By analysing the development of a fire, its' interaction with the building and its' occupants, it is possible to free the designer of the building from the normal constraints imposed by compliance with standard guidance.

Until recently fire modelling techniques were prohibitively expensive except for the largest of building projects. Now, thanks to advances in computer processing power and modern software, these techniques can be extremely cost effective.

Computational Fluid Dynamics

Computational Fluid Dynamics (CFD) is a technique which enables the study of the dynamics of fluid flow. Using CFD, a computer model is built that represents building or structure. Fluid flow physics is then applied to this virtual prototype, and the software provides a prediction of the fluid dynamics.

CFD is a sophisticated analysis technique. It not only predicts fluid flow behaviour,
but also the transfer of heat and mass (e.g. convection or diffusion), phase
changes (such as in freezing or boiling) and chemical reactions (such as combustion).

hnla fire engineering utilizes Fire Dynamics Simulator from the National Institute of Standards and Technology (NIST)in the USA. The package uses computational fluid dynamics (CFD) to produce predictions of heat and smoke distribution throughout the area studied. The software is capable of producing a virtual reality presentation of fire conditions.

Fire Evacuation Modelling

Means of escape requirements imposed by standards guidance are based on assumptions which are often invalid.

Fire evacuation modelling can help the building designer and the fire engineer work together.
This cooperative approach produces a building that is able to function more effectively in the fire situation, whilst allowing more freedom in the design process

STEPS
hnla utilises STEPS for evacuation modelling. Developed by Mott MacDonald, STEPS is widely accepted within the fire industry and by approval authorities

Evacuation Modelling Diagram courtesy of Mott MacDonald