Across Europe and beyond, utilities and critical infrastructures face the same reality: most of their physical assets are unattended sites. These include electricity substations, water reservoirs, gas compression stations, and telecom towers. Such facilities are not staffed permanently and are only visited for inspections, maintenance, or emergency repairs.

This operating model creates a unique security challenge. Protecting unattended sites is critical for business continuity and regulatory compliance, yet traditional security solutions alone are not enough.

The security challenges of unattended sites

Unattended infrastructure facilities are paradoxical: they are essential to modern life yet lack human presence to deter intruders or respond in real time. Because of this, four key risks emerge:

1. Undetected intrusion. At remote sites, unauthorised access may go unnoticed for hours or days. By the time an intrusion is discovered, damage or service disruption may already have occurred.
2. Inefficient mechanical key management. Mechanical keys are difficult and costly to manage across dispersed networks. Delivering, revoking, or collecting keys wastes resources. Lost or copied keys add security risks. Technicians may even travel long distances only to discover their key does not fit, causing delays and higher costs.
3. Compliance with regulations. Regulations such as NIS2 and KRITIS require operators to demonstrate strict control of access rights and maintain auditable records. Purely mechanical systems cannot provide the digital trail needed for audits, exposing operators to penalties.
4. Limited incident response. When incidents occur, operators need accurate data to investigate and prevent recurrence. Without reliable access logs, incident response becomes slow and incomplete.

Why traditional security solutions fall short

Mechanical security alone. While mechanical locks are durable, they lack agility. Revoking access often requires changing cylinders, which is costly and inefficient at scale.

Purely digital security. Digital systems may seem advanced, but they come with vulnerabilities. Credentials can be cloned or hacked, and keyless devices require exposed antennas (RFID, BLE, NFC), leaving them fragile and open to tampering.

For unattended critical infrastructure, neither mechanical nor purely digital systems alone provide sufficient resilience.

A hybrid solution: ISEO’s LSA and F9000

ISEO offers a hybrid access control system designed for the realities of unattended sites. It combines the LSA platform for centralised digital management with the F9000 mechatronic key for secure, on-site access.

The LSA platform: centralised digital control. The LSA platform provides remote management of access permissions. Operators can grant or revoke authorisations instantly, limit access by time, task, or duration, and maintain a full audit trail of all access events. The platform also integrates with existing tools such as CMMS, asset management systems, and work order platforms. This ensures that access management aligns with operational workflows, improving both security and efficiency.

The F9000 mechatronic key: dual verification. The F9000 key combines mechanical precision with digital authorisation. To unlock, the key must both fit the cylinder and carry valid digital credentials. This dual verification prevents unauthorised entry even if a digital credential is compromised. For example, a technician may be granted one-day access, download authorisation to their key, and complete their task without leaving long-term vulnerabilities. All activity is logged, supporting both compliance and incident response.

Benefits of hybrid security for critical infrastructure

Adopting a hybrid security system delivers clear advantages for utilities and operators:

• Enhanced protection against both physical and cyber threats;
• Regulatory compliance with full, auditable access records;
• Reduced operational costs, by eliminating wasted travel and complex key logistics;
• Improved workforce management, with precise, time-bound access for employees and contractors;
• Business continuity, ensuring uninterrupted service even under attempted attack.

Securing unattended sites is essential for modern utilities. Traditional systems fall short, but ISEO’s hybrid LSA and F9000 solution combines mechanical strength with digital intelligence to ensure compliance, resilience, and uninterrupted service.

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