Calculation of the critical times of carbon monoxide influence on humans in case of fire in the premises

A mathematical model of calculating the content of carboxyhaemoglobin in the blood of humans exposed to CO has been proposed. Results of comparing the calculation of carboxyhaemoglobin content with the experimental data of human exposure to constant concentration of CO during quiet breathing have been obtained. Results of numerical experiments for determining carboxyhaemoglobin concentration in case of rapid pulmonary ventilation that is characteristic for fire conditions in a room have been shown. The estimates of intervals of CO influence on the human body have been obtained with the use of the analytic solution of the integral model for calculating thermogasdynamics of fire. Critical fire durations obtained with the use of the proposed model and the traditional approach have been compared. It has been shown that the method of calculating the critical fire duration in terms of CO that exists in the scientific and regulatory literature on fire safety can lead to qualitatively and quantitatively incorrect results. © 2017 International Information Institute

Calculation of the critical times of carbon monoxide influence on humans in case of fire in the premises

A mathematical model of calculating the content of carboxyhaemoglobin in the blood of humans exposed to CO has been proposed. Results of comparing the calculation of carboxyhaemoglobin content with the experimental data of human exposure to constant concentration of CO during quiet breathing have been obtained. Results of numerical experiments for determining carboxyhaemoglobin concentration in case of rapid pulmonary ventilation that is characteristic for fire conditions in a room have been shown. The estimates of intervals of CO influence on the human body have been obtained with the use of the analytic solution of the integral model for calculating thermogasdynamics of fire. Critical fire durations obtained with the use of the proposed model and the traditional approach have been compared. It has been shown that the method of calculating the critical fire duration in terms of CO that exists in the scientific and regulatory literature on fire safety can lead to qualitatively and quantitatively incorrect results. © 2017 International Information Institute

Некоторые особенности определения показателя токсичности при стабилизированном горении жидкости в помещении

Analysis of thermal gas dynamic conditions of conducting experiments to determine toxicity of combustion products in case of fire in a room was carried out. Mathematic models to calculate options of heat and mass transfer in characteristic small-scale and large-scale rooms was considered.В статье приведены результаты анализа термогазодинамических условий проведения экспериментов по определению токсичности продуктов горения при пожаре в помещении. Рассмотрены математические модели расчета параметров тепломассообмена в характерных мелкомасштабных и крупномасштабных помещениях

Gas thermodynamic conditions of cold air entrainment by natural smoke exhaust system in case of compartment fire

Conditions of occurrence of abnormal operation of natural smoke exhaust system are analyzed when cold air is entrained into smoke exhaust windows preventing extraction of smoked heated gas layer beneath a ceiling (also known as plugholing). Analytical equation is derived for prediction of critical average volumetric temperature of gas layer beneath a ceiling when plugholing starts with consideration for the height of smoke exhaust window. This equation was compared with published experimental data and with numerical experiments using 3D field model of fire gas thermodynamics. It was found that the height of smoke exhaust window exerts significant influence on occurrence of plugholing and on maximum bulk flow rate of combustion products extracted from compartment via the window. © 2020, Institute of Advanced Scientific Research, Inc.. All rights reserved