Everything we get asked about the sound shield.

It is an acoustic deterrent device which, once an intrusion is confirmed, warns the intruder with a sequence of beeps, then emits a very high-intensity sound that makes the area unbearable and triggers a flight reflex. Unlike an alarm, which detects and alerts, it acts during the intrusion: without contact, without any substance and without confrontation. LIMA SHIELD emits 86 to 138 decibels in the 2 to 5 kHz band, where human hearing is most sensitive.

Passive protection records and alerts: that is what alarms, cameras and remote monitoring do, and they do it well. Active protection acts on the intrusion while it is happening. That matters because a burglary lasts 6 to 12 minutes on average, whereas an alarm has done its job within a few seconds: everything that follows happens without it.

Because it is not just a question of volume. A siren is a constant sound: the brain gets used to it, and experienced intruders know this. The LIMA SHIELD signal is modulated several times per second, which prevents habituation: the reference work in psychoacoustics (Zwicker and Fastl) shows that a tonal, modulated sound is judged significantly more unbearable than continuous noise at the same level. See the science in detail.

Up to 100 m² per unit, depending on the layout of the space and its acoustics: volume, reverberation, materials. Think in terms of zones to hold rather than total floor area: units go at strategic points, such as entrances, storerooms and choke points. Beyond that, several Shields can be paired from the app and work together.

Yes, by pairing them from the Lima Shield Connect app. Each unit communicates with the others and can be controlled individually or together, so large areas, multi-level buildings and multiple sites can be covered evenly.

The sound waves it emits do not pass through walls. Tests show that the noise stays within the protected area: outside, the neighbours hear at most the equivalent of an alarm siren slightly louder than average.

It is difficult, and deliberately so. Indoors, sound bouncing off the walls wipes out directional cues: the source seems to be everywhere, an effect documented in room acoustics (Kuttruff, ISO 3382). On top of that comes tamper protection: any attempt to tear the unit off sets off the deterrent.

Yes, for indoor use. No French law sets a decibel ceiling for an acoustic deterrent device used inside an enclosed private or professional space. The product complies with European CE standards, and activating it in the event of an intrusion falls within the self-defence provisions of article 122-5 of the Code pénal (French Criminal Code), as long as the response is necessary, simultaneous and proportionate. The full legal framework is set out here.

Because the law and technical standards are often confused. The 115 dB limit comes from the technical standards for alarm sirens: above it, a device can no longer be classed as a siren within the meaning of those standards. It is not a ban. LIMA SHIELD is not a siren: it belongs to a separate category, acoustic deterrent devices, whose purpose is not to alert people nearby but to make an intrusion unbearable.

Yes, provided the product is CE compliant and used indoors as a deterrent device. What can be penalised is not the device itself but its misuse: deliberate noise nuisance, triggering it without cause, deliberately exposing third parties.

Yes, for indoor use and under the same conditions. The warning beeps, the 10-second delay and the automatic shut-off exist precisely for these settings: they let you protect the site while staff and the public are present.

We were advised by lawyers specialising in new technologies at every stage of development, and we remain in constant dialogue with the regulator and law enforcement. Innovating in security means breaking ground the law has not anticipated: we prefer not to do it alone.

The device always includes a warning phase, a sequence of beeps, giving people time to leave the area before any sound is emitted. When it is triggered, a person at a normal distance who is briefly exposed experiences only temporary effects, such as discomfort in the ears and ringing, which fade within a few minutes. The sound alternates with pauses and stops automatically at the end of the set duration. As with any high-intensity acoustic device, real risks arise only with very close and prolonged exposure, outside the intended conditions of use.

The sensors are designed to recognise small frames and low-level movement: a cat or a young child has virtually no chance of triggering the system. Since no sensor is infallible, protection does not rely on it alone: the warning beeps and the delay come before any sound is emitted, and disarming is just a code, a badge or a phone away.

The device faces the areas to be protected, not workstations, and it is armed when the site closes. Where the entrance opens directly onto the protected area, a 10-second delay gives staff time to disarm it on arrival. If it is triggered briefly by accident, there are no lasting effects to fear, and unlike security fog, there is no substance released and no clean-up: you disarm, and work resumes.

Covering your ears with your hands is not enough: the discomfort remains intense and quickly unbearable. Even with real hearing protection, an unlikely scenario given the element of surprise, the sound pressure is felt physically, notably as vibrations in the skull and chest. The intruder remains disoriented, unable to communicate and deprived of any useful perception of their surroundings.

That is neither its purpose nor how it is designed. LIMA SHIELD is designed to deter, not to injure: it makes an area unbearable so that intruders retreat, always leaving them a way out. Intensity and duration are adjustable, and a range of 128 to 133 dB is generally enough to achieve the intended effect without reaching the thresholds associated with permanent damage during a short exposure.

No. Two screws for the wall bracket, or a freestanding stand, plus a socket; setup is then done over Bluetooth from the app: allow 5 to 10 minutes. For integration with an alarm control panel or a multi-site deployment, a demonstration with an expert will help you plan the layout.

No. Detection and triggering happen locally and do not depend on any network. Wi-Fi adds convenience, with notifications and remote control, and the built-in 4G takes over when there is none. A cellar, a workshop or a construction site without broadband is protected exactly like a living room.

The internal battery takes over automatically: up to 1 month on standby, with several deterrence cycles in reserve, and up to 3 months with the optional secondary batteries. A full recharge takes 3 to 4 hours. A power cut, accidental or deliberate, does not disarm the device.

With most professional systems, yes: a universal wired dry-contact connection, or a radio relay via compatible modules from your alarm's manufacturer. It then uses your existing detectors and cameras. With a fully wireless consumer alarm, which is more vulnerable to jamming, it is better to run it entirely on its own, with its own infrared and thermal detection.

In two ways. Automatically, after an intrusion is detected and confirmed, with warning beeps followed by a 10-second delay. Or manually, by panic button, remote control or app, even if the device is not armed: this is what lets you respond to an assault in broad daylight. Details of the accessories are here.

Real-time notification through the Lima Shield Connect app, relayed by the built-in 4G to ensure you are informed even in the event of a power or network outage. Several recipients can be alerted at the same time.

Yes, this is common on construction sites and between homes: removal and reinstallation in 5 to 10 minutes, transport in a hard case, reconfiguration from the app. The device is mobile and requires no heavy infrastructure.

Indoors and in sheltered semi-outdoor areas: garage, technical room, covered area, sheltered loading dock, container, site cabin. Its protection rating is IP54, resistant to dust and splashing water, but the unit must not be directly exposed to the weather.

No, and it is not designed to. Your alarm detects and alerts, remote monitoring dispatches people, and LIMA SHIELD acts on site during the minutes when no one has arrived yet. It connects to your existing system by dry contact or radio relay, and it works without a subscription.

Yes: the devices are triggered from the same installation and their effects add up. This is common at jewellers and tobacconists, where this type of device is already in place.

A French startup, a subsidiary of Lima Groupe, an integrated security group whose co-founders come from the army and the police. The design is French, nearly €1 million has been invested in research and development, and the prototypes were made in Strasbourg. The team brings together acoustic, electronics and software engineers with backgrounds in defence. Our story is here.

Yes: LIMA SHIELD received the Audience Award at the Nuit de la Sécurité Globale, the leading event in the security sector, organised by Républik Group, which describes it as “derived from military technology adapted for civilian use”. The device was also featured in Le Figaro, which calls it “a disruptive innovation in the field of security”.

€2,500 excl. VAT per unit, paid once, with no subscription. Spread over its 10-year lifespan, that comes to about 68 cents a day. Compare that with the total cost of a burglary, from around €2,000 to €95,000 depending on the extent of the loss, once you count stolen property, damage, repairs, the excess and the impact on your insurance policy.

None. No monthly subscription, no refills, no product to replace, no technician call-out after an activation. Maintenance is annual, and only the battery needs periodic replacement. Software updates are done remotely, free of charge.

The manufacturer's warranty: 2 years, repair or replacement, excluding the battery. On top of that, dedicated technical support in Europe and traceability through a unique serial number.

LIMA SHIELD is produced in limited runs, with a production time of 4 to 8 weeks per run. Demand currently exceeds supply and stock often runs out: if the device is in stock when you order, that is the moment to buy.

Jewellers, tobacconists, luxury boutiques, warehouses, car dealerships, town halls and police stations are among the first to have bought or pre-ordered, alongside private individuals. Le Figaro notes that the device “is already attracting interest from individuals and businesses, as well as institutional and military players, in France and abroad”.

There is no camera on a LIMA SHIELD: detection relies on infrared and thermal analysis, and no image is ever captured or stored, which makes compliance with the GDPR and CNIL rules simpler. Communications are encrypted and the entire product has undergone a cybersecurity audit, so that no third party can take control of it remotely.