DESIGNERS SHOULD pay more attention to the type of people who will be housed in a building when considering evacuation procedures, Mott MacDonald said this week.
Mott has developed a software system known as STEPS - simulation of transient evacuation and pedestrian movements, andsaid computer modelling of a building's function, the people it houses and how they would escape in different fire disaster scenarios could improve evacuation design and save more lives.
Had such software been available when the World Trade Center towers were built, said Mott, more lives could have been saved after the attack on 11 September.
Mott's software analyses what delays different groups of people leaving, such as children, the elderly and general staff.
'You have to consider the things that stop people evacuating quickly, ' said mechanical associate and fire design expert Steve Logan.
Four behavioural assumptions that cause delays in a crisis are modelled using STEPS.
'People can initially be expected to show disbelief and seek their own confirmation that fire has broken out, ' said Logan.
They can also be kept back by commitment to the task they are completing, such as watching a football match, he explained. 'In Bradford Stadium, people were waiting for the game to start while a fire blazed 15m away.'
People generally herd towards friends, work colleagues and family before escaping, behaviour known as affiliation. If someone is unsure of their surroundings they will seek guidance from permanent building residents.