Guide To Passive Fire Protection Systems for Industrial Use

In industrial environments, a fire rarely stays small for long. Large internal volumes, high fire loads, complex routes and frequent layout changes (lines, ducts, cables, machines) increase the chance of fire and smoke spreading rapidly.

To give you an idea, in England, fire and rescue services attended 38,468 building fires in the year ending March 2025. That is why passive fire protection is so important. Its purpose is not to extinguish flames, but to slow the spread of fire and smoke.

Passive fire protection systems work without any human intervention or external energy input. These systems are designed to protect occupants by containing fire and smoke within a single room or area, utilising fire-resistant walls, floors, and doors. This compartmentalisation provides more time for safe evacuation and helps reduce damage.

This creates an essential window of time for safe evacuation, for active protection to function, and for emergency services to act more effectively. This guide explains how passive protection works in industrial operations, which systems are most common, and how to align your strategy with applicable requirements and guidelines.

What is passive fire protection?

Passive fire protection is a set of solutions incorporated into a building that helps contain fire, heat and smoke in a specific area for a certain period of time. Examples include fire-resistant walls, floors, and doors, which compartmentalise the building and help contain fire and smoke. In general, it relies on fire-resistant materials and elements and is a key concept for any safety strategy.

Compartmentalisation divides the building into areas capable of limiting the spread of fire. Fire-resistant walls and floors are built with materials designed to resist the spread of fire, making these fire protection measures essential for building safety.

The Fire Protection Association describes passive protection as a fundamental part of fire safety precisely because it works through containment and compartmentalisation. Implementing passive fire protection is a legal requirement in many regions, including under Building Regulations in England (and equivalent requirements elsewhere in the UK), and robust, certified PFP may lower insurance costs.

In an industrial plant, this extra time helps reduce the risk of fire reaching escape routes, critical areas such as electrical rooms, compressors and control rooms, and structures that, if compromised, can cause serious operational and financial losses.

Active protection vs. passive protection: Why the two need to be aligned

Active protection is the set of measures that detect, alert and/or fight fire, such as alarms, smoke and heat detectors, sprinkler systems and fire alarm systems. These active fire protection measures detect heat or smoke and initiate a process to protect occupants and property.

Active and passive fire protection are different forms that collectively contribute to overall fire safety, and both are essential for protecting buildings and occupants.

Active fire protection systems are extremely important because they take immediate action to extinguish or control fires, either automatically or with human intervention. Passive protection, on the other hand, works to limit the spread of fire within the building and preserve the integrity of essential parts for longer.

The two layers complement each other. Active fire protection systems require a process of detection and response, often involving human intervention, while passive systems work without it. An efficient alarm system can alert quickly, but if smoke passes through compartments because of an unsealed passage, escape routes become compromised sooner than they should.

Similarly, a fire door that does not close, or a damper that is inaccessible for inspection, undermines systems designed to work even without immediate human action. Both systems play a crucial role in protecting property and saving lives.

What the UK requires: Overview for industrial sites

In the United Kingdom, there is a legal duty to manage fire risk on-site, and the basis for this is a risk assessment. In England and Wales, the Regulatory Reform (Fire Safety) Order 2005 sets out obligations and requires a fire risk assessment to be carried out that is appropriate to the context of the building.

A Home Office guide emphasises that the risk assessment should guide proportionate measures and that the competence of those who assess, implement and maintain the measures makes a real difference to the level of safety achieved. Passive fire protection systems must also be maintained to be effective and compliant with legal requirements.

When it comes to new construction, extension or major renovation in England, Approved Document B (Volume 2) is an important reference for fire safety requirements in non-residential buildings. It is updated periodically and guides how to meet performance requirements in design and execution.

Scotland and Northern Ireland have their own legislation and specific guides. If the operation is multi-site, it is prudent to treat the issue as part of governance and compliance, and not just as a construction project.

How passive protection works in practice in industrial environments

A good passive protection system clearly defines where fire and smoke should not pass. This is achieved through well-designed compartments, controlled openings and the elimination of unplanned shortcuts, especially in shafts, technical ceilings and facility passageways.

Compartment walls are critical barriers in passive fire protection measures, and regular inspection and sealing of any gaps or breaches are essential to prevent the spread of fire and smoke.

At industrial sites, the challenge is rarely just designing and installing. It is maintaining the integrity of the system over time, even with constant changes. Therefore, actual performance depends as much on design as it does on operational discipline. Any intervention that crosses a fire-resistant wall or slab must be treated as a risk and corrected appropriately.

Most common passive protection systems in industry

Compartmentalisation and fire-resistant elements

Compartmentalisation is the basis of passive protection. It separates risk areas to limit the spread and preserve escape routes. In industrial plants, this tends to be especially important between production, storage, utility, electrical rooms, and administrative areas. What usually compromises compartmentalisation, however, is not the wall itself, but rather the openings and layout changes that arise over time.

Fire doors and smoke control

Fire doors are part of the compartmentalisation strategy and, in many locations, are also essential for maintaining protected routes. Emergency escape lighting supports safe evacuation, but it is not part of passive fire protection. It illuminates escape routes and helps occupants evacuate safely during a fire.

In industrial environments, recurring problems arise when doors are kept open for convenience, when they are damaged by heavy traffic (trolleys, pallet trucks, forklifts) or when components are replaced without compatibility with the assembly. The consequence is that the door fails to fulfil its role exactly when it matters most.

Fire stopping

In industry, virtually everything passes through compartments: cables, ducts, pipes, and instrumentation. If these penetrations are not sealed properly, smoke finds quick paths, and fire can jump barriers.

It is crucial to inspect compartment walls for breaches and ensure all gaps are properly sealed, as any compromise in these critical barriers can undermine the effectiveness of passive fire protection systems.

Sealing needs to be treated as a methodical and traceable system, not as an improvised solution. This is a point that, because it is often in hidden areas, tends to go unnoticed until a more rigorous inspection reveals flaws.

Fire and smoke dampers in ventilation ducts

Ducts can be one of the most efficient ways for smoke and heat to spread between compartments. Therefore, dampers (fire and smoke) are a critical measure when ventilation systems cross fire-resistant barriers.

Fire dampers are installed in HVAC systems to prevent the spread of fire through ducts and are designed to close automatically when triggered (typically by heat). Automatic vents can also be used in ventilation systems to improve smoke clearance and facilitate occupant evacuation during a fire.

In the UK, BESA’s DW/145 is often cited as an industry benchmark for good practice in the installation and maintenance of these devices, and effectiveness depends heavily on accessibility, inspection and documentation.

LJM Fire Solutions offers damper inspection and maintenance services in line with industry benchmarks, which makes sense in industrial environments where evidence and maintenance discipline are critical.

Fire curtains and large spans

At industrial sites with large spans, docks, wide passageways or operational requirements for open space, fire curtains can be an alternative for creating barriers when necessary. As these are systems that operate in the event of an incident, they require special attention to testing and maintenance in accordance with the design and manufacturer’s specifications. LJM also works with this type of solution in the UK.

Structural protection with intumescent materials

When the strategy requires structural elements to maintain their load-bearing capacity for a specified period of time when exposed to fire, solutions such as intumescent steel coatings come into play.

Intumescent fireproofing is a protective coating applied to structural steel that expands when exposed to high temperatures, enhancing fire resistance and helping the steel maintain its structural integrity during a fire. In industry, this can be decisive in exposed structures, mezzanines, walkways and areas where collapse would cause chain reactions, affecting safety and operational continuity.

Inspection, maintenance and change management: How to keep the PFP alive

In industry, the question is not only whether the system has been installed correctly, but whether it remains intact after months of interventions. A small hole made by a third-party team can compromise a fire-resistant wall. A door that is not properly adjusted may fail to close. A damper without access becomes a blind spot.

That is why change management is crucial. Every change that crosses fire-resistant barriers should be identified, assessed, and corrected methodically. Competence and continuous control are important for safety measures to remain effective, especially when third parties and specialised activities are involved.

Why choose LJM?

At LJM Fire Solutions we bring over 40 years’ experience in fire protection across industrial and commercial environments. We understand passive fire protection is not just about installation, it is about lasting performance, compliance and peace of mind on complex sites. Our engineers are directly employed, fully trained and up to date with current British Standards and legislative requirements, so you get technically sound solutions and practical advice that align with your risk profile and regulatory duties.

We provide tailored support from survey and design through to installation, maintenance and repair across a wide range of fire safety systems including fire dampers, fire curtains and suppression systems. Working with us means having a single point of contact for comprehensive fire protection, helping reduce fragmentation and improve ongoing compliance and inspection records.

Our local presence in the North East means we can respond promptly when you need us, and our customer-centric approach means we work closely with you to fit services to your operational needs and priorities. Choosing LJM gives you demonstrable competence, a structured programme of checks and maintenance, and a team that understands how critical passive fire protection integrity is to safety and business continuity.

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Conclusion

At industrial sites, passive protection is what transforms a potentially devastating fire into a more contained event, with more time for evacuation and response. Compartmentalisation, fire doors, penetration sealing, dampers in ventilation systems, fire curtains and structural protection can be combined to reduce the spread of fire and smoke and preserve the integrity of the building.

The key point, however, is consistency over time. Layout changes, new installations, and routine interventions are common in the industry, and each of these can compromise fire-resistant barriers if there is no evidence-based change management, inspection, and maintenance.