At the request of the employee, vacation leave may be divided into parts. At least one of the parts must not be shorter than 14 consecutive calendar days (i.e. including public holidays, Sundays, etc.). With the exception of the minimum period of fourteen days, the leave may be divided into any number of parts, which may be of any length.

The obligation to provide at least 14 days of uninterrupted vacation applies to scheduled vacations and those granted at the request of the employee. In the case of splitting the leave, for example, due to an employee's illness, this requirement does not apply.

In practice, it happens that employees themselves request short leaves of absence. In such a situation, the employer has no grounds for forcing the employees to take a longer vacation.
At most, they can suggest it - especially since, according to some psychologists, a worker's real recovery is ensured only by a 3-week break from work. 

However, even if neither part of the leave lasts 14 days, there are no grounds to fine the employer. It is an offense against employee rights not to grant leave at all or to groundlessly reduce the length of leave, and not to grant leave in short portions at the request of the employee himself/herself.

Find more in the PRO HR June 2023