The Need for Emergency Planning
Understanding Fire Safety Obstacles
The explosion and ensuing fire at the World Trade Center on February 26, 1993, was the worst bombing in the nation’s history causing between $600 million and $700 million in damages and losses. The nightmare of a similar disaster has become a reality to only a handful of building managers and owners. Two of the most destructive single structure fires in recent United Stales history were the First Interstate Tower in Los Angeles, May 1988, and One Meridian plaza in Philadelphia, February 1991.
These disasters received nationwide attention, but thousands of fires and small emergencies occur each day. Any emergency can result in fatalities, large property losses, costly business interruptions, tenant move-outs, expensive building repairs, plus years of legal action against the owners of the building. Preparing for a disaster, and being more aware of the fire safety obstacles in high rise buildings, can help reduce losses and prevent a small emergency from erupting into a disaster.
Problems Fighting High-rise Fires
High-rise fires produce unique problems. Because of the large numbers of people and the tremendous size of the buildings, the potential for a major incident is greater in these occupancies. Populations of high-rise structures can exceed that of small communities, and evacuating such a large mass of people is a difficult task. An office building emergency could halt the work of multi-million dollar tenants while a residential high-rise fire could destroy hundreds of people’s homes. There is the risk of toxic fumes from burning synthetic material and insulation, like asbestos. Confusing and overwhelming fire control rooms, which are different from building to building, put an additional burden on fire fighters. The most valuable tool any fire fighter can have in a structural fire is knowledge. Knowledge of the structure and its systems empowers the fire department to make clear, competent decisions. With proper information, judgments can be based on accurate, detailed information-not guesswork.
Structural Features
Structural features have a profound impact on fire-fighting tactics. Modern high-rise construction uses a great deal of synthetic material. Fires fueled by synthetic compounds burn quicker and hotter and produce toxic gasses. Additionally, modern construction design tends to hold heat inside where it will intensify quickly. The excessive heat produced in high-rise fires increases the threat to tenants, fire fighters and the systems and structural supports of the building itself. Following are some high-rise building features and their impact on a fire:
- Fire resistive construction and heavy insulation of high-rises will contain heat as the contents of the building burn, intensifying the temperature of the fire and the buildup of smoke inside.
- Synthetic material, used in building construction and building contents burns quicker and creates higher heat and smoke emission rates than fire loads 30 years ago.
- The HVAC system can have serious effects on a fire’s development. Shut down of the air supply has two effects: it will inhibit the development of the fire by decreasing the amount of supplied oxygen, but it will also increase the concentration of toxic gasses due to incomplete combustion.
- Associated with HVAC, fire and heat can spread quickly through ceiling plenums. The fire will be drawn through the ceiling plenum toward the least obstructed air shaft of the HVAC system. This movement contributes to rapid fire growth.
- The HVAC system can also be used by fire fighters to ventilate a burning building. However, without an understanding of the building’s systems, fire fighters often resort to breaking windows. This is a costly, ineffective and dangerous form of ventilation in a high-rise.
- Central-core design, used in many modem high-rises, puts stairwells and building utilities in the center of the building where they are most vulnerable to excessive heat and smoke. This danger has not gone unnoticed. Steps have been taken to protect the central core: stairwells are often pressurized and systems throughout the core are insulated and fire stopped. Unfortunately the destructive forces of fire and heat can reduce or destroy their effectiveness. Contamination of these vital areas restricts occupants and fire fighters of their use.
- Insulation used to fire stop structural steel and penetrating shafts of the building is questionable in its reliability. Fire stop material has not always held up as well in actual fires as it has in controlled testing. The fire stop is affected by many variables; its effectiveness can be reduced during manufacturing, installation or renovation of the building.
- The open floor plan, use of five foot dividers to create multiple work stations, contributes to the rapid growth of a fire. The lack of compartmentalization and the free flow of air will allow a fire to extend and consume the fire load of an entire floor.
These structural concerns weigh heavily on the fire department who rely on the building’s integrity and systems as they move throughout the building. Cooperation between the fire department and building management is necessary to identify and deal with structural features including building systems and the problems they present during an emergency.
Building’s Role in an Emergency
Recently many building owners and managers have realized the importance of developing emergency plans. Planning prepares building personnel for their responsibilities to the fire department. Emergency plans can also be helpful in educating employees of the building’s systems and features. Incorporated in the emergency plan should be tenant evacuation procedures. When an emergency strikes, the fire department’s first concern will be the safety of the tenants. Initial efforts to move tenants to safety will allow the fire department to concentrate more fully on handling the emergency.