SR430 Preparing the foundation for risk-informed fire safety design (2019)

This study report provides a summary of a research project that aimed to identify uncertainties in the current parameters used to validate fire safety designs using the Verification Method C/VM2. The New Zealand Building Code and C/VM2 were analysed to identify the engineering parameters that are used in various calculations for fire safety modelling.

It is proposed that the uncertainties in these parameters can be characterised using statistical probability density functions (where data is available) giving a range of potential outcomes in order to form the basis of a risk-informed fire safety design. A wide range of parameters were identified, and a literature review undertaken to determine whether the parameters have been investigated previously and have statistical distributions available or not. The literature review covered parameters that fell into three main areas: those required for calculating the available safe egress time (ASET), the tenability limits for occupants and the required safe egress time (RSET). The main parameters included fire growth rate, heat release rate, fire load energy density, species production, ventilation conditions and movement times.

Further work will be required to identify statistical distributions for parameters not yet classified at this time. That said, probably of greater importance would be a sensitivity analysis to determine which of these identified parameters have the greatest influence on the outcome of engineering analyses. In this way, research can be focused on the key parameters required and the greatest research impact can be targeted.

See the BRANZ Research Now for a short and accessible summary of this report