Fog hides. LIMA SHIELD drives them out.
If you have a fog system, or are torn between the two, you have already grasped the essential point: detecting is not enough, you have to act. A fog generator is genuine active protection with a proven track record. This page compares the two, criterion by criterion, without caricature.
“On a call-out, the best outcome is always the one where the threat leaves of its own accord, without contact. That is exactly what sound can achieve.” Cédric Fontaine, founder of Lima Groupe, former municipal police officer
Comparison checked in September 2026.
If you have a fog generator, you belong to the minority who understand that detecting is not enough. But there are limitations operators discover over time, and they are rarely mentioned at the point of sale.
These limitations do not rule fog out: they mark out where it belongs. And where sound does.
An organised intruder cuts the power before going in. A fog generator, kept heated so it is always ready, lasts a few hours. LIMA SHIELD switches to its internal battery: 1 month of battery life, up to 3 months with secondary batteries, with several deterrence cycles in reserve.
Sound has no colour: throughout the incident, your video surveillance remains usable, for the police and for your insurer. Fog, on the other hand, blinds everyone, including you.
After any activation, real or false: no substance, no residue, no consumables. You deactivate, business is back up and running within a minute, and the system is ready for next time.
Before going into detail, here are the two approaches in brief. They pursue the same goal, defeating the intrusion, but they go about it in opposite ways: one conceals the goods, the other drives out whoever came for them.
Seven criteria, chosen because they are exactly the ones that come up in conversations with retailers and operators already using fog. On several of them, fog keeps the advantage: we say so too.
| Security fog | LIMA SHIELD | |
|---|---|---|
| Power cut | Limited battery life, inoperative after a few hours. | 1 month of battery life, up to 3 months with secondary batteries. |
| Your cameras | The fog hides everything: identification impossible, fire doors close. | Acts without concealing: video surveillance fully usable. |
| False alarm | Lingering residue: clean-up, restoration, business interrupted. | No substance, no residue: immediate return to normal. |
| Legal risk | Total disorientation: possible falls and injuries, potential liability. | Intense deterrence that never traps anyone: the intruder always has a way out. |
| Real costs | Constant heating, continuous power consumption, refills by a technician. | Minimal maintenance, zero consumables, no subscription. |
| Large spaces | Less effective in large and open spaces. | Consistent effectiveness; beyond 100 m², paired devices. |
| Speed | Gradual filling, lag time. | Sound spreads instantly. |
There is no single answer; there is your situation. Here are the cases where sound is the best answer, and those where fog still holds its own.
And the two can be combined: LIMA SHIELD integrates with most existing installations, including those that already have a fog generator.
This is the organised intruder scenario, and it is where the two technologies diverge most: a few hours of battery on one side; on the other, one month, and up to three with secondary batteries, with local detection and alerts over 4G even without a router or Wi-Fi.
The fog paradox: at the very moment something is happening on your premises, it makes your own cameras useless. No usable footage for the police or your insurer. LIMA SHIELD acts while your video surveillance keeps recording.
An accidental fog activation means premises filled with fog, a clean-up, sometimes a closure. With LIMA SHIELD, a false alarm ends with a press on the keypad: no residue, business resumes within a minute.
A French acoustic deterrent device, winner of the Audience Award at the Nuit de la Sécurité Globale (Républik Group). Built-in detection or connected to your alarm, warning beeps, then a sound of 86 to 138 decibels, calibrated to the 2 to 5 kHz band and modulated so the brain never gets used to it: the area becomes unbearable and triggers a flight reflex.
Behind the unit: a French startup, co-founders from the army and the police, engineers, some of them formerly at Dassault, nearly €1 million in research and development, prototypes built in Strasbourg, and compliance with European CE standards.
“These acoustic solutions offer the advantage of complete non-lethality and simplicity (no residue, no cleaning, just noise).” Yoann Le Meur, Medium
Jewellers, tobacconists, warehouses, town halls and police stations already feature among our first customers and pre-orders.
Where fog bills you for constant heating, refills and call-outs, LIMA SHIELD costs €2,500 excl. VAT, once: around 68 cents a day over its 10-year lifespan. And we carry the long-term risk: 2-year manufacturer's warranty, battery excluded.
Yes. LIMA SHIELD integrates with most existing systems via dry contact or radio relay: it can complement an installation that already includes a fog generator, just like any alarm control panel. Fog conceals, sound drives out: the effects add up.
Yes. For indoor use, no French law or regulation known to date caps the power of an acoustic deterrent device, and LIMA SHIELD complies with European CE standards. Its activation in the event of an intrusion falls within the lawful defence of property (article 122-5 of the French Code pénal), with warning, delay and automatic shut-off.
A 10-second delay and warning beeps precede any emission: time to deactivate by code, badge or app. And unlike fog, an accidental activation releases no substance and requires no restoration: business resumes immediately.
The device is CE compliant, traceable by serial number, and its activation is controlled (warning, delay, automatic shut-off). Present it to your insurer as what it is: an additional, documented active protection measure. Your security expert can provide the complete technical file to support the conversation.
Yes, it is in fact one of its strengths: sound spreads instantly and reflects off the walls, with consistent effectiveness in vast or open spaces. One device covers up to 100 m²; beyond that, several paired LIMA SHIELD units coordinate from the same app.
LIMA SHIELD is up and running in 5 to 10 minutes. It is produced in limited runs, and is regularly out of stock.
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