A fire insulation rating is a measure of time that a specific component or system can withstand the heat generated from a fire and prevent it from breaching the building’s compartmentation.
In a BS EN1366-3 test, there should be no individual hotspots of 180°C, or an average increase of 140°C, on the construction, services, or seal on the non-fire side. For context, it is worth understanding that inside the furnace (fire side), the temperature can exceed 1000°C.
The letter “I” is used to measure a fire insulation rating, and the measure is in minutes. For example, EI 30 represents 30 minutes/ half-hour integrity and insulation, and EI 240 represents 240 minutes / 4 hours integrity and insulation.