20 Oct Protecting cinemas & places of public assembly
Across the world there have been many examples of fires in public assembly buildings which have resulted in the tragic loss of life. Fortunately, lessons learned from past events have led to the creation and updating of life safety codes to address these deadly types of fires. The potential for loss of life in a public assembly fire is directly related to the number of people who are threatened. Success in mitigating the effects of these fires depends on awareness of the special problems that are associated with public assembly buildings writes James F Daniels, Fire Safety Manager, Warringtonfire.
On november 28, 1942 492 people died in the Cocoanut Grove, Boston, USA, nightclub fire where panicked occupants were trapped by locked exits and jammed revolving doors. It was estimated that there were more than 1,000 patrons in the club at the time of the fire, which had a legal occupancy capacity of
460 people.
The resulting life safety code that originated from this fire initiated changes to the fire safety requirements in public assembly buildings including emergency lighting, exit lights, occupant capacity limits and outward-opening exit doors.
There have also been tragic fires in cinemas across the world. The Glen Cinema disaster in Paisley, Scotland, on 31st December 1929 which was caused by a smoking film canister, killed 70 filmgoers and is considered one of Scotland’s worst human disasters. A more modern example was the Uphaar Cinema fire in Delhi on 13th June 1997, which was one of the worst fire tragedies in recent Indian history leaving 59 dead and over a 100 seriously injured.
Safety concerns
Cinemas, often multi-screen venues, are commonly found in large, crowded, buildings of multiple use such as a malls or leisure centres or more recently in an airport complex. The large number of people present represents a significant potential for loss of life in the event of a fire. It therefore requires the highest standards of design and management to ensure that risks are anticipated and covered by the best possible systems for life safety and property protection. Assuming the original design is well coordinated, and the fire strategy is robust, the one key factor that needs to be present, if disaster is to be averted, is a high standard of fire safety management.
As highlighted above, often the one common element in multi-fatality fires is the failure of the occupants to take the right action when fire is discovered, or when the alarm is raised. Only effective management, combined with adequate and appropriate training, can ensure that the correct actions are likely to be taken by staff members to assist members of the public to safely leave the building. As escapees are likely to be familiar with the primary entry routes only and may have limited knowledge of the venue layout, it is therefore important that the alternative exits are correctly signed, and that staff assistance is available to guide people to the exits.
Many shopping malls and airports in the region not only provide a complete shopping and leisure experience, but also provide direct interfaces to hotels, apartments and transportation infrastructure. The evacuation strategy for the whole building must consider all potential users, including those who are awake and familiar with the building, and those likely to be asleep and unfamiliar with the building layout.
The UAE Fire & Life Safety Code classifies cinemas as an Assembly occupancy Group A and the International Code Council classification is A-1 which covers cinemas, theatres and the performing arts.
Construction and design
Construction and design of a building should intrinsically consider the life safety of occupants, but often it does not. For example, nightclubs and restaurants might be located on the top floors of high-rise buildings. This location can delay firefighters from arriving and attacking a fire in a timely manner. If delayed, they cannot assist in initial rescue or evacuation efforts.
A public assembly building might consist of large, unbroken areas that allow a fire/smoke to spread quickly. On the other hand, a maze-like configuration can confuse people who are disoriented by smoke and trying to locate the route through which they entered the building.
Firefighters might find that building access/egress is limited because of building renovations, which can include false fronts and windowless design. Some buildings have been converted from other occupancies to leisure, including cinemas, and firefighters who are unaware of this change in building occupancy could be confronted with a serious life hazard problem if they are unaware of the change of use.
A person who is unfamiliar with a building most likely will not react according to a prescribed evacuation plan unless directed to do so by a person in authority. Under emergency conditions, this direction might not be given, or the person might not understand the message. This leads to individuals reacting in a way that they believe will best safeguard themselves, possibly causing evacuation problems for firefighters.
A building’s heating, ventilation and air-conditioning (HVAC) system can spread fire and smoke. Knowledge and control of these systems by the fire department might assist firefighting operations if it is deemed beneficial to utilise these systems to ventilate smoke from the building. If this is not possible, these systems should be shut down immediately to prevent the spread of fire and smoke.
Furnishings and finishes
Although an official can diligently inspect a building during construction for code compliance, furnishings that are added afterwards can contribute to a fast-burning fire. A management concern is the aesthetic effect that is created by furnishings; rarely is attention paid to the fire resistance of a material that is selected for their premises. The recent move to VIP cinema experiences may have an impact on the variety of furnishings that could increase the fire load in such venues.
Seasonal motifs, including Halloween, Easter and Christmas decorations and promotional events at cinemas, can pose a potential threat. Live evergreen trees, although beautiful, dry out quickly. When ignited, they release a tremendous amount of heat. Loosely hanging banners or crepe paper can ignite easily.
Decorative combustible furnishings will let fire spread at such a rate that the occupants might have little time to escape. At the Beverly Hills Supper Club in Southgate, Kentucky, USA, in 1977, untreated, decorative materials contributed to the rapid spread of fire. The aforementioned Cocoanut Grove fire was fed by flammable decorations.
The MGM Grand hotel and casino fire, in Las Vegas in 1980, started in a non-sprinkler protected restaurant/deli that wasn’t open for business at the time. The adjacent casino covered an area of 150 feet x 450 feet. It took only six minutes from the time of the discovery of the fire for the total casino area to become involved in the fire. It was estimated that the fire travelled at a rate of 19 feet per second making operational firefighting extremely challenging.
In February 2003, a deadly fire occurred in West Warwick, Rhode Island, USA, at the Station nightclub. The fire was started by a band’s pyrotechnic display, which ignited foam decorations and wood panelling. Patrons first recognised danger 24 seconds after ignition, and the bulk of the crowd began to evacuate around the time that the band stopped playing (about 30 seconds after ignition). The heat and smoke detection system activated 41 seconds after the fire started. Approximately 90 seconds into the fire, about two-thirds of the occupants attempted to leave via the main entrance; a crowd crush occurred at that location, which almost entirely disrupted the flow of the evacuation through the front exit. Flames were observed breaking through the roof less than five minutes after the fire started.
Measurements in a fire test which was conducted by the National Institute of Standards and Technology in a mock-up of the Station nightclub’s platform and dance floor produced temperatures, heat fluxes and combustion gases that were well in excess of accepted survivability limits within 90 seconds. The tremendous speed of this fire, which was captured on film, shows how little time firefighters had to even attempt to make a difference.
The factors that affected this fire were the use of pyrotechnics and the decorative foam and wood panelling, which easily ignited, causing the rapid-fire spread.
Occupancy
The number, and placement, of exit doors in cinemas and public assembly buildings is based on the number of people that can be expected to occupy a building. However, public assembly buildings have the potential for overcrowding; this can be a common occurrence in popular nightclubs during special events, also, the number of multi-screen cinemas offering multiple viewing choices to customers brings the challenge of catering for a variety of age groups and family groups, etc. all having the potential to react differently in an evacuation scenario. During an emergency evacuation, and where overcrowding exists, exit doors can become congested with people, restricting egress. The inability to leave a building when confronted with a fire or smoky conditions can lead to an uncoordinated evacuation.
Exits
Cinemas in places of assembly might have only a single entrance which is familiar to patrons, which hinders a rapid and orderly exit. An adequate number of properly marked and unobstructed exits is extremely important for a robust fire strategy. Tables, curtains, large planters and other decorative schemes may compromise an exit or egress route. Unfortunately, limited perception of danger is realised by management, or by most occupants, through these actions. The problem is often down to the general apathy toward fires. Most people feel that fires happen to other people, or they have never experienced the devastation, human tragedy and loss of business that can result from a fire.
The availability of all exit doors should be checked prior to the arrival of the public to a cinema and other assembly buildings. Locked exits not only cut down the number of exits that are available but also can cause deadly delays. A fleeing occupant who finds a locked exit door needs to locate another exit. A firefighter might be endangered by relying on an exit as a secondary means of egress, only to find the door locked. During the Cocoanut Grove nightclub fire, panicked occupants were trapped by locked exits and jammed revolving doors.
Evacuation
Some public assembly buildings are easier to evacuate than others. Human behaviour can play a key factor in the success of an evacuation and building management teams should understand the likely behavior of different building user groups.
A bingo hall can have its challenges as patrons don’t want to be disturbed unless confronted with conditions that they consider life-threatening. People who are told to leave a cinema may want a refund before exiting, adding confusion and delay. The ease of evacuating a restaurant depends on whether the patrons already ate their meal. If so, they leave happily; if not, they might resist. The move towards providing food and beverages in cinemas now as part of the VIP experience can add an additional tier of human behaviour in the event of an emergency.
Strategic considerations
Overcrowding will compound evacuation problems. There might be many occupants who are unfamiliar with the building hurrying to escape, but in the wrong direction. Lighting might be dimmed for an aesthetic effect. Smoke might further cut visibility. It isn’t always possible to determine whether everyone has been evacuated or whether some individuals are still trapped within a building.
Familiarisation with suppression systems lets firefighters know what building protective systems can assist them. When arriving on the scene of a sprinklered building, they need to be prepared to support the sprinklers to ensure an adequate flow of water; stretch hose lines to these systems and pressurise them if the system has been activated.
A decision must be made on whether firefighters should be committed to fight the fire or assist in evacuation. A direct attack to control the fire often is the best method for saving lives. Coordination is needed to ensure that firefighting efforts don’t endanger occupants who are trapped or evacuating the building. Immediate ventilation can often be a viable strategy for saving lives. The removal of smoke and gases, although initially accelerating the fire, might permit an effective evacuation and fire attack.
Long hose line stretches must be anticipated, and those that are stretched must not interfere with people who are evacuating. Hose lines can’t be stretched into the building via doorways that are being utilised for evacuation; they would cause confusion and hazards for the escaping occupants. Firefighters must use another location or wait until the evacuation is completed.
Identifying problems
The major method to deal with public assembly fires is thorough preplanning, code enactment and code enforcement. During these processes, potential problems can be found and resolved. Hiring experienced Fire Engineers as early as possible during the planning stages of a project is a good way to ensure this isn’t missed.
Life safety systems must include installation of fire protective systems to alert occupants and control and/or extinguish an incipient fire. Within the UAE Fire Code there is a requirement to provide fire rating for the separation between theatres, cinemas or concert halls from other parts of the building. The level of separation required from other parts of the same building, which is of a different purpose group, by compartment walls and floors having a fire resistance of at least 2-hours. If the building is protected by an automatic sprinkler system, the fire resistance rating of the compartment walls or floors can be reduced to 1-hour.
The management team of a cinema complex should develop robust emergency response plans which are rehearsed by all staff members. An on-going process of fire risk assessment should highlight any issues that require immediate attention to reduce the risk of fire occurring. Robust maintenance schedules should be in place for the installed fire safety systems with regular fire drills carried out to ensure the evacuation plans are robust in the unlikely event they need to be implemented.