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ISO 19700:2007 pdf free

ISO 19700:2007 pdf free.Controlled equivalence ratio method for the determination of hazardous components of fire effluents
Since the yields of products in fires depend upon the decomposition conditions (references [1] to [5]), it is possible to examine the relationships between product yield and a range of variables affecting the decomposition conditions using this apparatus and the methodology described. The specified test conditions represent a minimum set designed to obtain data for oxidative pyrolysis under non-flaming conditions, for well-ventilated flaming conditions at an equivalence ratio of less than 0,75, and for vitiated flaming conditions at an equivalence ratio of more than 2. The test is designed to replicate real fire conditions, and it is essential that proper observations are made to ensure that those conditions are being met.
Samples of a material or product are combusted under steady-state conditions in one or more of four environments whose temperature and equivalence ratio are representative of a particular stage of a fire. The four types of fire to be represented are: oxidative pyrolysis, well-ventilated flaming developing fires, small flaming vitiated fires, and post-flashover vitiated fires, as defined in ISO/TS 19706.
In the oxidative pyrolysis mode, the furnace temperature is set below the auto-ignition temperature. The three flaming modes are accomplished by using vapour temperatures above typical auto-ignition temperatures. For flaming decomposition conditions, different fuel-to-oxygen ratios, and hence different equivalence ratios, are obtained when different, constant primary air flows are used in relation to the constant rate of introduction of the fuel. To achieve the required gasification rates, materials may be combusted under different conditions from each other.
The secondary, dilution air is added to generate a greater sample flow and cooler effluent which permits a large number of gas and smoke sampling procedures to be used without the need for a large number of replicate tests.
The requirement in each test run is to obtain stable, steady-state decomposition conditions for at least 5 min during which the concentrations of effluent gases and particles can be measured. The time taken for steady-state conditions to be established varies, depending upon the nature of the test specimen and the test
conditions.ISO 19700 pdf download.

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