SILcet Cloud is a web-based tool for SIL verification of Safety Instrumented Functions (SIF). It follows internationally recognized standards, including IEC 61508, IEC 61511 / ISA84, ISA-TR84.00.02:2022, and widely accepted industry best practices.

It is a modern, cloud-native solution with a user-friendly interface, where all calculations are performed on secure servers. No local installation is required.

The design and development of SILcet Cloud are based on the Excel-based version SILcet Pro Plus, a solid and mature tool used in real engineering projects for many years. Both versions use exactly the same calculation formulas, ensuring technical consistency and continuity.

SILcet Cloud supports both low demand and high demand mode SIFs and addresses the three IEC requirements:

• Systematic Capability
• Probability of Failure (PFDavg / PFH)
• Architectural Constraints

• Allows selection of different architectures for each SIF subsystem.
• Low Demand Mode (PFDavg):
  1oo1, 1oo2, 2oo2, 2oo3, 2oo4, 1oo1D, 1oo2D, 2oo4D, 2oo3D, 1oo3, 1oo4, 1oo5, 3oo3, 4oo4, 5oo5, 6oo6, 3oo4, 3oo5, 4oo5, and MooN (for less common architectures).
• High Demand Mode (PFH):
  1oo1, 1oo2, 2oo2, 2oo3, 2oo4, 1oo1D, 1oo2D, 2oo4D, 2oo3D, 1oo3, 1oo4, 1oo5, 3oo3, 4oo4, 5oo5, 6oo6, 3oo4, 3oo5, 4oo5, and MooN (for less common architectures).
• Allows calculation of complex configurations combining several groups of architectures.
• Each sensor or actuator subsystem can have up to 6 legs, with up to 10 devices per leg. The logic solver subsystem supports up to 8 parts.

The supported architectures are aligned with IEC 61508 / IEC 61511 requirements and reflect real-world industrial implementations, enabling accurate and transparent SIL verification.

• Failure rates of each SIF element (SD, SU, DD, DU), element type (A or B), and systematic capability.
• Cpt (coverage of proof tests), Test Interval (TI), Life Time (LT), Beta factor for common cause failures, MTTRdd (mean time to restore dangerous detected failures), Start-up time (after a spurious trip), and transmitter diagnostic settings.
• Allows entry of previously calculated values of PFDavg, PFH, and MTTFS.
• Optional multiplying factors: each leg and subsystem includes a factor (F or Fsub) to multiply the resulting PFDavg/PFH and STR. By default, these factors are set to 1. They are useful for batch processes or testing.
• Site Factors: allow adjustment of parameters such as failure rates, Cpt, TI, LT, and Beta. These factors are useful for testing, quickly evaluating SIF behavior with higher or lower parameters, or quantifying the effectiveness of SIS maintenance.

All parameters are visible and traceable, ensuring transparency for reviews, audits, and Functional Safety Assessments.

SILcet Cloud provides two types of databases for sensor, actuator, and logic solver subsystems:

• User Database
  Fully flexible. Users can create, modify, and manage their own devices and data according to project needs. Databases can be imported from or exported to Excel.
• SILcet Database (Advanced Plan)
  A comprehensive predefined database including generic devices commonly used in industry, such as transmitters, valves, actuators, and logic solvers.

Both database types are designed to support consistent and repeatable SIL verification.

SILcet Cloud allows the generation of different types of reports in multiple languages, including:

• SIF list reports
• Summary result reports
• Detailed reports with results, charts, architecture diagrams, and data tables

Reports can be generated in PDF or Excel format.

By default, reports are available in English and Spanish. Users can add, in their preferences, a list of translated terms for additional languages and enter free-text fields (such as descriptions, notes, SIF names, and project names) in their preferred language.

When saving a project, all project data is exported to an Excel file. Any project can also be imported from Excel.

This allows users to:

• Enter or review SIF data in Excel
• Import structured data into SILcet Cloud
• Reduce manual entry time and minimize errors, especially in large projects

This feature is particularly useful when Excel is already part of the project workflow.

Note: Requires Microsoft Excel 2013 or later (or compatible software that supports .xlsx files, such as LibreOffice).

These features will be available in the second release.

• Comparison of different SIFs to support engineering decisions
• SIF sensitivity analysis, helping identify which parameters most influence PFDavg, RRF, or PFH when a SIF does not meet its target.