Car dealerships face three security threats simultaneously. High-value vehicles are on display under lights. Keys are stored onsite, often in inadequately secured locations. Keyless relay attacks can unlock vehicles remotely, bypassing traditional locks entirely. A showroom routinely holds hundreds of thousands in inventory. The key store is frequently a single point of failure. Relay attacks have become common enough that major insurers now flag them as a named threat.
Security fog fixes all three at once. When an alarm triggers it, fog fills the space in seconds. Thieves cannot see. They cannot move. They cannot steal. The result is stark: 97% of thefts are avoided with a fogging system and an alarm, compared with 17% with an alarm only—a Density® manufacturer figure.
The Triple Threat: Inventory, Keys, and Keyless Relay Risk
Showroom vehicles are visible targets under permanent lighting. After hours, if perimeter security is breached, they are fully accessible. One night of absent monitoring can cost dealerships tens of thousands in vehicle theft or damage.
The key store represents the highest-value risk. Thieves with key store access can start and drive away multiple vehicles in minutes. Many dealerships store keys in cabinets that are relatively easy to force or bypass. Night-shift staff and external contractor access compound this vulnerability significantly.
Relay attacks are an emerging threat that bypasses traditional security entirely. A criminal positioned outside the premises uses a signal booster to eavesdrop on keyless transmissions from vehicles inside the showroom. The booster then relays this signal to an accomplice inside, allowing them to unlock and start the vehicle without possession of the fob. Standard alarms frequently miss this attack because the vehicle’s own security system perceives the relayed signal as legitimate. Fog eliminates the threat: if the thief cannot see the vehicle, the relay attack becomes physically impossible to execute.
How Fog and Alarm Integration Protects Showrooms
An alarm detects intrusion. Fog then removes the advantage a thief needs most: visibility and time. Fog fills the space in 8–15 seconds. Once fog deploys, thieves cannot see vehicles, cannot navigate, and cannot operate with speed.
Integration is straightforward. Density fog systems are certified to EN 50131-8:2019, the global standard for electronic security. They work with all existing alarm panels—no rewiring or equipment replacement required. If your dealership has a hardwired system or a wireless platform such as Ajax, the fog generator connects directly. When the alarm detects a breach, it sends a trigger signal to the generator automatically.
Add free remote monitoring via ActiveCloud for real-time alerts. If fog deploys, your phone receives an instant notification with timestamps and location details. You can then contact police with precise information about the incident and respond in real time.
Sizing: Showrooms and Key Stores
Security fog coverage is measured in cubic metres (m³)—the actual volume the system can protect, not merely floor area. A single-bay showroom holding four to six vehicles typically requires between 900 and 1,500 m³ of coverage depending on ceiling height. The Density 900 generator covers up to 900 m³, while the Density 1500 Lite covers up to 1,500 m³. Both units deliver complete fog coverage in under one minute from trigger.
Larger multi-bay showrooms or combined service areas require the Density 2400, which covers up to 2,400 m³. Key stores occupying small office space can be protected independently with a Density 600 Lite (up to 600 m³), or integrated as a secondary trigger zone within the main showroom protection system.
Fog reaches all areas—above high shelving, into corners, around vehicle interiors, and through the entire vertical space. The generator is permanently installed near a primary entry point or in a roof cavity. Once the alarm detects a breach, the system deploys automatically. No staff intervention is required.
Why Relay Attacks Require Active Defence
Relay attacks are silent. CCTV misses them—the attacker stands outside. Locks and alarms alone cannot stop them. A two-person team can steal a car in under three minutes.
Fog changes this. Once triggered, relay attacks fail. The thief cannot see. Cannot navigate. Cannot work fast. Fog response is faster than the attack plan.
Will fog damage vehicles?
No. Density fog is non-toxic, certified by Eurofins. It is safe for humans and animals. It leaves no oily residue. It does not stain upholstery or paintwork. The fog clears within hours.
How fast does fog activate?
Fog fills a showroom in 8–15 seconds. An alarm detects the break-in and sends the trigger signal immediately. This is faster than a thief can locate and reach a vehicle. Speed is what makes fog work.
97% of thefts are avoided with a fogging system and an alarm, compared with 17% with an alarm only. This is the Density® manufacturer figure, combining both layers.
Frequently asked questions
How does fog stop relay attacks if the thief is outside?
Relay attacks work only if the thief inside can reach and steal the unlocked car. Fog fills the showroom so the thief cannot see or move. The attack fails at the execution step.
Can I add fog to my existing alarm?
Yes. Density systems work with all existing alarms. No rewiring needed. The generator installs in the roof or near a door. The alarm triggers it on intrusion. Installation takes a day.
What size system for a three-bay showroom?
Three-bay showrooms need 1,500–2,400 m³ depending on ceiling height. The Density 1500 Lite or 2400 works well. A survey will confirm the right size for your space.
Does fog leave residue on vehicles?
No. Fog is non-toxic and residue-free. It clears within hours. It does not stain upholstery, leather, or paint.
Can the system send alerts to my phone?
Yes. Add free remote monitoring via ActiveCloud. If fog triggers, you get an instant alert with timestamps and location details. You can call police with exact information.
Related Car Dealerships security guides
- Securing the Dealership Key Store Overnight — detailed security protocol for protecting keys when they are your highest-value target.
- Why Forecourt Cameras Aren’t Enough — understanding the limits of CCTV alone in deterring organised vehicle theft.
- How Security Fog Protects a Dealership Showroom — the tactical breakdown of fog response to active theft in progress.
- Car Dealerships sector page — overview of Density solutions tailored to dealership security challenges.
Showroom security is multi-layered. Vehicles need protection. Keys need restricted access. Systems must be fast. Density fog systems do all three, paired with your alarm.
If you run a dealership with high-value stock, a security fog audit can find gaps in your current setup. Get in touch for a site survey tailored to your showroom and key store.
