It wasn’t long ago that professionals in the fire safety community saw evacuee response as a more or less random event. It was thought that occupants of the building, gripped by fear, would dash for the closest exit, regardless of the actual conditions around them.
Fortunately, we have a more nuanced understanding of occupant response today, says Steven Gwynne, PhD., a senior research officer with the National Research Council of Canada who was featured speaker at the SFPE North America Conference & Expo: Accent in Fire Protection Engineering. We now understand that evacuees build a mental picture of the situation — the level of perceived risk, the nature of the threat, the reaction of fellow occupants — that steers them toward a particular decision.
And because of that development, Gwynne says, fire safety experts have increasingly relied on models to better understand the expected response of evacuees. This allows them to quantify potential outcomes — specifically, how long it will take occupants to exit the building — based on a variety of different floor plans and other inputs.
But the problem with traditional models is that they’re simply not flexible; they can’t account for a range of different scenarios that have to be considered when designing a building, implementing safety guidelines, or responding to a fire.
According to Gwynne, that’s why computer simulations can play such an important role in addressing fire safety challenges. Engineers, safety managers, and fire chiefs can not only examine hypothetical events in greater detail, but quantify results based on a multitude of variables.
A computer simulation based on sound assumptions is a vital tool in alleviating congestion in larger building fires and ensuring that first responders make informed decisions.
More Accurate Models
The value of software simulations can impact the entire lifecycle of a building, explains Gwynne, who has studied evacuation dynamics for 20 years. The following are just a few of the potential applications where he says a computerized model can play a useful role.
Creating an Optimal Design
Computer simulations allow architects and engineers to assess the impact of various floor plans and notification systems (including bell and/or voice alarms) when creating their designs. They can also quantify the effect of different evacuation procedures — total evacuation, phased evacuation, etc. — to assess their safety impact. The simulation enables them to determine, with greater accuracy, the time it takes to evacuate a building based on each of these factors.
Adjusting Safety Plans
By utilizing software models, a building’s safety manager can create a more effective plan and, crucially, modify that plan as circumstances evolve. For example, should certain floors increase their occupancy over time, the safety manager can use a simulation to predict the effectiveness of different evacuation routes.
Guiding First Responders
Simulations are indispensable training tools that allow firefighters to visualize the impact of different interventions based on a variety of fire conditions and population scenarios. As a result, they’re able to develop response plans that provide for faster evacuation times.
A Cost-Effective Solution
By enabling fire experts to gain insights before, during and after designs are employed in the field, computer simulation tools can play a key role in helping to save lives, Gwynne says.
Electronic simulations are certainly not a panacea for the many challenges that a fire presents; indeed their effectiveness depends on the quality of the assumptions that one feeds into the model. But when used appropriately, they enable designers, managers and responders perform their respective roles with great precision and effectiveness. They also represent a highly cost-effective tool, given the cost and risk associated with experimental fires.
Simulation software is becoming more widely used by engineers and researchers, and the cost of these programs has lowered enough that many fire departments and fire safety managers now have it within their budget to purchase a license. If that’s not the case, you might consider contracting with an engineering or research organizations that can run simulations for you.
Considering the benefit they provide to professionals across the fire safety spectrum, it’s a tool that needs to be more universally embraced.