This part of EN 1366 specifies a test method for determining the fire resistance of smoke extraction ducts that are used for single compartment applications only. In such applications, the smoke extraction system is only intended to function up to flashover (typically 600 °C). This method of test is only suitable for ducts constructed from non-combustible materials (euro class A1 and A2-s1, d0).It is applicable only to four sided and circular ducts. One, two and three sided ducts are not covered.This test has been designed to cover horizontal smoke extraction ducts intended for single compartment applications only.This test method of part 9 is applicable on