The COSS (Controller of Site Safety) Initial Course is structured into 12 sessions, each designed to progressively build the knowledge and skills required for safe and effective site management on the railway. The first session covers domestic arrangements and check-in, familiarizing learners with the course structure and behavioural expectations, followed by the introduction of course assessments. This ensures delegates understand both the practical and professional standards they need to meet.

In Session 2, learners dive into the role of the COSS, focusing on the technical aspects outlined in the GERT8000 Rule Book Handbook 7. This session covers leadership qualities, the application of Network Rail Lifesaving Rules, and the duty of care that a COSS must uphold. Learners also explore the Fair Culture Flowchart, which guides decision-making in safety-critical situations.

Session 3 addresses fitness for duty and introduces the Sentinel application, teaching learners how to verify certifications and assess fitness to work. This session reinforces the importance of a safety culture that encourages challenging unsafe behaviour.

In Session 4, learners explore planning for protection, examining how to create and verify Safe Work Packs (SWP) and Incident Response Packs (IRP). They gain insight into the roles of the Person in Charge (PIC) and the Rail Incident Officer (RIO), emphasizing collaboration in planning safe systems of work.

Session 5 focuses on understanding your site, teaching learners how to gather information on the worksite using resources like sectional appendix line diagrams and Weekly Operating Notices (WON). This session also emphasizes the difference between hazard and risk and covers legal responsibilities for health and safety.

The next critical session, Session 6, teaches the methods of protection. Learners examine safeguarded systems, line blockages, and additional protection methods. They practice using Track Circuit Operating Devices (T-COD) and Signal Post Replacement Switches (SPRS), while mastering the ABC-P communication model for clear, safety-critical communication.

Session 7 covers the methods of warning, where learners are introduced to different track warning systems, including train-activated and human-activated systems, as well as unassisted lookouts.

In Session 8, learners delve into the importance of COSS safety briefings, practicing how to deliver effective safety briefings and manage handovers between outgoing and incoming COSS staff.

Session 9 focuses on the role of the COSS working alone, ensuring that learners understand the tasks and protection methods applicable when operating without a team.

Session 10 covers possessions and the role of the PICOS, teaching learners how to manage possessions, set up worksites, and ensure safety within possession zones.

In Session 11, the course moves on to hand trolley management and the line clear verification process, teaching learners the theory of hand trolley use and how to manage vehicle forms and line clear verification.

The final session, Session 12, brings it all together with assessments. Learners complete both practical and knowledge-based assessments to confirm their competence in their role as a COSS.

Each session builds on the last, providing learners with the knowledge, skills, and leadership abilities they need to manage site safety effectively and ensure the well-being of their team on the railway.