Definition: Evening work
The definitions of evening work and night vary considerably so that it is not easy to establish a strictly common basis for all Member States. Generally speaking, however, "evening workers" can be considered to be work done after the usual hours of working time in this Member State, but before the usual sleeping hours. This implies the possibility of sleeping at normal times (whereas "night work" implies an abnormal sleeping pattern).
Eurostat, "Labour force survey: Methods and definitions, 1998 Edition", Office for Official Publications of the European Communities, Luxembourg, 1999, p.66