BS EN 12446:2011 pdf download – Chimneys — Components — Concrete outer wall elements
8.2 Heat shock resistance
8.2.1 Following the heat stress resistance test required in 8.1, when an outer wall element designated as soot fire resistant is tested as described in A.1.4 to a flue gas temperature of 1 000 °C for a period of 30 min ± 1 min, the element shall subsequently meet the requirements of 8.4. When an outer wall element has multiple passages with an equal wall thickness, the heat shock test shall be carried out on the passage with the highest temperature designation. NOTE The test described in A.1.4 is the method used to assess the sootfire resistance.
8.2.2 Bends or fittings, made of the same material mix and by the same method of manufacture as the tested straight outer wall element, shall be deemed to conform to 8.2.1.
8.2.3 Outer wall elements, made of a different material mix or using a different method of manufacture from those described in 8.2.2, shall be checked for heat shock resistance by testing a special straight test sample in accordance with 8.2.1. This straight test sample shall be made using the same material mix and manufacturing method as the outer wall elements.
8.2.4 The maximum temperature measured on the surface of adjacent combustible materials shall not exceed 100 °C when related to an ambient temperature of 20 °C, when test assembly is tested at the test temperature of 1 000 °C over a period of 30 min. The manufacturer shall declare the distance to the combustible partition and whether the gap between the outer wall element and the adjacent combustible partition is opened or closed. This distance shall not exceed the distance determined as described in 8.1.5.
8.3 Thermal resistance Thermal resistance shall be measured according to the method given in A.4 of EN 1858:2008 (reference method) or calculated according to the method given in Annex C of EN 1858:2008 and the value obtained declared. 8.4 Compressive strength 8.4.1 When tested as described in A.8 of EN 1857:2010, straight outer wall elements shall withstand an intensity of loading equivalent to 4 times the manufacturer’s declared structural height before subjecting the element to the thermal performance test(s) and three times the manufacturer’s declared structural height after subjecting the element to the thermal performance test(s). 8.4.2 Outer wall element bends and fittings made of the same material mix and by the same method of manufacture as the tested straight elements shall be deemed to conform to 8.4.1.
8.4.3 Outer wall elements made from a different material mix, or using a different method of manufacture from those described in 8.4.2, shall be checked for compressive strength by testing a special straight test sample in accordance with 8.4.1. This special straight test sample shall be made using the same material mix and manufacturing method as the bend or fitting.
8.5 Bulk density When outer wall elements are tested as described in A.10 of EN 1857:2010, the lowest and highest bulk density value shall be within a tolerance of ± 10 % of the manufacturers declared bulk density for the outer wall element.
8.6 Freeze-thaw resistance Where national regulations require freeze/thaw resistance of wall elements, they shall be tested in accordance with EN 14297. The product shall not present any damage of type 7, 8, 9 and 10 in accordance with EN 14297:2004, Table 1.
8.7 Flexural strength under wind loading
The manufacturer shall declare the maximum free standing height of outer wall elements.
Without testing, this shall be no greater than 4,5 times the least lateral overall external dimension of the outer wall element from the last point of lateral support, see Figure 2.
Alternatively, the free standing part of the outer wall element above the last lateral support shall withstand a wind load of 1,5 kN/m 2 (or a value according to national regulations) when tested in accordance with A.2.
8.8 Gas tightness of passages used for combustion air The gas tightness of the passage of an outer wall element, which is to be used for the air supply duct of a room sealed chimney application, shall be at least N2 (as defined in EN 1857) when measured after thermal testing. The gas tightness test shall be carried out in accordance with A.3.
8.9 Resistance to fire external to external Where national regulations require resistance to fire external to external (see EN 1443) of outer wall elements, they shall be evaluated and declared in accordance with those regulations.
8.10 Dangerous substances Materials used in products shall not release any dangerous substances in excess of the maximum permitted levels specified in a relevant European Standard for the material, or permitted in the national regulations of the member state of destination.