On non-combustibility of commercial building materials

Non-combustibility is discussed on the basis of experimental data for 66 commercial building materials obtained from two standard test methods: EN ISO 1716 oxygen bomb calorimeter and EN ISO 1182 cylindrical furnace. The sample materials are divided into five categories: concrete and ceramics, thermal/acoustic insulation materials, wall or ceiling boards, mortars and adhesives and thin coatings. To better distinguish between non-combustible and combustible materials, an effective modified heat of combustion is defined and calculated for all materials tested in both methods. The materials studied exhibited very different mass loss values and a low tendency to auto-ignite in the cylindrical furnace. Revised criteria for class A1 are proposed for better accuracy of reaction-to-fire assessment. It is proposed to use the oxygen bomb calorimeter with only one limit for the heat of combustion, that is, a value of 5MJ/kg for all materials. The proposed approach is a very efficient tool for fast and inexpensive screening for non-combustibility of building products and is expected to be a more precise method to distinguish between non-combustible and combustible materials. Copyright (C) 2016 John Wiley & Sons, Ltd.