I came across this video, from Dorset Fire & Rescue Service. It shows a fire test on two different types of doors. One is a UPVC door and the other is a fire door.
The fire is started behind the fire door and then some 30 seconds later a fire is initiated behind the UPVC door. Both doors are now closed and we wait for the effects of the fire to take place.
Initially, it does appear that the fire door is leaking more smoke at 4:30 seconds.
However, at 6:30 seconds, you can see the lower section of the UPVC door start to disfigure from the intense heat. The fire door remains the same with smoke getting through the top section of the door.
At 9mins the lower panel section of the UPVC door has developed an opening, allowing smoke to disperse rapidly. The fire door has stayed relatively the same.
At 11mins, the lower panel of the UPVC door has completely disintegrated, and the flames are bellowing out. The fire door has smoke escaping from the top and on one side of the door, but the door is intact and not warped in any way.
At 12mins the UPVC door has completely disintegrated top and bottom. However, the fire door is still holding back the fire and showing little signs of any structural defects.
After the fire was extinguished you can see there is no longer a UPVC door. The fire door is still in place, charred, but fully intact.
What this kind of test highlights, is it is important to make sure you have the correct type of door protecting your escape routes and fire compartments. Furthermore, it is important that your fire doors are not wedged open and have the appropriate self-closing device.