OT Security Lead

Digital Waffle; West of England; On-site; GBP 68,000 - 83,000; Full time

Job summary

Digital Waffle in Bristol is seeking a Senior OT Security Engineer to lead secure design and implementation of security for critical infrastructure projects in the energy sector.

You will provide expert guidance for secure-by-design solutions, design robust security architectures for software and hardware, and maintain cybersecurity models aligned with IEC 62443 and IEC 62351 while mentoring teams and delivering FAT/SAT related work.

Qualifications

• CISSP or IEC 62443 credentials earned or in progress.
• OT/ICS experience in operational environments.
• Knowledge of IEC 62443 and IEC 62351 standards.
• Understanding of IEC 61850 substations and related protocols.
• Awareness of regulatory frameworks such as NIS2.
• Familiarity with PRP and HSR network topologies.
• Experience with security technologies including firewalls, IDS, VPNs and encryption.
• Strong communication with technical and non-technical stakeholders.

Responsibilities

• Provide expert cybersecurity guidance to project teams across engineering, development and service delivery, ensuring secure-by-design solutions.
• Design and implement robust security architectures for software and hardware components.
• Develop cybersecurity frameworks aligned with IEC 62443 and IEC 62351.
• Identify and implement improvements to cybersecurity processes and efficiency.
• Produce and oversee FAT and SAT documentation, leading security validation activities.
• Mentor project teams with specialist advice on product and system security.
• Deliver internal training sessions to raise cybersecurity capability.
• Track, assess and communicate security risks and mitigation plans to leadership.
• Ensure adherence to corporate policies and best practices for sensitive information handling.
• Promote a safety-first culture in the workplace.

Skills

CISSP or IEC 62443 credentials

OT/ICS experience

IEC 62443 and IEC 62351 knowledge

IEC 61850 understanding

NIS2 awareness

PRP/HSR knowledge

Security technologies (firewalls, IDS,

Strong stakeholder communication

Tools

Firewalls

IDS

VPNs

Encryption protocols

Job description

Location: Bristol Salary: Up to £75,000 + Bonus + 10% Pension

A leading engineering and technology organisation within the energy sector is seeking a Senior OT Security Engineer to support the delivery of secure, resilient solutions across critical infrastructure projects. This role plays a key part in strengthening the security of systems that underpin the UK's energy network, contributing to a more intelligent and sustainable future.

Key Responsibilities

• Provide expert cybersecurity guidance to project teams across engineering, development and service delivery, ensuring secure-by-design solutions.
• Design and implement robust security architectures for both software and hardware components, in line with customer and regulatory expectations.
• Develop and maintain cybersecurity frameworks and models for new and existing systems, aligned with recognised standards such as IEC 62443 and IEC 62351.
• Identify and implement improvements to cybersecurity processes, enhancing both protection levels and operational efficiency.
• Produce and oversee Factory Acceptance Testing (FAT) and Site Acceptance Testing (SAT) documentation, leading security validation activities.
• Support and mentor project teams throughout the full lifecycle, offering specialist advice on product and system security.
• Deliver internal training sessions to raise awareness and capability in cybersecurity practices.
• Track, assess and communicate security risks, issues and mitigation plans to stakeholders and leadership teams.
• Ensure adherence to corporate policies, compliance requirements and best practices for handling sensitive information.
• Promote a strong safety-first culture, supporting initiatives that prioritise safe and responsible working environments.

Skills & Experience

• Professional cybersecurity certification completed or underway, e.g. CISSP or IEC 62443-related credentials.
• Practical experience within Operational Technology (OT) environments or Industrial Control Systems (ICS).
• Familiarity with industry standards including IEC 62443 and IEC 62351.
• Understanding of substation automation, protection technologies and communication protocols such as IEC 61850.
• Awareness of regulatory frameworks such as NIS2 and associated security level requirements.
• Knowledge of industrial network topologies, e.g. PRP and HSR.
• Experience with security technologies including firewalls, intrusion detection systems, VPNs and encryption protocols.
• Strong communication skills, with the ability to engage both technical and non-technical stakeholders.