Managing evacuations from high-rise and large-capacity buildings in urban environments presents unique challenges. The choice between assembly points and dispersal evacuations can significantly impact the safety and efficiency of the evacuation process.
This discussion explores the benefits and problems associated with these evacuation strategies, particularly in the context of terrorism threats and ensuring the safety of staff and contractors. Additionally, it addresses the importance of phased re-occupancy in large buildings with limited lift capacity using dispersal evacuations.
Assembly Points Evacuations
Benefits
1. Accountability and Head counts
- Assembly points provide a controlled environment for accounting for all occupants, ensuring no one is left behind. This is crucial for large buildings where tracking individuals can be challenging.
2. Emergency Response Coordination
- Designated assembly points allow emergency responders to locate evacuees quickly and provide necessary assistance. It also facilitates efficient resource distribution and coordination of further evacuation if needed.
3. Minimised Chaos
- Pre-determined assembly points can reduce panic and confusion during an evacuation, as occupants know where to go. This orderliness can decrease the risk of injuries and improve evacuation times.
Problems
1. Target for Secondary Attacks
- In the context of terrorism, assembly points can become targets for secondary attacks. A large group gathered in one location presents a high-value target for terrorists, potentially leading to further casualties.
2. Congestion and Accessibility Issues
- Assembly points can become congested, particularly in high-rise buildings where stairwell bottlenecks are common. This congestion can delay the evacuation process and pose significant risks if the building’s integrity is compromised.
3. Visibility to Adversaries
- Fixed assembly points can be easily identified and monitored by adversaries, increasing the risk of targeted attacks on evacuees.
Dispersal Evacuations
Benefits
1. Reduced Target Risk
- Dispersing evacuees in multiple directions to various safe locations reduces the risk of secondary attacks. This strategy spreads potential targets, making it harder for attackers to inflict mass casualties.
2. Flexibility and Speed
- Dispersal evacuations allow for flexible and rapid evacuation routes. In high-rise or large-capacity buildings, this can prevent bottlenecks and reduce overall evacuation time, crucial in emergencies like fires or structural failures.
3. Enhanced Security
- Dispersing occupants to various safe locations can reduce the visibility and predictability of their movements, making it harder for potential adversaries to plan subsequent attacks.
Problems
1. Accountability Challenges
- Dispersal evacuations can make it difficult to account for all individuals, increasing the risk that someone might be left behind or go missing. Ensuring everyone reaches a safe location can be problematic without a reliable tracking system.
2. Coordination Difficulties
- Coordinating emergency response across multiple dispersal points is more complex than managing a single assembly point. Emergency services may face challenges in locating and assisting evacuees spread across different areas.
3. Increased Anxiety and Panic
- Without a clear, unified destination, evacuees may experience higher levels of anxiety and panic, leading to potentially dangerous behaviour and slower evacuation times.
Phased Re-occupancy of Large Buildings
Importance of Phased Re-occupancy
In the aftermath of an evacuation, particularly for large buildings with limited lift capacity, safe and organised re-occupancy is crucial. Phased re-occupancy, done floor by floor, can prevent congestion in the foyer and avoid further terrorism risks.
Key Considerations
1. Lift Capacity Management
- In high-rise buildings, lift capacity is a limiting factor. Phased re-occupancy helps manage this by allowing small groups to re-enter the building sequentially, ensuring lifts are not overwhelmed.
2. Preventing Foyer Congestion
- Avoiding congestion in the foyer is critical to prevent it from becoming a secondary target. A phased approach ensures that only a manageable number of people are in the foyer at any given time.
3. Ensuring Safety
- Phased re-occupancy allows security personnel to inspect each floor for potential threats before allowing occupants to return, ensuring the building is safe.
Effective Communication During Re-occupancy
Effective communication is vital for phased re-occupancy. Secure communication channels ensure that instructions are delivered accurately and promptly to specific groups.
Secure Messaging Apps
Secure messaging apps - like Sentinel PiNG and Chat Channels - allow for real-time, encrypted communication between management and staff. These apps can provide floor-by-floor updates, ensuring each group knows when it is their turn to re-enter the building.
Mass Notification Systems
Mass notification systems can be used to send alerts and instructions to specific groups. These systems ensure that messages reach all intended recipients quickly, reducing confusion and ensuring a smooth re-occupancy process.
Final Thoughts
Choosing between assembly points and dispersal evacuations involves considering various factors, including building type, occupancy, and specific threats like terrorism.
For high-rise and large-capacity buildings in urban areas, a balanced approach incorporating elements of both strategies can maximise safety and efficiency. Phased re-occupancy, facilitated by secure communication channels, ensures a safe and organised return to the building.
Regular reviews and updates to evacuation and re-occupancy plans, coupled with comprehensive training and technological integration, can significantly enhance the resilience of these buildings in emergencies.
Blog Cover Photo by Karl Callwood on Unsplash
