OT Security Engineer

Security OT Engineer

Rate: £500 – £550 Inside IR35

Duration: 6 months

Location: South West (Bristol) – 2 days per week onsite

The Role:

We’re hiring an experienced Security OT Engineer to support the protection and evolution of complex Operational Technology (OT) and industrial control system environments.

This role sits within a Security Operations function but is heavily engineering-focused, combining hands-on OT security tooling, detection engineering, and incident response to strengthen resilience across critical infrastructure.

Key Responsibilities:

• Act as the OT security engineering SME, supporting both operational and project based activities
• Engineer, configure and optimise OT security platforms (e.g. OT NDR tools such as Claroty or equivalent)
• Develop and refine detection rules, alerting logic and monitoring coverage across OT and IT/OT convergence points
• Lead technical investigations and incident response for OT-related cyber events
• Analyse industrial network traffic to identify anomalies, threats and protocol misuse
• Integrate OT telemetry into SIEM and EDR platforms to enhance visibility and correlation
• Support secure by design initiatives for new OT systems, including segmentation and access control validation
• Assess vulnerabilities in OT systems and implement practical, risk-based remediation strategies
• Drive continuous improvement in OT security posture, tooling effectiveness and detection capability
• Maintain and enhance OT security documentation, playbooks and engineering standards

Experience Required:

• Proven experience in a Security OT Engineer / OT Cyber Security role
• Strong understanding of industrial control systems (ICS) – including SCADA, PLCs, DCS
• Hands-on experience with OT security tools (e.g. Claroty, Nozomi, Dragos or similar NDR platforms)
• Solid knowledge of industrial protocols (e.g. Modbus, DNP3, OPC, Profinet)
• Experience with SIEM, EDR and network traffic analysis (e.g. Wireshark)
• Background in incident response, threat detection and security monitoring within OT or converged environments
• Understanding of network segmentation, secure remote access and OT architecture design
• Familiarity with frameworks such as ISA/IEC 62443 and MITRE ATT&CK for ICS

Desirable:

• Certifications such as GICSP, ISA/IEC 62443, Security+, or CEH
• Experience working in critical infrastructure or regulated environments
• Exposure to threat hunting and purple team activities within OT environments

Key Skills & Attributes:

• Strong engineering mindset with a focus on building and improving security capability
• Ability to balance security requirements with operational safety and uptime
• Analytical, detail-oriented and comfortable working with complex OT environments
• Confident communicator, able to engage across security, IT and engineering teams
• Proactive and solution-driven with a focus on continuous improvement