Hostile vehicle mitigation for events: planning barriers

A square full of people with a road running along one side: for a Christmas market, a town festival or a parade, this is the normal situation. Since the vehicle ramming attacks of recent years, licensing authorities and the police increasingly ask for a hostile vehicle mitigation (HVM) concept. At the same time, many organisers are unsure what such a concept must contain, who is responsible for it and which barriers actually protect.

This article sets out the essentials: the process described in the German police handbook, the standards for vehicle security barriers and the calculation behind every access point. It is not a substitute for specialist planning.

Who decides – and who advises

The handbook “Schutz vor Überfahrtaten” (protection against vehicle ramming) published by Germany’s police crime prevention service is written for towns and municipalities. It assigns clear roles:

Role	Task
Risk owner	overall responsibility, decides on resources and the acceptable residual risk – usually the municipality or the organiser
Risk manager	runs the process, assesses risks, keeps the risk management file
Police	contribute the threat picture and local crime situation, advise impartially
Specialist planner	prepares the HVM concept, specification and cost plan
Installer, operator, maintainer	install, operate and maintain the barriers

The handbook makes one point very clearly: the police will not take the fundamental decisions. Whoever is responsible for the event must also decide on vehicle protection – and be able to justify that decision. One possible outcome is that, in a specific case, no HVM measures are needed.

Six steps to a concept

The handbook divides the work into six steps. DIN SPEC 91414-2 was developed on the basis of the handbook and goes into the planning in more depth.

1. Preliminary considerations: involve those responsible – administration, security authorities, residents, organisers. Barriers that are only meant to reassure, without tested protective performance, should be avoided.
2. Threat analysis: visitor numbers, significance of the location, political, religious or cultural context. Likelihood and severity are assessed in a risk table; a threat assessment grid helps.
3. Protection objective: define it as precisely as possible, for example “Entry into the protected area by a vehicle with a gross weight above 7,500 kg is to be prevented.”
4. Protected zone: mark the area to be protected on a map and record every possible access route, including emergency routes, escape routes and access needed for deliveries or residents.
5. Protection concept: assess the approach routes for every access point and calculate the impact energy; reduce speed through design wherever possible.
6. Choice of protection systems: only tested and certified products, followed by a fresh assessment of the residual risk.

Every access point counts

The most common planning mistake is to look only at roads. The handbook explicitly requires every possible access route to be considered – including footpaths and cycle paths that lead into the protected zone through a park or under arcades. On open fields and festival meadows, the open edge must be added: wherever there is no ditch, wall or building, a vehicle can approach straight across the grass.

The handbook is equally clear about apparent obstacles: parked vehicles, small street trees, street lights and glass façades generally offer no protection. The same applies to stage structures, containers or tents that have not been tested as vehicle barriers.

Why speed matters most

A barrier has to absorb the energy with which a vehicle strikes it. This impact energy depends on mass and speed (E = ½ · m · v²) and grows with the square of the speed. A longer run-up therefore raises the energy far more than one might expect:

Vehicle (test mass)	30 km/h	50 km/h	80 km/h
Car (1,500 kg)	52 kJ	145 kJ	370 kJ
Van (3,500 kg)	122 kJ	338 kJ	864 kJ
Lorry (7,200 kg)	250 kJ	694 kJ	1,778 kJ
Lorry (30,000 kg)	1,042 kJ	2,894 kJ	7,407 kJ

The speed a vehicle can reach at an access point depends on the length of the run-up, on bends and junctions and on the vehicle itself. The legal speed limit is irrelevant – an attacker will not respect it. That is why the German police catalogue of requirements for HVM planners calls for a vehicle dynamics analysis for every single access point. The calculated energy must be below the test rating of the barrier installed there.

The energy can also be reduced: traffic islands, offset lanes, braking bends and chicanes in front of the barrier shorten the distance over which a vehicle can accelerate.

Standards and tests at a glance

Document	Content
DIN SPEC 91414-1:2021	German test standard for mobile barriers, with additional displacement and tamper tests
TR “Mobile Fahrzeugsperren” (police)	German police procurement guideline; protection classes SK1 (800 kJ), SK2 (1,950 kJ), SK2+ (2,400 kJ and above), each for paved (B) or unpaved (U) ground
ISO 22343-1:2023	international test standard for fixed and mobile barriers, replacing IWA 14-1 and PAS 68
DIN SPEC 91414-2:2022	requirements for planning vehicle access protection
ISO 22343-2:2023	selection, installation and application of vehicle security barriers

Products tested under the older methods IWA 14-1, PAS 68 or ASTM F2656 keep their test certificates. Test results are given as a code, such as V/7200[N3C]/80/90:5.2/6.5: a 7,200 kg vehicle at 80 km/h, impact at a right angle, 5.2 m penetration, major debris up to 6.5 m. For lorries, penetration is measured from the front of the load bed – so the actual penetration can be greater.

This leads to a planning rule: a barrier does not belong right at the edge of the crowd. Space is needed behind it for penetration and debris.

Emergency routes and operation

A barrier that holds up the emergency services creates a new risk. Fire brigade, ambulance and police need access – under DIN 14090 at least 3 m wide. Escape routes must stay open despite the barriers. These locations need barriers that can be opened, and staff who know when to open them and who does it.

The handbook also notes that some mobile barriers can be moved by hand and must therefore be guarded. A concept therefore includes operation: who checks that the barriers are still correctly in place? Who opens up for an ambulance and closes again afterwards?

How MOVETOS OPS helps

In the MOVETOS OPS platform, vehicle protection is a dedicated planning step. The platform finds every point on the map where a drivable route reaches the visitor area – roads as well as farm tracks, footpaths, cycle paths and open field edges. For each of these barrier points it estimates how fast different vehicle classes can arrive and with what impact energy. The catalogue lists vehicle barriers with their ratings from the common test methods. Emergency exits and access for emergency services from the rest of the plan are taken into account.

The result is a proposal for the specialist planner, not a finished concept: the system suggests, a person approves. During the event, the cameras on the masts show the control room the access points as part of the live situation picture, announcements reach visitors even without mains power or a network on site, and the operation is fully documented. How announcements are planned for markets and fairs is covered in Christmas market safety: reassessing markets and fairs.

Checklist for organisers

• Clarify responsibility: who is the risk owner, who plans, who operates the barriers?
• Involve the police early: the threat picture and local knowledge belong in the analysis.
• Write down the protection objective: which vehicle must be stopped – and where?
• Record all access routes: including footpaths, cycle paths, farm tracks and open edges.
• Calculate every access point: achievable speed and impact energy for each one.
• Certified barriers only: ask for the test certificate and compare it with the calculated energy.
• Allow for distance: keep the penetration and debris zone behind the barrier clear.
• Secure rescue and escape: access for emergency services, open escape routes, clear responsibility for opening.
• Define operation: guarding, barrier checks, an emergency plan for the residual risk.

Conclusion

Hostile vehicle mitigation is not a matter of a few concrete blocks. It is a concept with clear responsibility, a traceable threat analysis and a calculation for every access point. Organisers who plan early, record every access route and use only certified barriers protect visitors effectively – and can justify their decisions later.