A shortened working day does not mean 40 hours per week, as recorded in the TC, but starting at 39 and less. It is provided in several cases as provided by law. Accordingly, if you get on this list, then you have the right to demand a reduction in the number of working hours from management.

Pregnant women. Expectant mothers, regardless of their state of health, have the right to work on the day, not 8, but 7 hours with a five-day standard working week. A shortened working day for pregnant women is provided from the first trimester as soon as a woman finds out about her situation. In the future, she may ask to reduce the day to 5-6 hours if the state of health is satisfactory or poor. Also, the employer is obliged to reduce the number of hours per week to 20 if a pregnant woman works in hazardous work. The salary remains the same.
Shortened working hours may be required by mothers who have a child (children) under 14 years of age. Single mothers are given a short working day on the same basis as married women.
Women who have a disabled child of any age who lives with her. Disability in this case - the first and second groups.
Men raising a child without a wife. The same rights as a woman have a single father.
Workers with disabilities can also count on short work days.
Minor employees under the age of 18 years.
Employees of harmful production.

Additionally, the employer must enter a shorter working day before the holiday. Just do not count on a 50% reduction in hours. As a rule, employers not wanting to pay extra cash that employees did not earn, reduce the day by a maximum of 10%. At the same time, they have the right to distribute this time for the entire working week in order to replenish the norm of hours.
Employers go to other tricks. They provide a short day without talking, but they pay wages depending on hours worked. Thus, a shorter working day has a strong effect on cash payments.
To require the employer to reduce the working day, you will have to collect documents confirming the reason for the transition to new working conditions. This can be medical certificates with an opinion on the pregnancy, health status or disability of the child. You will also need to bring documents,
confirming the presence of children under 14 years old or that you bring them up alone.
Of course, you can only claim all of these rights from state-owned enterprises, while private organizations that do not work according to the labor code will most likely refuse you and you canβt do anything. Also, if you immediately ask the management for a shorter working day at the time of employment, then wait for the refusal to accept you for the position. Of course, this is not by law, but the company will find a reason why you will not be suitable as the required employee.