. The latter is thus a matter for the Member States alone. ( 32 )

42.

That division of powers is also reflected in the Court’s case-law. In Dellas and Others, the Court observed, as regards Directive 93/104, that both the purpose and the actual wording of the directive led to the conclusion that it did not apply to the remuneration of workers. It went on to add that such an interpretation followed unambiguously from what is now Article 153(5) TFEU. ( 33 ) In Vorel, the Court confirmed the application of that principle in relation to Directive 2003/88. ( 34 )

43.

That on its own could be said to answer Question 3. However, as the Netherlands Government rightly observes, although Directive 2003/88 does not require that the Member States apply the definition of ‘working time’ to questions of remuneration, it also does not provide that they may not do so. Thus a Member State may competently enact domestic legislation which provides that the remuneration of one or more categories of worker is to be based on that definition. Contracts of employment and collective agreements also typically use ‘working time’ in conjunction with the number of hours worked and agreed rates of pay to establish overall remuneration. Such rates of pay may also differ depending on the type of working time (active service time, on-call time) at issue. ( 35 ) All that is a matter for national law.

44.

I therefore consider that the answer to Question 3 should be that the definition of ‘working time’ set out in Article 2 of Directive 2003/88 does not apply, automatically and without more, so as to regulate the pay of workers entitled to benefit from the protection in terms of safety and health which that directive affords. However, although that directive does not require that the Member States apply the definition of ‘working time’ to questions of remuneration, it also does not provide that they may not do so. It follows that it is open to a Member State to enact domestic legislation which provides that the remuneration of one or more categories of worker is to be based on that definition.

45.

By Question 4, the referring court is essentially asking whether the definition of ‘working time’ in Article 2(1) of Directive 2003/88 should be interpreted as extending to workers, such as Mr Matzak, who are engaged on stand-by duty and are required to be able to respond to calls from their employer within a short period of time (in this case, eight minutes) without being required at the same time to be physically present at the employer’s premises and whose opportunities to undertake other activities during the period in question may accordingly be limited.

46.

As a preliminary point, I should mention that, although the referring court words its question on the basis that the on-call time is ‘undertaken at the home of the worker’, the actual requirement referred to in the order for reference is not that the time be spent at the worker’s home but rather that he be able to reach his place of work within eight minutes. ( 36 ) That said, it may well be the case in practice that workers do spend their time at home during periods of stand-by time and that they may, as a direct result of that requirement, need to have their home within the area which that limitation imposes.

47.

Turning to the substance of the question, Mr Matzak argues that the facts of the case, coupled with the Court’s case-law, mean that his periods of stand-by time clearly represent working time. In particular, the fact that he may not be required to carry out any actual duties while on call is irrelevant. He is required to be at the disposition of his employer, and contactable, at all times and his freedom of movement and freedom to organise his own affairs are accordingly severely constrained during his periods of duty. Failure to comply with those requirements can lead to disciplinary, and possibly penal, sanctions. Mr Matzak’s situation, involving as it does a duty to present himself at his workplace within a very short time is in fact more constrained than that of a worker who is on call but allowed a considerably longer period of time to do so or who may intervene from a distance. It follows that he must be regarded as being at his employer’s disposal at all relevant times.

48.

Whilst I see, at least to a degree, the logic of those submissions, I do not believe the position to be as straightforward as Mr Matzak suggests.

49.

The starting point for any analysis must in my view be the wording of Article 2(1) and (2) of Directive 2003/88. This defines ‘working time’ as being ‘any period during which the worker is working, at the employer’s disposal and carrying out his activity or duties …’ and ‘rest period’ as meaning ‘any period which is not working time’. As a number of parties submitting observations, and indeed the Court in its case-law, have observed, the distinction is thus a binary one: either time is working time or it is not. ( 37 ) The legislature has not seen fit to set out any further category or categories, thereby allowing for some degree of refinement or subtlety. That lack of flexibility is perhaps regrettable; but the text of the law is what it is.

50.

Since the category of ‘rest period’ is by definition a residual one, I shall concentrate in the following analysis on the notion of ‘working time’. Some guidance as to how that should be construed can already be found in the Court’s case-law.

51.

Thus, the Court has repeatedly held that the concept of ‘working time’ under Directive 2003/88 is an autonomous concept of EU law, which must be defined in accordance with objective considerations by reference to the scheme and purpose of that directive, intended to improve workers’ living and working conditions. ( 38 ) It requires that three conditions be satisfied. First, the worker must be ‘at work’; second, he must be at the employer’s disposal; and, third, he must be carrying out his activity or duties. ( 39 )

52.

The first occasion on which the Court was called upon to construe those requirements was in Simap. ( 40 ) The case concerned the on-call time of doctors in primary care teams working at a health centre. For some of that time, they were required to be present at their place of work whilst for the remainder they needed merely to be ‘contactable’. The Court held that there was an essential difference between the two. As regards the former, even if the activity performed might vary according to the circumstances, the fact that the doctors were obliged to be present and available at the workplace with a view to providing their professional services meant that they were carrying out their duties. The requirements of Article 2(1) were accordingly satisfied. For the purposes of the latter, however, and even if they were at the disposal of their employer inasmuch as it must be possible to contact them, the doctors could manage their time with fewer constraints and pursue their own interests. That time thus fell within the category of ‘rest period’. ( 41 )

53.

Jaeger ( 42 ) concerned a hospital doctor who was obliged to spend his time on call at his employer’s premises. He was allocated a room with a bed in which he could sleep when his services were not required. The Court repeated its observations in Simap, ( 43 ) but noted that no ruling had been given in that case as regards circumstances where it was open to the worker to rest or sleep when on duty at the employer’s premises. It held that the point was irrelevant. What it termed the ‘decisive factor’ was that the worker was required to be present at the place determined by the employer and to be available to the employer in order to be able to provide his services immediately in case of need. It followed that the worker could not be said to be ‘at rest’ during the periods in question. ( 44 ) In responding to the national court’s question, however, the Court made it clear that its ruling applied to a situation in which the worker was ‘required to be physically present in the hospital’. ( 45 ) The workers in question were significantly restricted in how they could manage their time and were separated from their family and social environment. The Court added that its interpretation of the notion of ‘working time’ could not be called into question by objections based on the economic and organisational consequences which certain Member States had argued would arise if such time were classified as ‘working time’. ( 46 )

54.

In Dellas, ( 47 ) which likewise involved a requirement for special needs workers to spend periods of on-call time at the employer’s premises, the Court reached an identical conclusion to the one set out in Jaeger.

55.

Grigore ( 48 ) involved a forestry worker who was provided with staff accommodation by his employer, located in the area of the forest for which he was responsible. He was required to spend periods of time there. ( 49 ) The Court held that the provision of that accommodation was not of itself conclusive evidence that time spent there constituted working time by sole reason of the fact that it was located within Mr Grigore’s duty area; however, if the true position was that he was under a duty to be immediately available to his employer in order to provide the appropriate services in case of need, the definition of that concept would be satisfied. ( 50 )

56.

Lastly, ( 51 ) in Federación de Servicios Privados del sindicato Comisiones obreras (‘Tyco’) ( 52 ) the Court was asked to consider the question whether time spent by workers having no fixed or habitual place of work travelling between their home and their employer’s customers, as designated by their employer, constituted ‘working time’. The Court held that it did. It noted, in particular, the principle which finds its origin in Jaeger that the decisive factor in determining whether the definition is satisfied is the requirement to be present at the place determined by the employer and to provide the appropriate services immediately. At the same time, it stressed the dicta laid down in Simap that the possibility for workers to pursue their own interests is a factor capable of demonstrating that the period in question is not working time for the purposes of Directive 2003/88. That was not the case with the workers in the main proceedings, however; notwithstanding the fact that they had a certain freedom when travelling, they nonetheless were compelled to act on their employer’s instructions during the periods in question. ( 53 )

57.

It seems to me that the statement that ‘the requirement to be present at a place determined by the employer to provide the appropriate services immediately’ is the ‘decisive factor’ in determining what is, and is not, working time should be read with a degree of caution. Plainly, it applied in cases such as Jaeger and Dellas, where the obligation was to spend time on stand-by at the employer’s premises. The fact that the worker might not spend all of that time actually working was irrelevant. Equally, though, it was not conclusive in Grigore, where the Court also placed emphasis on the degree of freedom enjoyed by the worker. Indeed, that aspect lay at the heart of the Court’s ruling in Simap. It seems to me that the quality of the time that the worker may enjoy when on stand-by duty (as evidenced by, for example, his ability to devote himself to his own interests and family) ( 54 ) is of equal relevance. The fact that, in any given case, a worker may be required to spend stand-by time within a radius that is relatively close to his place of work does not in my view detract from the need to have proper regard to the quality of the time he may spend. Save where a worker may be able to intervene remotely, it is of the nature of that type of duty that he may be under an obligation to remain close to his place of work. It is the quality of the time that is spent rather than the precise degree of required proximity to the place of work that is of overriding importance in this context. It is for the referring court, as sole judge of the facts, to determine whether the quality of Mr Matzak’s stand-by time was undermined to such a degree by any restrictions imposed by his employer that it should be classified as working time.

58.

I therefore consider that the answer to Question 4 should be that the definition of ‘working time’ in Article 2(1) of Directive 2003/88 should not be interpreted as extending automatically to workers engaged on stand-by duty who are required to be able to respond to calls from their employer within a short period of time (without being required at the same time to be physically present at the employer’s premises) and whose opportunities to undertake other activities during the period in question may accordingly be limited. Rather, it is necessary to have regard to the quality of the time that the worker may enjoy when on that type of duty, in the form of, for example, his ability to devote himself to his own interests and family. It is the quality of the time that is spent rather than the precise degree of required proximity to the place of work that is of overriding importance in this context. Whether or not such time falls to be classified as ‘working time’ in a particular case will be a matter for the national court to decide on the facts.

59.

In the light of all the above considerations, I am of the opinion that the Court should answer the questions raised by the cour du travail de Bruxelles (Higher Labour Court, Brussels, Belgium) as follows: