Reaction to fire of cables as construction products
In the frame of the European Construction Products Directive (CPD), a classification system (Euroclasses) and harmonized tests for reaction-to-fire and structural fire resistance valid throughout Europe have been developed. The classification systems for various families of construction products have been published in the following parts of the European standard
EN 13501: Fire classification of construction products and building elements
- Part 1: Classification using data from reaction to fire tests; 2007+A1:2009
- Part 2: Classification using data from fire resistance tests, excluding ventilation services; 2007+A1:2009
- Part 3: Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers; 2005+A1:2009
- Part 4: Classification using data from fire resistance tests on components of smoke control systems; 2007+A1:2009
- Part 5: Classification using data from external fire exposure to roofs tests; 2005+A1:2009
- Part 6: Classification using data from reaction to fire tests on electric cables; prEN 13501-6:2011
The part 6 draft standard for electric cables is currently under approval and foreseen to be published as a standard in 2013. The reaction to fire of cables test method has been published in the standard EN 50399:2011 "Common test methods for cables under fire conditions - Heat release and smoke production measurement on cables during flame spread test - Test apparatus, procedures, results".
The classification parameters are based on flame spread and heat release, as well as on the additional classification parameters smoke production, flaming droplets/particles, and acidity; the latter are not mandatory in the EU, but may be used by Member States if required in their national building fire safety regulations. In order to have an efficient framework for CE-marking of cables, rules for extended application, EXAP, that reduce the number of tests required for a well-defined family of cables from a particular manufacturer have been developed.
The main test method used to assess the reaction to fire performance of cables is a full scale test developed in the European project FIPEC. The test apparatus consists of a test chamber with a ribbon gas burner, a vertically mounted cable bundle of 3.5 m length, and an exhaust hood where heat release and smoke production are measured.
The standardisation work has been jointly carried out by CENELEC TC20 (European Committee for Electrotechnical Standardization, TC20 Electric cables, WG10 Fire performance tests for cables) and CEN/TC 127 (Fire safety in buildings).
[1] http://www.safety-during-fire.com/cemac-ce-marking-of-cables/cemac-2-documents.html