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sbridge
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Safety PLC / ESD

Safety logic with clear engineering boundaries.

Engineer shutdown, permissive, and interlock logic with clear separation between control and safety functions.

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Talks to

Safety PLCESDSCADAField

Operating chain view

1Safety PLC
2ESD
3SCADA
4Field

What we cover

A focused scope before implementation starts.

01

SIS lifecycle per IEC 61511

02

Overfill protection (API 2350 levels 1–3)

03

Fire & gas integration

04

ESD valve actuation & response times

Architecture

Engineered architecture, end-to-end.

1

Layer 4

ERP

Business planning, orders, inventory accounting, billing, and master data.

2

Layer 3

TAS

Loading authorization, bay workflow, driver access, and movement records.

3

Layer 2

SCADA / HMI

Operator visibility, alarm response, process status, and event history.

4

Layer 1

PLC / VFD / Safety PLC

Control execution, pump behavior, valve states, permissives, and trips.

5

Layer 0

Field equipment

The measured reality of product movement, custody transfer, and equipment state.

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Safety PLC and ESD architecture comparing BPCS process control with the independent Safety Instrumented System, showing API 2350 overfill protection, ESD valve actuation, and a simplified cause-and-effect matrix.
Safety architecture — independent SIS per IEC 61511 / API 2350.

Scope and outcomes

What we deliver — and what it changes.

Technical work that keeps safety boundaries explicit.

  • Hazard & risk awareness inputs — contribute to hazard identification and risk reduction requirements.
  • SRS contribution — assist in defining safety requirements for instrumented protective functions.
  • SIS hardware/architecture — 1oo1, 1oo2, 2oo3 configurations selected against required SIL and site constraints.
  • SIL 2/3 typical loops — overfill protection, ESD, fire & gas, and pump shutdown functions.
  • Independent overfill protection (API 2350 levels 1–3) — category A, B, C tank classification with levels-of-concern stack (CH / AOPS / LAHH / LAH / MWL).
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  • ESD valve actuation & response times — verify actuator stroke time, solenoid response, and valve seal integrity.
  • Fire & gas detection logic — detector layout, voting strategy, and integration with ESD and suppression systems.
  • Cause-and-effect matrices — document the relationship between initiating events and protective actions.
  • Proof testing — define test intervals, procedures, and bypass governance aligned with IEC 61511.
  • Bypass governance — managed, time-limited, alarmed bypasses with clear ownership and restoration discipline.
  • Alarm management vs SIF independence (IEC 61511 §11.2) — maintain separation between safety instrumented functions and process alarms.

Honesty band

Sbridge contributes engineering, integration and operational support to clients' Safety Instrumented Systems with reference to IEC 61508, IEC 61511 and API 2350. Functional-safety certification, SIL verification of installed loops, and overall site compliance remain the responsibility of the asset owner, the SIS suppliers and accredited certifying bodies.

Representative scenarios

From projects we have participated in.

West African coastal terminal

Challenge

Multiple handoffs between business orders, loading control, and stock records.

Solution

Map ERP, TAS, and field events into a shared operating-chain view.

Outcome

A clearer path for reconciliation, shift review, and phased modernization.

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Southern African inland depot

Challenge

Lean operations team needed better stock confidence and movement traceability.

Solution

Define BulkStock™ entry points around depot movements and daily controls.

Outcome

A practical roadmap for inventory visibility without replacing every system at once.

Discuss a similar case

Multi-product tank farm

Challenge

Planning decisions depended on disconnected reports and manual checks.

Solution

Model constraints with a digital twin and expose KPI signals for operations.

Outcome

Better scenario review before changes reached live yard operations.

Discuss a similar case

FAQ

Questions to settle before scope hardens.

Safety PLC and ESD references describe engineering scope and lifecycle discipline. Final safety claims require project-specific analysis, validation, and owner approval.

Standards we engineer to:

API MPMS · API 2350 · API RP 14C · IEC 61508 · IEC 61511 · IEC 62443 · IEC 60079 · ATEX · MID · ISO 28000 · NFPA 30 · Shell DEP

Talk to us

Map your operating chain. We will show you where time, money, and traceability are leaking.

A focused discovery call gives you a practical view of the systems, field signals, and operating handoffs that deserve attention first.

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