Fire Suppression in Crowded Dining and Entertainment Venues

Fire is one of humanity's most powerful tools, yet despite technological advancements, it will always pose a threat to people and the environment they inhabit.

The conditions created during the initial stages of a fire are particularly dangerous for humans, while in the later stages, the fire becomes more threatening to the structure itself. For people, a fire becomes perilous when it occurs in an environment that makes it difficult for the population to escape to safety before conditions reach a critical (unsurvivable) point. Statistics show that most fires occur in residential buildings, but a significant number of incidents with a large number of casualties occur in buildings where large numbers of people gather temporarily, such as busy dining and entertainment venues.

The development of a fire is described by the mathematical formula Q=a*t^2, where Q is the released energy (heat), a is the growth coefficient [kW/s], and t is the time from the start of the fire. From this formula, it is clear that the development of a fire in a space largely depends on the available combustible material and the time the fire is allowed to grow without being detected. Major fires in entertainment venues (such as the fire at The Station nightclub in West Warwick, Rhode Island in 2003, which resulted in 100 deaths and 230 injuries) often start from the use of fireworks by non-certified pyrotechnicians or electrical short circuits, which then spread rapidly due to the use of flammable insulation materials and remain uncontrolled due to the absence of suppression systems.

The Importance of Fire Detection and Suppression in Dining and Entertainment Venues

Greek fire safety legislation, through Presidential Decree 41/2018, requires the presence of a fire detection system in venues with a capacity of more than 250 people or in spaces where the main use spans three floors or balconies. The presence of a well-programmed and maintained fire detection system offers multiple benefits:

• Reduction of response time by venue staff and the fire department: Available literature and existing legislation highlight the need for an organized evacuation plan in the event of a fire, but timely notification of the authorities is essential to execute planned actions before the fire reaches an uncontrollable point. At the same time, a suitable fire detection system will minimize false alarms and have the necessary cause-and-effect functions to operate ventilation systems, curtains, or smoke control systems, as well as fire suppression valves.
• Timely notification of the public about the existence of fire and the need to evacuate the premises: According to the Egress Time-Line Model (ETLM), the Required Safe Egress Time (RSET) is defined as the time needed from the start of the fire, the moment of its detection, until the last person exits the space. According to the model, timely detection of the fire reduces RSET while increasing the Available Safe Egress Time (ASET), providing a larger safety margin for evacuating the building.
• Clear communication to the public about the emergency situation: Studies conducted on fires in crowded public gathering spaces highlighted the need for clear communication to the public about the fire, not just earlier notification. According to the Affiliation Model defined by Jonathan Sime in 1984, people, when faced with danger, tend to seek safety in familiar situations. Additionally, it was found that groups of people tend to react more slowly to ambiguous danger signals than individuals, while Latane & Darley believe that people in groups tend to underestimate the risk and overestimate their ability to handle a fire. Based on the above, the need for a fire alarm system that clearly informs the public is evident, reducing the Recognition Time of the ETLM model. It is indicative that the legislator in P.D. 41/2018 recognizes this need and requires the presence of a public address system certified under EN 54-16 and EN 54-24 in public gathering spaces with a capacity of over 1500 people.

Fire Suppression with Sprinklers: Essential Protection

The fire at The Station was a turning point in American history. This incident is both the deadliest accident caused by fireworks and the fourth deadliest fire in an entertainment venue, leading to multiple changes in U.S. fire safety legislation. Indicatively, the adoption of additional escape exits in NFPA 101 "National Safety Code" and the requirement for suppression systems (sprinklers) in all venues with a capacity of more than 100 people were implemented.

The presence of suppression systems, according to American practice, initially limits the energy released during a fire through the use of water from sprinkler systems. The water droplets from the sprinklers cool the solid fuel and the surrounding gas environment while simultaneously altering the pyrolysis rate of the fuel. Additionally, they change the density and temperature of the released smoke as well as its movement speed. The result of these complex physical interactions is the reduction of the fire and smoke growth rate, the limitation of the flashover risk, and the extension of the available RSET. According to the NFPA, the use of sprinklers reduces fire-related deaths and injuries by 90% and 32%, respectively.

The Necessity of a Fire Safety System

Dining and entertainment venues represent a unique category of buildings: they are commercial spaces operating primarily for profit, characterized by high population density of people temporarily in the space, often in a state of limited awareness (darkness, loud noise, alcohol influence). In these spaces, the occurrence of a fire is a high-risk situation that unfortunately leads to human casualties. The presence of a robust fire detection and suppression system serves multiple purposes: it limits the extent of the danger, ensures human safety, and reduces the material damage that the building installation may suffer.

Bibliography:

1: J. Strick (2014). Development of Safety Measures for Nightclubs, Lund University, Division of Fire Safety Engineering http://lup.lub.lu.se/student-papers/record/4522713

2: J.D. Sime (1983). Affiliative Behaviour during escape to building exits, Journal of Environmental Psychology https://doi.org/10.1016/S0272-4944(83)80019-X

1. Latane, B., & Darley, J. M. (1968). Group inhibition of bystander intervention in emergencies. Journal of Personality and Social Psychology, 10(3), 215–221. https://doi.org/10.1037/h0026570
2. Tucker McGree (2024). U.S Experience with Sprinklers, NFPA https://www.nfpa.org/education-and-research/research/nfpa-research/fire-...
3. P.D. 41/2018

Author:

Athanasios Eleftheroudis, Technical Studies Manager at Olympia Electronics