Hostile Vehicle Mitigation (HVM) measures are widely used to protect areas and spaces where a high volume of people are present. Recently, a new threat has been identified as some security barriers carry their own risks, particularly the potential for projectile hazards in the event of a high-energy impact.
The Projectile Risk Explained
When a vehicle collides with an HVM barrier at high speed, the force of the impact can cause the barrier material, especially concrete, to shatter and turn into high-velocity projectiles. These projectiles can travel considerable distances, posing a severe threat to bystanders and crowds in the vicinity.
The severity of the projectile risk depends on several factors, including:
- Vehicle Speed: The higher the speed of the vehicle at impact, the greater the force imparted on the barrier, increasing the likelihood and intensity of projectile formation.
- Vehicle Mass: Heavier vehicles, such as trucks or buses, carry more kinetic energy, leading to more severe barrier fragmentation and projectile hazards.
- Barrier Design: The type of barrier, its composition, and its construction can influence the way it fractures and the characteristics of the resulting projectiles.
Mitigating the Projectile Risk
To address the HVM projectile risk, several strategies can be employed:
- Barrier Selection: Choosing barriers designed to minimize fragmentation and projectile formation upon impact can significantly reduce the hazard. Some barrier types, such as cable barriers or energy-absorbing systems, are specifically engineered to mitigate projectile risks.
- Standoff Distance: Increasing the distance between the barrier and the protected area can provide more time and space for projectiles to dissipate their energy, reducing the threat to bystanders.
- Site Planning: Careful site planning can minimize the exposure of pedestrian areas and crowds to potential projectile trajectories, further reducing the risk.
While HVM measures are crucial for protecting against vehicle-ramming attacks, it is essential to consider and mitigate the associated projectile risk. By employing appropriate barrier systems, implementing standoff distances, and carefully considering every site individually, the safety of pedestrians and crowds in public spaces can be significantly enhanced.