Queries have been put forth on Safety Assurances on Railway Metro System as a whole as well as on sub system or part thereof. All system must be individually as well as collectively be safety compliant and for its true realization common understanding is must among all stakeholders in general and providers in particular.
To begin with; out of labyrinths of Standards, Code, Rules & Regulations, objective of any system application as a solution to the specific issue must be kept in mind like Rolling Stock ‘to move’ ;traction power ‘to energize’ ,Signalling ‘to Signal ‘ and so on so forth. Throughout the journey of Safety Assurance activities; it will be the beacon light.
For example; take the case of Tunnel Ventilation System (TVS). Objective of TVS is to keep ventilation sustainable for passenger carrying train.
Now Tunnel has different environment than elevated or at-grade/on-ground route. For provisioning of TVS; some specific equipments are required in specific configuration to provide desired results.
Now ‘Requirements’ moves from Objective to Concept to Technical and Non- Technical level solutions. Technical level solutions shall be addressed through design, manufacturing and configuration complying with certain standards; Rules and Regulations etc. Non-Technical /administrative/executive level solutions shall be in compliance to certain Standards, Rules and Regulations etc.
It must be bear in mind that Life Cycle phase till commissioning goes through application of various Standards ,codes, rules and regulations and best practices of the domain; and here comes scrutiny of processes and products as well as people (Human Resources ) associated with it.
‘Architecture of the solution’ should be mapped in non-technical manner (like Block Diagrammed or Flow-Charted on Objectivities) and safety specifics under specified conditions should be verified and validated.
While undertaking Safety assurances; restrain/refrain from technical scrutiny and restrict to parameters related to Safety. Discussion should predominantly be restricted to Safety aspects care in design, development; and technical team to be requested to reassurance themselves and confirm suitable application and compliance of required Standards, Codes, and Rules & Regulations.
It is worthwhile to appreciate that Safety Assurance must be evaluated, verified and Validated in modular manners. Like in case of TVS; each Underground section and Stations may have different lay out and or configuration of equipments; and if so , each section and stations individually as well as collectively be verified and validated for safety assurance. For specific SIL assessment; electronics must be identified in the whole of architecture and focused upon specifically.
For Railway Metro system Safety Assurance; each System should be subjected to Safety Assurances scrutiny including its interfaces and integrations.