ventilation

The landlords said they thought the faulty ventilation system served the whole block, but after finding out this was not the case a specialist company was contacted to have the system checked and repaired.

Postdoctoral researcher Dr. Mojtaba Zabihi, the study's first author, explains that room configurations and existing heating, ventilation and air conditioning systems can differ widely.

By midnight, the fire had been extinguished, with ventilation fans used to clear smoke.

It can take thousands of workers to build a plant, with large amounts of steel and concrete and several systems for cooling, ventilation and controls needed.

But poor ventilation can also be caused by structural problems like roof leaks or poor drainage, she says - and landlords have a responsibility to address these root causes.