OT Security Specialist

OT Security Specialist

Full-Time 59000 - 72000 £ / year (est.) Home office (partial)
ISS

At a Glance

  • Tasks: Join our team to enhance OT security across global manufacturing sites and engage with engineering teams.
  • Company: FTSE 100 company focused on cyber security and operational technology.
  • Benefits: Competitive salary, Bupa health coverage, matched pension contributions, and hybrid working options.
  • Other info: Dynamic role with opportunities for growth and direct impact on operational safety.
  • Why this job: Be at the forefront of cyber security in manufacturing, making a real difference in safety and operations.
  • Qualifications: 5+ years in cyber security with hands-on OT experience; strong technical knowledge required.

The predicted salary is between 59000 - 72000 £ per year.

The Group Cyber Security (GCS) team is responsible for managing cyber risk appropriately across the Group and has recently refreshed its cyber strategy, with a renewed focus on embedding cyber security as part of the culture and DNA. The Group operates a highly federated business model spanning 11 divisions and over 50 countries, and the cyber strategy has been designed to build materially improved security capabilities whilst working with a divisional focus.

It is an exciting time to join GCS. We are in a period of significant investment, with a multi-year transformation programme under way to build new security capabilities at pace. The business, whose resilience depends on keeping production lines running, plants safe, and supply chains intact, the security of operational technology is fundamental.

The OT and Manufacturing Security team sits at the heart of that mission – setting the Group OT security standard, driving improvement across the global manufacturing estate, and ensuring that the people, processes, and technologies running the plants are protected against an evolving threat landscape.

Role Summary

Reporting to the OT and Manufacturing Security Manager, the OT Security Specialist is a hands‑on technical expert who provides specialist OT security knowledge, assessment capability, and practical delivery support across the manufacturing and operational technology environments. The role sits close to the operational reality of its plants – engaging directly with divisional engineering teams, system owners, and plant management to assess OT security risks, support the implementation of security controls, and build security awareness in communities who may not have a traditional cyber background.

The OT Security Specialist combines deep technical knowledge of OT environments – SCADA, ICS, PLCs, DCS, and the protocols that connect them – with a practical understanding of how security improvements must be designed and sequenced to respect the availability, safety, and operational constraints of manufacturing environments. This is not a purely desk‑based role: it requires regular site visits, direct engagement with plant engineers, and the ability to earn trust in a world where cyber security may be seen as a new and sometimes unwelcome intrusion.

The role supports the OT and Manufacturing Security Manager across the full range of OT security activities – from risk assessment and vulnerability management, through Claroty deployment and monitoring, to incident response support and the delivery of OT‑specific security awareness programmes. The OT Security Specialist is a critical delivery resource within the team and a key technical interface between Group Cyber Security and the operational and engineering communities.

Role Responsibilities / Accountabilities

  • OT Security Assessment & Risk Management
    • Conduct OT security assessments and risk reviews across the manufacturing sites and divisional OT environments; identify security gaps, assess risk against the Group OT security standard, and produce clear, risk‑prioritised findings with practical remediation recommendations appropriate for the operational context.
    • Support divisional teams in understanding and implementing OT security risk assessments; provide technical guidance on risk assessment methodology appropriate for OT environments, including consequence‑based analysis that accounts for physical safety, process continuity, and environmental implications.
    • Maintain and update the Group OT risk register in collaboration with the OT and Manufacturing Security Manager; track remediation activity against identified risks, monitor progress, and flag where risks are not being addressed within agreed timescales.
  • OT Vulnerability Management
    • Monitor OT‑specific vulnerability intelligence sources and vendor security advisories; assess the applicability and risk of vulnerabilities to the OT estate, and develop practical remediation or mitigation guidance that acknowledges the constraints of OT patching cycles and change management processes.
    • Communicate vulnerability findings and recommended actions to divisional engineering teams and system owners in a form they can understand and act on; track remediation or compensating control implementation through to closure.
    • Support the management of OT‑relevant projects across the Group estate; review project proposals and change requests for security implications, provide technical OT security input to design reviews, and assure that security controls are implemented as intended.
  • OT Monitoring & Claroty Platform Support
    • Support the deployment and ongoing operation of Claroty across the manufacturing sites; configure asset discovery and network monitoring capabilities, validate that the platform is providing accurate and complete OT asset inventory, and ensure that monitoring coverage extends to all in‑scope environments.
    • Manage and review OT security monitoring alerts from Claroty and other OT monitoring tooling; investigate anomalous activity, assess severity and operational impact, and elevate confirmed or suspected incidents to the OT and Manufacturing Security Manager and the SOC in line with the Group incident response process.
    • Support integration of OT monitoring outputs into the Group SOC operational workflow; work with the SOC and Security Platform Engineering Manager to ensure that OT alerts are correctly classified, enriched, and handled by SOC analysts who may have limited OT context.
  • Divisional Engagement & Technical Guidance
    • Engage directly with divisional engineering teams, plant managers, system owners, and BISOs to provide technical OT security guidance and practical support; build trusted working relationships with operational and engineering communities who may have limited prior exposure to cyber security, and develop a reputation as a helpful, knowledgeable, and operationally aware partner.
    • Provide technical review and guidance on OT network architecture, IT/OT segmentation, secure remote access design, and system integration proposals; identify security concerns at the design stage and work constructively with engineering teams to address them without impeding operational delivery.
    • Support the management of OT third‑party relationships; assist in assessing the security posture of OT suppliers, system integrators, and remote maintenance providers, and ensure that access controls, network segmentation, and contractual security requirements are appropriately applied and enforced.
  • Incident Response Support & Crisis Readiness
    • Provide technical OT security expertise in the event of a cyber incident affecting manufacturing or OT environments; support the OT and Manufacturing Security Manager and the Group incident response team with OT‑specific situational awareness, technical analysis, and advice on response options that balance security with operational and safety imperatives.
    • Support the development and maintenance of OT cyber incident response plans and playbooks; contribute to the design of OT‑specific crisis exercises and help ensure that divisional engineering and operations teams are prepared to respond effectively when needed.
  • Awareness, Training & Continuous Improvement
    • Develop and deliver OT‑specific security awareness and training content for operational, engineering, and plant management audiences; create materials that are relevant, accessible, and appropriate for people whose primary expertise is engineering rather than cyber security.
    • Stay current with developments in OT cyber security – emerging threats, vendor advisories, ICS‑CERT publications, regulatory developments – and bring relevant intelligence to the OT and Manufacturing Security Manager in a timely and structured way.

Experience, Knowledge, Skills & Attributes

  • 5+ years in cyber security, with at least 3 years of hands-on experience in OT, ICS, or manufacturing security roles within an industrial or manufacturing organisation.
  • Demonstrable, hands-on experience of real OT environments – SCADA, ICS, PLCs, DCS, or HMI – sufficient to engage credibly with plant engineers and system owners, and to make practical security recommendations that respect operational constraints and safety requirements.
  • Experience conducting OT security assessments or risk reviews, producing structured findings reports, and providing remediation guidance appropriate for the operational context.
  • Experience working directly with OT vulnerability intelligence sources and developing remediation or mitigation guidance that accounts for OT patching constraints and change management requirements.
  • Experience engaging directly with engineering, operations, or plant management teams to deliver security guidance, conduct site assessments, or provide security design input to OT projects.

Knowledge & Skills

  • Solid technical knowledge of OT environments: SCADA, ICS, DCS, PLCs, HMI systems, and OT‑specific protocols including Modbus, OPC‑UA, DNP3, and Profinet; able to interpret architecture diagrams, network designs, and vendor documentation for these environments.
  • Working knowledge of OT security frameworks and standards: IEC 62443, NIST SP 800‑82, and the Purdue Model; understanding of IT/OT network segmentation principles and common secure architecture patterns for OT environments.
  • Understanding of OT asset discovery and network monitoring concepts; familiarity with passive and active monitoring approaches and the considerations for deploying monitoring tools safely in live production environments.
  • Strong interpersonal and communication skills; able to build trust with engineering and operational teams who may be unfamiliar or initially sceptical of cyber security, and to explain technical security concepts clearly to non‑security audiences.
  • Genuine understanding of the safety-security interface: able to design and recommend security measures that do not compromise plant safety, process integrity, or operational availability.

Qualifications

  • Degree‑level education in engineering, computer science, information security, or a related technical discipline; or equivalent professional experience.
  • Professional certification in OT or cyber security: GICSP, ISA/IEC 62443 CCST, CompTIA Security+, or equivalent.

Experience

  • Experience in a large FMCG, food and beverage, sugar, agricultural, or consumer goods manufacturing organisation, with direct exposure to food‑grade, hygiene, or continuous process manufacturing environments.
  • Hands‑on experience deploying or configuring an OT network monitoring or CAASM platform (e.g. Claroty, Dragos, Nozomi Networks) in a live production environment.
  • Experience providing OT security input to a significant manufacturing technology project, OT upgrade, or new site build, including design review and security requirements definition.
  • Experience supporting or participating in an OT cyber security incident response, including real‑time technical analysis and communication to operational stakeholders under pressure.

Knowledge & Skills

  • Familiarity with a specific OT vendor ecosystem relevant to the manufacturing estate (e.g. Siemens, Rockwell Automation, Schneider Electric, ABB, or Honeywell) and the security implications of their platforms and architectures.
  • Understanding of IT/OT convergence considerations arising from IIoT and Industry 4.0 deployments, and awareness of the new attack surfaces these introduce in manufacturing environments.
  • Working knowledge of the broader IT security estate (Microsoft E5, Defender suite, Zscaler) and the considerations that arise when extending IT security controls into OT network zones.
  • Awareness of health, safety, and environmental (HSE) regulatory frameworks as they intersect with OT security, and an appreciation of the physical safety and environmental consequences that can result from cyber incidents in manufacturing environments.

Qualifications

  • ISA/IEC 62443 Cybersecurity Certificate or higher level qualification in OT security.
  • CISSP or CISM for those looking to develop broader security leadership credentials alongside their OT specialism.
  • Membership of a relevant professional body or industry group (CIISec, IET, ISA, BCS) is welcome.

OT Security Specialist employer: ISS

At ISS, we pride ourselves on being a world-leading workplace and facility management company that values people at its core. Our commitment to employee growth is evident through our diverse and inclusive work culture, where every team member has the opportunity to develop their skills and make a meaningful impact. With a focus on service excellence and a strong safety culture, we offer a rewarding environment for Key Account Managers to thrive in, all while contributing to the success of our clients across various sectors.

ISS

Contact Details:

ISS Recruitment Team

StudySmarter Expert Advice🤫

We think this is how you could land OT Security Specialist

Get Involved in the Cybersecurity Community

Diving into the cybersecurity community is key for landing that full-time gig. Join forums like Reddit's r/cybersecurity or attend local meetups to connect with industry veterans and other job seekers. Networking is everything in this field—don’t just be a passive lurker!

Show Off Your Skills with Capture the Flag Competitions

Participate in Capture the Flag (CTF) competitions; these are not just a fun way to boost your skills but also a chance to showcase your talent to potential employers. Many companies, including ISS, love seeing candidates who actively engage in these challenges.

Tailor Your Online Presence

Make sure your LinkedIn and any professional profiles reflect your cybersecurity expertise. Share your projects, whether they’re personal or from a previous role, to catch the eye of hiring managers. This is how they’ll find your passion and commitment to the field!

Apply Directly Through ISS

Don’t forget to head straight to our website and check out any openings for cybersecurity roles at ISS. Applying directly can sometimes give you an edge, especially if you can mention that you've been following our work or engaging in the community.

We think you need these skills to ace OT Security Specialist

OT Security Assessment
Risk Management
Vulnerability Management
SCADA
ICS
PLC
DCS

Some tips for your application 🫡

Show off your technical skills:In cybersecurity, it's crucial to highlight your technical prowess. Make sure your CV showcases specific skills like network security, penetration testing, or threat analysis. If you have relevant certifications (like CEH or CISSP), pop those on the front page to grab attention!

Tailor your portfolio for the role:Even for a full-time role, a portfolio can set you apart. If you've worked on any cybersecurity projects—be it CTF challenges, security assessments, or research papers—include these in your application. This demonstrates not just your skills, but also your hands-on experience!

Use real-world examples:When writing your cover letter, don’t just stick to your qualifications. Share real-world examples of how you’ve tackled security issues or vulnerabilities. This gives the hiring team at ISS insight into your practical problem-solving abilities and makes your application memorable.

Demonstrate your passion for cybersecurity:Cybersecurity is an ever-evolving field, so show us that you’re always learning! Mention any recent courses, webinars, or industry events you’ve attended. This not only exhibits your enthusiasm but also signals to ISS that you’re committed to staying ahead in the game.

How to prepare for a job interview at ISS

Sharpen Your Technical Skills

For a role in cybersecurity, it’s essential to be up-to-date with the latest tools and techniques. Brush up on your knowledge of firewalls, intrusion detection systems, and vulnerability assessment tools. Be ready to discuss specific scenarios where you’ve applied these skills, as hands-on experience can really set us apart in interviews.

Prepare for Scenario-Based Questions

Expect the interviewers at ISS to throw in some hypothetical situations to see how you’d handle them. Think about common security breaches or incidents and be prepared to explain how you would respond. This not only shows your problem-solving skills but also your understanding of real-world cybersecurity challenges.

Highlight Your Certifications

Certifications like CompTIA Security+, CISSP, or CEH can give you a significant edge in a full-time role in cybersecurity. Make sure to mention these during your interview and be prepared to discuss what you learned through those certifications and how they relate to the position at ISS.

Show Your Passion for Cybersecurity

Since you’re going for a full-time gig, showing genuine enthusiasm for the field can make all the difference. Share any personal projects, blogs, or communities you’re part of that relate to cybersecurity. This not only showcases your passion but also your commitment to staying engaged in this ever-evolving field.