Extensive exposure to smoke remains one of the primary causes of fire-related fatalities, especially in high-rise buildings. In the 1981 Toronto Hotel Fire, a fire began on the 2nd floor of the 23-story building. The fire was contained to the room of origin, but the smoke spread was significant. Six fatalities occurred in the stairwells and upper floors of the hotel as a result of smoke spreading through the elevators, stairwells and vertical service shafts. Although many other fire protection features have been added to building and fire safety codes over the years, firestop and maintaining fire barriers remain one of the primary methods of controlling the spread of smoke and fire in high-rise buildings.
Three Reasons Firestopping Is Important in a High-Rise Building
1. Vertical Smoke Spread – Fires in high-rise buildings generate large quantities of smoke that tend to spread vertically throughout the building, even if the fire is contained to only one room. A complex series of pipes, ducts, cables, and conduit run vertically through high-rise buildings in order to provide utility services to the upper floors. These vertical utilities create numerous openings and gaps that allow smoke to travel and spread to higher floors. Addressing these penetrations by properly installing firestop, maintains the fire-ratings of horizontal fire barriers between floors. This delays vertical smoke spread and reduces the risk of smoke-related deaths in the upper floors of the building.
2. Longer Evacuation Times – The potential for crowding and slow movement in egress routes (stairways and corridors) increases in high-rise buildings. This is a result of a higher density of occupants in the facility combined with greater distance to exit the building. The longer it takes for an occupant to exit the building, the higher their chance of smoke exposure. For this reason, it’s important that fire walls protecting the routes of egress remain code-compliant and any penetrations in these barriers are firestopped without delay. This will prevent fire and smoke exposure to egress areas and ensure there is sufficient evacuation time before smoke reaches lethal levels.
3. Fire Department Access & Increased Fuel Load – Firefighter rescue from the exterior of a high-rise building is limited to the lower 6 or 7 floors of a building. When a fire is above the reach of ladders, firefighters must move vertically inside the building to launch an interior attack, while occupants are exiting using the same stairwells. This can result in delays in attacking the fire and longer burn times.In addition to slower attack times, fire spreads more quickly in a high-rise building due to the greater density of fuel within the building footprint. A higher density of occupants, furniture, and belongings in addition to combustible building materials all contribute to the increased fuel load.
For the above reasons, NFPA code requires that open penetrations in fire barriers be firestopped “without delay”. With the increased risk of damage and smoke-related fatalities in a high-rise building fire, it’s more important than ever to remain aware of the condition of their fire barriers. The need for passive fire and smoke control, including the proper protection for penetrations in fire barriers, is as critical now as it was when high-rise building construction was first introduced. And buildings continue to be built taller than ever.
Establishing a Firestop Maintenance Plan Can Help
Having a plan for fire barrier maintenance is a proactive way to maintain the integrity of fire barriers in a high-rise building. When fire barriers are looked at on a regular schedule, problems can be addressed on an as needed basis. This ensures that the fire-resistance ratings of your fire barriers are maintained and will allow for safe egress of building occupants and minimize damages in the event of a fire.
If your fire barriers haven’t been maintained for a while or if you aren’t sure of their condition, a firestop maintenance plan allows you to effectively tackle the daunting task of surveying and firestopping the entire building. Breaking the work up by firestopping a certain number of floors on a monthly or quarterly basis, can help organize the effort and allow you to spread out the work and cost over time.
PREVENT Life Safety can help! If you’d like help setting up a firestop maintenance plan or have barriers in your building that need to be addressed, call us at 877-392-6074 or request free quote.