Aspects of operating PPV in ministorage fires

Abstract

‘Positive ventilation attack’, a common firefighting technique in a room fire, is supposed to give better visibility and to lower the air temperature while via operating the positive pressure ventilator (PPV). However, about half of the cases applying PPV were found not to work as expected. This was experienced while fighting against big ventilation-controlled room fires.

A big fire broke out in an old industrial building with mini-storage facilities in Hong Kong, 2016. Post-flashover fire lasted for 108 hours with two firefighters killed. Many questions requiring research effort to answer were raised about this big long fire by different parties. Whether air supply by PPV would increase burning rate to give a big ‘ventilation-controlled’ fire is the most difficult question to answer.

The scientific basis discussing the effect of PPV on a big room fire is reported in this paper. Systematic research has to be carried out for addressing the above question scientifically with full-scale burning tests. It is difficult to compile an investigation report within a short time.