High rise fires

As cities become denser the requirement to build upward toward the sky will continue. Modern building and fire codes must strive to ensure adequate safety legislation grows as rapidly. Fire Services must also be prepared to meet the dynamic and complex situation presented by high rise fires.

An NFPA (National Fire Protection Association) report from August 2016 estimated that the annual average fires and associated losses in US high rise buildings during the 5 year period between 2009-2013 was 14, 500 annually. In this report it listed a high rise as a building of at least 7 storeys above the ground. The report also concluded that most of the fires started on floors no higher than the 6th floor. From this report we can gather how much of an impact these fires have considering the majority of these high rises are also concluded to be residential and thus have a very high human concentration. The fact that the fires start below the 6th floor speaks to building systems most probably being the cause.

If we examine what type of occupancy constitutes a high rise we would see office buildings, apartment buildings, and hotels. Modern building codes have also allowed for a combination of all these occupancies within a single building. The potential for disaster is obvious.

There is a history of tragic fires in high rise occupancies, which became common in densely populated cities by 1900. On March 25, 1911 a fire broke out in Manhattan’s Asch Building occupied by the Triangle Shiftwaist Factory. The fire started on the top three floors of the ten floor building and was found to be caused by the disposal of an unextinguished match or cigarette butt in a waste bin. The building owner had chained the doors to eliminate the staff taking breaks which only left one small elevator as a means of escape. People piled into this elevator as the smoke grew, eventually people started jumping onto the roof of the elevator thereby bending the frame rendering it useless. Fire service ladders could not reach the trapped people; many either died of smoke inhalation or jumped to their deaths. In all 146 people lost their lives in one of the world’s deadliest fires in history. From this fire came wide-ranging legislation which required improved factory safety standards.

February 1, 1974, a fire occurred inside the 25-story Jolema Building in Sao Paulo, Brazil. A short-circuit in a faulty air conditioner on the 11th floor ignited the fire and large amounts of combustible materials, including paper, plastics, electrical equipment and wooden walls and furniture, contributed to the fire spreading rapidly. The death toll was between 179-189. The drama of this fire was that there was now video depicting the tragic events.

In the era of live videos no one can forget the events as depicted on live television of World Trade Centre Towers 1 and 2. In the ensuing fire and collapse 2312 people lost their lives including 343 FDNY Firefighters in their attempt to rescue the trapped. This was the largest loss of life for both civilians and firefighters of any high rise fire in history.

Finally, in very recent memory, was the Address Downtown Hotel fire on New Year’s Eve 2015, although there was no loss of life in this fire the potential risk was certainly evident in this 63 storey building which housed 196 hotel rooms and 626 apartments. The rapid fire spread in this building was attributed to the tower’s external aluminum composite panels.

When examining most high rise fires three points must be examined: 1) the large amount of victims at risk 2) the building/fire codes in place and regulated 3) the resources and capabilities of the fire service.

It has been clearly identified that in high rise fires we are dealing with a large amount of individuals at risk in one place. It is also evident that these individuals are not readily accessible; as buildings get taller people are further away from the building egress point. Pre planning by fire services are a must, understanding not only the buildings themselves but also the building population. For example if the building is full of retired/elderly people you are dealing with a vulnerable population that will add specific challenges. If the building is a hotel it is very likely that individuals will not be familiar with the building and means of egress. Perhaps the most important ideology that must be practised by the fire service is that, unlike a single-family residential dwelling where we remove the victim from the fire, in high rises we must remove the fire from the victim. Most victims in any fire are killed by toxic smoke and gases thus the fire service must practice an approach of sheltering in place. This means that occupants stay in their units (unless directly affected by the fire) and firefighters extinguish the fire rapidly and ventilate the building. This will be further explained as far as achieving tactical priorities for fire services.

The second discussion point, and perhaps the most important, are proper building codes and fire codes. If one looks at legislated life safety codes they almost read as a holy book, everything in them has become law because of thousands of lives being lost. The history of life safety codes have always been reactive, laws being formulated after disasters. In high rise buildings a lack of codes inevitably cause for cheaper construction thus lack of fire protection systems and combustible construction, a combined recipe for disaster. It has to be noted that life safety codes cannot be “borrowed” from another Country or jurisdiction; in order to be enforceable they must be legislated within their own Country. Codes also have to not only deal with current construction but must also reflect existing construction and be retroactive in nature. Insufficient life safety codes have historically been the cause of ignition and the cause of fire spread, thus directly related to high rise deaths.

Finally we must look at fire service response to high rise fires, the required tactical priorities, and required resources in order to mitigate the emergency. As previously described the mentality of responding officers must be that they will shelter in place and remove the fire from the victims. This not only means rapidly getting to the source of the fire, it means coordinating ventilation of the smoke and products of combustion out of the building. When we speak of resources we are initially speaking of setting up an offensive attack which means human resources and not apparatus resource. This means we require plenty of firefighters inside the building to coordinate an attack, and that they will rely on fire protection systems to aid them in this attack. Let’s start by examining the role of the first arriving apparatus, where the first arriving officer will provide a thorough on scene report which will provide the incoming apparatus, and in particular their officers, a plan to form a mental picture and thus size up the situation. The first in Officer will state the strategy as offensive and enter the structure with either 2 or 3 firefighters (depending on staffing). The driver will then provide for initial accountability and connect the pumper to the fire department connection (standpipe and sprinklers). In a properly, legislated, code enforced building, the elevators will automatically ground, the officer in command will verify the annunciator panel for location of fire and announce by radio that information. He/she will then get building keys and secure the firefighter rated elevator and proceed 2 floors below the fire floor to stage. One firefighter will remain in control of the elevator and return to the ground to pick up a subsequent crew and additional equipment. The initial crew with the commanding officer will walk the floor below the fire floor to become familiar with the layout. Command will be passed to an incoming Chief as soon as they are on scene. The 2nd in apparatus will send a crew to join the attack crew and one member will make an announcement on the building communication system that will reinforce the shelter in place strategy and announce that fire crews are dealing with the alarm ( this announcement is to be repeated 3 times). The 3rd and 4th in trucks will be in charge of ventilation and controlling the stairwells. They will pump fresh air into the stairwells thus pressurizing them and making them a safe area of refuge and means of egress for firefighters and if required residence.

It is very evident that firefighter resources required in a high rise fire are extensive, which in the described requirements there is no mention made of firefighter fatigue and the need to relieve the working crews which would require at least 2 times what has already been allocated. Some additional points that would be discussed in this specific training would be how the described tasks would be carried out, outside agencies required, the incident command structure and decision tree, safe and effective placement of vehicles, and a phenomenon known as the stack effect in high rise building. The stack effect refers to the natural movement of air in a high rise building. This effect depends on 5 factors: 1. the overall height of the building, 2. the interior temperature, 3. Exterior temperature, 4. how well the building is sealed to the exterior, 5. how well the building is sealed between floors. Therefore this effect means that in colder climates the smoke will typically vent to the exterior on the upper floors and push inward on the lower floors. In extremely hot climates the opposite would be true. The centre few floors of the building are considered the neutral plane where smoke neither pushes out or in. This phenomenon is one of many that are unique to high rise fires and one of the considerations that must be observed by responding fire services.

There is a long history of high rise tragedies; even though modern building codes have helped mitigate some of the causes of these fires, human behavior and complacency are always present. Fire services must be prepared for the inevitable, proper fire strategies deployed within the first several minutes of a high rise emergency can make the difference in the lives of hundreds.

For more information, go to www.firewise.ca