Real explosions in domestic structures (Rasbash and Stretch, Struct. Eng 1969;47;403-11) and industrial plants (Howard, Loss Prevention 1972;6;68-73) have been analyzed. Deflagration dynamics are solved for enclosures of volumes of 130-8000 m(3) for vent release overpressures in the range of 0-0.21 bar, and for different inertia of covers over the venting spaces in the range 0-15 kg/m(2). From comparisons of the real explosion data with the modeling of pressure-time behavior during vented gaseous deflagrations according to an earlier lumped parameter theory values of the main parameter, a turbulence factor, chi. are obtained. The results suggest the combustion is highly turbulent for real conditions in domestic structures (turbulence factor chi greater than or equal to 8 with discharge coefficient mu = 0.6) and especially in large-scale enclosures such as a plant, with internal obstacles (turbulence factor chi greater than or equal to 17). On the basis of the devised effective turbulence factors (the ratio chi/mu) the design procedures for avoiding the development of-excessive overpressures during deflagrations, in both domestic and industrial plant, can be improved. (C) 1999 Elsevier Science Ltd. All rights reserved.