There's further concern over conditions in schools as the cold snap looms on the horizon.
Under current Department Covid-19 guidelines, windows and doors in schools must be kept open at all times to allow adequate ventilation.
However many parents are said to be worried for their children's health coming into the winter and having to sit in a potentially freezing classroom.
The Department is set to issue new advice this week as it relates to ventilation in schools.
Assistant General Secretary with the TUI Joanne Irwin has been outlining the changes to be introduced: