What is Hostile Vehicle Mitigation?
Hostile Vehicle Mitigation (HVM) is a protective security discipline focussing on reducing risks associated with vehicle borne threats posed by terrorists and criminals. HVM is the delivery of measures that are informed by the threat and how it manifests itself, the multiple consequences of an attack, the vulnerability of a given location and the needs of the enterprise requiring protection. The basis of HVM are security risk assessments, security planning, and design and the deployment of risk-based measures. (NPSA)
In practical terms, HVM is not simply about installing barriers. It combines planning, people, processes and, where justified by the risk, physical measures to reduce vulnerability to vehicle-borne threats.
How Hostile Vehicle Mitigation has evolved
Physical HVM measures have evolved, and now come in a wide variety of shapes, sizes, purposes and functionality. From specifically designed and installed permanent fixtures, such as bollards, street furniture (planters, bike racks, benches etc), vehicle security barriers at entrance points to locations where the identified risk and operational requirement justify permanent protection. Permanent HVM can also include adapted hard landscape features, such as significant level changes, and with a little imagination HVM may be disguised inside architectural features in a street scene.
Temporary HVM solutions provide another option where permanent measures are neither necessary nor operationally appropriate, including some sporting events, markets and festivals. Modern systems can offer tested performance alongside pedestrian permeability, authorised vehicle access and efficient deployment and removal. These solutions are more easily deployed and removed, are more lightweight and offer practical benefits, such as lower transportation costs, reusability, and fewer personnel needed to install them.
The video below demonstrates the manoeuvrability of the RB50, a surface-mounted, modular HVM system with IWA 14-1 impact ratings.
There are more mundane, but untested solutions – such as using an HGV to block off a road or filling a skip with water or building rubble to deter a vehicle-borne attack. These however, come with their own risks. Using a vehicle to block off a road immediately turns that vehicle into a weapon. It is laden with fuel, which may explode if targeted by a hostile vehicle ramming it, and so cause death or injury to anyone in the near vicinity. A vehicle must have a driver to get to its location, and who must remain with it at all times – in case it needs to be moved quickly. As we saw in a couple of the European terrorist attacks (Berlin 2016 and Stockholm 2017), the drivers of the HGVs were attacked, one sadly died, and their vehicle stolen to be used as a weapon.
The HVM market now offers a much broader range of tested and rated solutions. These include temporary surface-mounted systems, removable and semi-permanent measures, and permanent solutions, allowing the specification to be matched more closely to risk, accessibility, operational requirements and the surrounding environment.”
For temporary deployments, effective HVM is not achieved simply by placing physical obstacles around an event. Any measures should form part of a wider protective security approach that considers the identified risk alongside pedestrian movement, accessibility, authorised vehicle access, traffic management and event operations.
HVM decisions should be informed by an appropriate assessment of threat, vulnerability, potential consequences and operational requirements. Where specialist HVM is justified, this enables measures to be selected proportionately, with residual risk understood rather than assuming that more physical security automatically means better protection.
“HVM measures are the integrated deployment of security processes, procedures and physical obstructions to counter vehicle borne threats. They typically include; deterrent communications, security awareness, incident response planning and training, operational security, traffic management and the deployment of physical obstructions such as vehicle security barriers and traffic calming measures.” (NPSA)
This distinction is important: HVM is protective security, not simply traffic management or a road closure. Traffic management may support an HVM strategy, but physical products and operational processes need to work together as part of the wider security plan.
Understanding HVM Testing and Standards
All of the temporary HVM products that our specialist teams deploy are rated solutions. This means that each product is a ‘Rated Vehicle Security Barrier’ which has undergone formal vehicle impact testing. An impact rating provides defined information about how a VSB performed under specified test conditions. It should therefore inform, rather than replace, a risk-led specification.
In 2023 a new global standard was introduced – ISO 22343-1 – which became the current international standard for new vehicle impact testing, superseding:
- ISO IWA 14-1:2013
- BSI PAS 68:2013
- ASTM F2656/F2656M – 20
For VSBs tested on 1st March 2024 onwards, NPSA will only recognise those with an ISO 22343-1 performance rating. However, VSBs tested before this, to withdrawn standards, will still be considered for entry into NPSA’s Catalogue of Security Equipment.
Tests are conducted on a variety of vehicle types and weights at varying speeds and impact angles, to measure the ‘stopping power’ of the VSB, and the depth of penetration and the amount of vehicle debris that results from the crash test.
The new ISO standard ratings are displayed like this:
Guidance notes for the new ISO 22343-1 Standard can be found here.
However, it should be noted that testing conditions (weather, time of day) will affect the outcome of tests, to some degree or another. When considering a VSB, always check its applicable test standard, tested configuration and current performance information.
At Crowdguard, we only use the most current rating data on our products, which is publicly available on our website – as detailed below.
Vehicle Attack Delay Standard (VADS)
Within the NPSA’s Catalogue of Security Equipment (CSE), is a Chapter for products that have been allocated a rating in accordance with NPSA’s Vehicle Attack Delay Standard (VADS). VADS provides a means for testing Vehicle Security Barriers (VSBs) against aggressive and repetitive vehicle impacts. The VADS has been developed to allow the testing of barriers predominantly used at temporary events. Therefore you will not see all newer products in the security catalogue tested to VADS if they are already in the Impact Rated catalogue.
The point behind VADS-rated products is that acknowledges that the risk profile for temporary events, such as festive markets, is far lower than for an International Sporting fixture (for example), in that it records the delay offered by a product, in the event of a Vehicle as a Weapon (VAW) attack.
HVM and Martyn’s Law
Since this article was first published, the Terrorism (Protection of Premises) Act 2025, commonly known as Martyn’s Law, has received Royal Assent. The Act is not yet in force, with an implementation period underway to give organisations time to understand and prepare for the new requirements. Martyn’s Law does not automatically mean that an event or venue needs Hostile Vehicle Mitigation, nor does it prescribe particular security products. Instead, it reinforces the importance of proportionate preparedness and, for certain larger premises and events, considering reasonably practicable measures to reduce vulnerability to terrorism. HVM may form part of those measures where vehicle-related risk has been identified, but the appropriate response should always be based on the individual location, its vulnerabilities, existing controls and operational needs. In many cases, effective improvements may begin with people, processes and simple operational changes rather than additional physical security.
When it comes to Hostile Vehicle Mitigation, one size does not fit all.
We believe that there is no single HVM solution for every event or public space. This is why we work closely with our clients, partners, and Traffic Management companies to understand the risk and operational requirement before recommending proportionate measures.
Crowdguard has access to a broad portfolio of tested HVM solutions, allowing the specification to be matched to the identified risk and operational requirement rather than forcing every project around a single product.
Our suite of solutions include:
- ATG ‘Surface Guard’
- ARX ‘Stopper!™’
- Highway Care ‘Claw’
- Highway Care ‘RB50’
- Husson ‘H-Stop’
- Unafor ‘Core’
- SVEA barrier
- Armis One
- Armis GO
If you are unsure whether HVM is appropriate for your event, venue or public space, Crowdguard can help you understand the risk before discussing products. Through our Plan · Provide · Protect approach, we assess the requirement, identify practical and proportionate options, and support professional delivery where physical HVM is justified.
Tel: 0161 507 3434
Email: info@crowdguard.co.uk