Non-standard Working Day
An unregulated workday is a special working regime under which certain employees may be occasionally called upon by the employer, at their discretion, to perform their job duties outside the established duration of working hours. The list of positions with an unregulated workday is determined by collective agreements, agreements, or a local regulatory act adopted taking into account the opinion of the representative body of employees.
Source: "Labor Code of the Russian Federation" dated December 30, 2001, No. 197-FZ (as amended on December 3, 2012)