BS 13501-5-2016 pdf free download.Fire classification of construction products and building elements Part 5: Classification using data from external fire exposure to roofs tests
5 Test methods
5.1 General
The four test methods given in CEN/TS 1187 are those to be used for classification purposes for roofs/roof coverings. The selection of the tests to be carried out is specified in 6.3. The classification parameters, the classes and the corresponding criteria are specified in Clauses 8 and 9.
5.2 Test 1: Method with burning brands The test evaluates the performance of a roof under the conditions of thermal attack with burning brands. The performance includes the fire spread across the external surface of the roof, the fire spread within the roof and the fire penetration.
5.3 Test 2: Method with burning brands and wind The test evaluates the performance of a roof covering under the conditions of thermal attack with burning brands and additional wind. The performance includes damaged length both on the roof covering and in the substrate.
5.4 Test 3: Method with burning brands, wind and supplementary radiant heat The test evaluates the performance of a roof under the conditions of thermal attack with burning brands, additional wind and radiant heat. The performance includes the external fire spread and the fire penetration.
5.5 Test 4: Two-stage method incorporating burning brands, wind and supplementary radiant heat The test evaluates the performance of a roof under the conditions of thermal attack with burning brands, wind and radiant heat. The performance includes the external fire spread and the penetration by fire.
6 Principles for specimen preparation, testing and classification
6.1 General requirements for specimen preparation In general, this paragraph covers tests 1, 3 and 4. Before testing, the test specimens shall be prepared and conditioned and, where relevant, mounted in accordance with the relevant test method and product standards or other technical specifications. The external fire performance of a roof/roof covering includes such aspects as external and internal fire spread, external and internal damage, fire penetration and the occurrence of flaming droplets or debris.
The external fire performance of a roof/roof covering therefore does not only depend on the burning behaviour of the exposed surface, the roof covering, but also on the influences of several components of the roof, such as the nature and thickness of insulating layers and vapour barriers together with their supporting elements. It may also depend on the systems of attachment of all components, e.g. glued or mechanically fastened. Therefore, the test specimens shall be representative, in all details of practical application with regard to:
a) substrate and deck;
b) type, the number and the joining of all layers of roofing materials (including any insulation, vapour barriers, etc.); and c) fixing of the layers. In order to reduce the amount of testing, individual test methods specify standard specimen arrangements, covering a wider field of application.
Such standard specifications concern the supporting decks and substrates, and the types and positioning of joints.
6.2 General requirements for testing
The external fire performance of a roof/roof covering does not only depend on the intrinsic properties of its components and the fire attack conditions, but also to a large extent on the pitch of the roof. In order to reduce the amount of testing, some standard pitches are defined, covering a wider field of application. However, in tests 1 and 3 a sponsor may choose none of the standard pitches, although this will limit the field of application of the classification to the pitch used for testing.
6.3 Selection of test methods
Four different test methods, representing four different scenarios, are specified in CEN/TS 1187. The methods assess the fire performance of roofs/roof coverings under the following conditions:
a) Test 1 assesses the performance of a roof under attack with burning brands;
b) Test 2 assesses the performance of a roof covering under attack with burning brands and wind;
c) Test 3 assesses the performance of a roof under attack with burning brands, wind and supplementary radiant heat;
d) Test 4 assesses the performance of a roof using a two stage test method incorporating burning brands, wind and supplementary radiant heat.BS 13501-5 pdf download.