FEED Engineering & Conceptual Design

The decisions that determine whether a safety system will work are made before anything is procured. Detector technology, coverage philosophy, integrity level, architecture, independence of the safety layer from the control layer — these are settled at front-end engineering, and changing them later costs an order of magnitude more.

ZE-Tronics provides FEED and conceptual design for fire and gas detection and suppression systems, so the capital decision your board approves rests on a defined risk boundary rather than a vendor’s standard offering.

What FEED delivers

Risk boundary definition. What are we protecting, from what, and to what consequence threshold? This sounds obvious and is routinely skipped. Without an explicit boundary, scope grows quietly through detailed design and nobody can say when protection is sufficient.

Hazard identification. Systematic identification of credible release scenarios, ignition sources and escalation paths — normally through HAZOP, with the fire and gas implications extracted specifically rather than left as an action item.

Consequence modelling. Dispersion behaviour of the specific gases present, under the ventilation and prevailing wind conditions of the actual site. Generic assumptions produce generic detector layouts, and generic layouts miss real releases.

SIL determination. Using LOPA or risk graph methodology per IEC 61511, establishing the required Safety Integrity Level for each safety instrumented function. This number drives architecture, redundancy, proof-test interval and cost. Getting it wrong in either direction is expensive: too low is unsafe, too high wastes capital permanently.

Technology selection. Choosing between catalytic and infrared, point and open-path, UV/IR and multi-spectrum IR — on the basis of the gases present, the environment, false-alarm tolerance and the maintenance regime the site can realistically sustain.

Fire and gas mapping. Geographic and scenario-based coverage assessment per ISA TR84.00.07, producing a defensible statement of what percentage of credible releases the proposed layout will actually detect.

Deliverables

• Safety concept / fire and gas philosophy document
• Hazard identification register with fire and gas actions
• SIL determination report with LOPA worksheets
• Fire and gas detector mapping study with coverage percentages
• Technology selection basis and justification
• Preliminary cause-and-effect philosophy
• System architecture block diagram
• Preliminary equipment list and budget estimate
• Basis of design for the detailed engineering phase

Why the front end is where the money is

An operator who discovers at commissioning that detector coverage is inadequate has three options, all bad: accept the risk, retrofit at full cost during live operation, or delay startup. An operator who over-specifies to SIL 3 where SIL 2 was justified pays for redundant hardware, more frequent proof testing and higher spares holding for the entire asset life.

The proportion of total project cost spent on FEED is small. The proportion of total project outcome determined by it is not.

How we work with your team

1. Data gathering — process documentation, plot plans, existing hazard studies, incident history, operating philosophy
2. Site familiarisation — for brownfield work, physical walkdown. Drawings and reality diverge
3. Workshop facilitation — HAZOP and LOPA sessions with your operations, process, HSE and maintenance representatives
4. Analysis and modelling — dispersion behaviour, coverage mapping, SIL calculation
5. Concept development — technology selection and architecture, with options and trade-offs stated explicitly
6. Review and issue — deliverables issued for your review and third-party verification if required

Frequently asked questions

We already have a HAZOP. Do we need a separate SIL study?
Usually yes. A HAZOP identifies hazards and existing safeguards; it does not establish the required integrity of the instrumented protective functions. IEC 61511 expects SIL determination as a distinct step, and auditors treat it that way.

Can you review a FEED package produced by someone else?
Yes. Independent review of an existing safety concept is a common engagement, particularly before a project passes a stage gate.

What if the site already exists?
Brownfield safety concept work is the more common case. The process is the same, but existing cable routes, available panel space and shutdown windows become design inputs rather than free variables.