We find rotation shifts every two to three days are best for workers and weekly or fortnightly rotations are the least comfortable for workers. Forward-rotating programs (moving from morning to afternoon to night shifts) are better than backward-rotating ones in terms of sleep loss and tiredness.
If someone works at night, there are rules covering the hours they work. Night time working hours are usually between 11 p.m. and 6 a.m. – but this can be flexible and should be discussed between you and us.

Câu hỏi

The word “they” in paragraph 3 refers to _______