Smoke contamination of balconies due to a channelled spill plume at a lower level in an atrium might occur during a fire and could affect occupant safety during an evacuation. Previous experimental work has investigated the extent of smoke contamination, and this work describes a numerical modelling comparison of the experiments using the Fire Dynamics Simulator (FDS) computational fluid dynamics programme. Temperature, severity and height of smoke contamination are selected as the key parameters for comparison. The predictions of severity and height of smoke contamination are generally similar to the experimental results using a 'most severe point assessment of smoke contamination' assessment method. Although predicted temperatures are slightly lower than experimental values, FDS temperature slice files can be used at the most severe smoke contaminated point using a 10 ˚C temperature rise. This 10 ˚C threshold matches the criterion proposed in the previous experimental research. On the basis of the comparisons for the height of smoke contamination, the simulation results generally match a previously proposed equation for the height of smoke contamination above a balcony spill plume.

Empirical equations determining heat transfer between a smoke layer and a sprinkler spray have been assessed by using data from several experiments available in the literature. The comparison of the heat loss and temperature of the smoke layer under sprinkler spray shows that the equations developed by Williams for 15 mm pendent conventional sprinklers agree reasonably well with the experimental results. Equations from Spearpoint et al. (Spearpoint MJ, Williams C and Morgan HP. Engineering relationships for calculating the heat transfer from a horizontally-moving Buoyant smoke layer to a sprinkler spray, Fire Research Station, Borehamwood, Herts, UK, 1993 (unpublished)) perform fairly well compared to upright sprinkler experiments especially for a spray sprinkler case but need more validation due to the lack of experimental data. Predictions from the equation given by Heselden are close to the values for a pendent conventional sprinkler with a depth below ceiling less than 0.3 m but values are lower than those given by Williams (Williams C. The Downward Movement of Smoke due to a Sprinkler Spray,