Insulated Zone Fire Curtains

Many Building Control Officers, in London, are requesting that we use a fire curtain that has a minimum of 30 minutes integrity and also insulating zone of 30 minutes. This is the PAS 121 standard. During our fire tests the temperature on the safe side of the fire curtain rose only by 45 degrees Celsius, at a point 10cm away from the curtain. This is after 30 minutes and about 1000 degrees Celsius on the fire side.