When a storm hits a public building, protection is never simply a matter of a rooftop device. It combines building design, electrical continuity, fire prevention, and a human-centered procedure capable of evacuating people at the right time. This principle applies in all countries implementing IEC 62305, and it is particularly crucial for facilities that house children, patients, or dependent individuals.
On September 16, 2026, a lightning strike triggered a fire at the Chantevents care home in Corsavy, Pyrénées-Orientales. According to France 3 Régions, thirty children and teenagers were evacuated, and no injuries were reported. This local event highlights a universal issue: anticipating storms so that the safety of residents does not depend on a hasty decision.
What the Corsavy incident reveals
A public access building (ERP) is a building where members of the public are admitted, with safety requirements adapted to its activity and the people it serves. In a residential care facility, evacuation must take into account the number of people present, staff, individual needs, and the continuity of information.
In Corsavy, the fire broke out after a lightning strike, and emergency services evacuated the residents. Therefore, the case should not be reduced to a simple account of the impact; it highlights the complete chain of events that links a weather phenomenon to an alert, an evacuation decision, and then the site's recovery.
- Before the storm : identify safe areas, those in charge, and evacuation routes.
- During the alert : suspend exposed activities and communicate a simple, verifiable instruction adapted to the public.
- After the event : protect people, alert emergency services if necessary, then check the installation and equipment.
Why lightning can start a fire
Lightning is a high-intensity electrostatic discharge that occurs when the electric field of the atmosphere causes the air to break down. The lightning channel reaches approximately 30,000 °C; thus, a strike can produce a thermal effect at the point of contact, damage a roof, or ignite vulnerable materials ( LPS France, Fact Sheet 01).
However, direct impact is not the only mechanism to consider. Induced surges, temporary rises in ground potential, and coupling via power or data lines can affect alarms, automation systems, boiler rooms, and electronic equipment. Therefore, comprehensive lightning protection addresses both direct and indirect effects.
- An external system aims to capture the current, conduct it and dissipate it to the ground.
- Internal protection aims to limit overvoltages on incoming equipment and networks.
- Equipotentiality connects conductor elements to reduce dangerous potential differences.
How to protect a public building from lightning?
A public access building (ERP) is protected by combining a risk assessment, physical protection, and a documented alert system. Protecting the building reduces the likelihood of physical damage and network failures; the system, in turn, allows people to be sheltered before a storm escalates into a crisis.
The international standard IEC 62305 structures risk analysis. It examines, in particular, the impacts on the building structure, its immediate surroundings, incoming lines, and the areas surrounding these lines. The objective is therefore not to install equipment automatically, but to determine measures tailored to the building, its occupants, and its networks.
- Carry out or update the risk analysis when the building, its use or its lines change.
- Define the external protection system, surge arresters and Equipotential Spark Gap required by the project.
- Prepare an alert, shelter-in-place and evacuation procedure understood by each team.
- Test the procedure and keep a record of the checks, exercises and corrective actions.
From weather alert to evacuation: a prepared decision
A real-time alert is information that signals the approach or presence of storm activity in order to trigger a pre-established procedure. It does not replace a risk analysis or a protection system; however, it gives those in charge the necessary time to interrupt an outdoor activity, secure a group, and reach an enclosed building.
In this context, Sky Sentinel is designed for real-time alerts. The tool must operate within a clear procedure: who receives the information, who decides, what message is transmitted, where occupants gather, and when resumption of activity becomes possible. Furthermore, the same scenario must cover visitors, service providers, and individuals requiring assistance.
- A designated person in charge and a substitute should be assigned to each time slot.
- Define short, jargon-free messages for stopping activities and sheltering in place.
- Avoid open spaces, makeshift shelters and areas near exposed elements during the storm.
- Maintain backup communication equipment when the main power supply is cut off.
Protecting the building, but also its equipment
A lightning protection system is only complete if it takes into account the building structure and internal networks. IEC 62305-2 specifically distinguishes between physical damage and failures of internal networks; therefore, a project must examine essential equipment such as fire alarms, communications, heating, automation, and video surveillance.
AtmoGuard can contribute to an approach that ensures equipment resilience and business continuity, within the limits defined by the site assessment. Subsequently, a professional inspection should verify the condition of components, connections, grounding, and surge protection devices. No solution should be presented as an absolute guarantee: it reduces an identified risk and must be maintained.
- Document the plans, component references and reference measurements.
- Check surge arresters, conductors and grounding points according to applicable requirements.
- Trigger an exceptional inspection following a significant event or building modification.
Traceability transforms prevention into proof
After a storm, teams need to know what was observed, what was done, and what still needs to be checked. Traceability is the dated record of events, documents, checks, and decisions associated with a facility. It prevents information from being scattered across email inboxes, paper files, and individual memories.
Once the installation is defined, LPS Manager helps centralize the execution file, schedule checks, and maintain keraunic reports and certificates accessible via Strike Radar. This allows the manager to prepare for the next intervention based on documented facts rather than a post-hoc reconstruction.
- A weather event can be associated with the site and a control action.
- The verification reports and photos remain accessible along with the installation history.
- Deadlines make it easier to track corrective actions and responsibilities.
Conclusion: Prevention that links technology and organization
The Corsavy incident demonstrates how lightning can quickly transform a storm into an emergency evacuation. However, the most robust response is prepared well before the storm: risk analysis, external and internal protection, alert procedures, training, and verification. Furthermore, traceability allows for the preservation of the necessary evidence to monitor and improve the system. For public buildings internationally, as well as for care facilities, protecting people therefore requires linking the building, its equipment, and human decisions within a single approach.
