At Meritas, we often find ourselves explaining that the most critical components of a building’s safety strategy are usually the ones that occupants never see.

While the general public is well-acquainted with the sight of fire extinguishers or the sound of a fire alarm, there is an entire world of passive and active protection working silently within the ceiling voids and ventilation shafts.

Fire dampers and smoke control dampers are essential life-safety components, specifically engineered to support a building’s fire strategy and ensure that every structure remains a safe environment for its inhabitants.

Our work is governed by a complex framework of UK legislation, building regulations, and British Standards, all of which have evolved significantly to meet the demands of modern architectural design. We view these devices not just as mechanical fittings, but as a robust first line of defence that prevents a localised fire from escalating into a catastrophic event.

Understanding Compartmentation: The Foundation of UK Fire Safety

The fundamental principle that underpins our approach at Meritas is compartmentation, a core tenet of UK fire safety design that divides a building into manageable zones.

By using fire-resistant walls, floors, and ceilings, we can ensure that a fire is contained within its area of origin, providing vital time for evacuation and firefighting operations. However, modern buildings require extensive heating, ventilation, and air conditioning (HVAC) systems to maintain air quality and comfort, which necessitates cutting holes through these fire-resistant barriers.

This is where fire dampers become indispensable; they are passive fire-protection devices installed at the exact point where ductwork penetrates a fire-resisting element. Their primary mission is to restore the integrity of that barrier the moment a fire is detected, ensuring that the ventilation system does not become a path for flames to spread throughout the property.

The Mechanical Ingenuity of Passive Fire Dampers

One of the most impressive aspects of a standard fire damper is its simplicity and reliability, operating entirely without the need for an external power supply.

These mechanical devices are typically held in an open position by a thermal release mechanism, most commonly a fusible link. This link is precision-engineered to melt or break when it is exposed to a specific temperature rise, normally 72c.

When the heat from a fire reaches this threshold, the link fails, allowing the damper blades to automatically spring shut and create a solid physical barrier.

 This passive operation is critical because it ensures the damper will function even if the building’s electrical systems have failed during an emergency. To guarantee this performance, every fire damper we work with must be tested and classified to BS EN 1366-2, a rigorous furnace-testing standard that simulates the extreme conditions of a real fire.

Navigating the New Era of Building Safety

The landscape of our industry changed fundamentally on the 28th of April 2022, when the Building Safety Act received royal assent.

This legislation was a direct response to the tragic events at Grenfell in 2017 and has introduced a new era of accountability and oversight for everyone involved in the construction and management of higher-risk buildings.

At Meritas, we take the Act’s emphasis on “industry competence” very seriously, as it requires that every individual working on these systems possess the specific skills, knowledge, and experience necessary to ensure life safety. The regulations now demand far more transparency, including the meticulous inspection and testing of all services, fittings, and equipment provided in connection with a building’s fire strategy.

This means that the installation and maintenance of fire dampers are no longer just routine tasks but are now part of a strictly regulated chain of responsibility designed to protect the public.

Active Smoke Management: The Role of Smoke control dampers

While fire dampers are passive guardians against flames, smoke control dampers are active safety devices that form a vital part of a building’s smoke control strategy. Smoke is widely recognised as the single greatest risk to life during a fire, as it can travel much faster than heat and quickly obscure escape routes.

Smoke control dampers are fitted with electric actuators and are integrated into the building’s fire alarm system or a dedicated smoke control panel. Unlike their passive counterparts, these devices are triggered by smoke detection rather than heat, allowing them to activate much earlier in a fire’s development.

They are designed to control the movement of smoke, either by closing to protect stairwells and lobbies or by opening to assist mechanical extraction systems in clearing toxic gases from the building. These systems must be tested to BS EN 1366-10 to ensure they can operate reliably under the pressure and temperature differentials present during a real incident.

Sophisticated Airflow: AOVs and Mechanical Extract Systems

A comprehensive fire safety strategy often involves natural ventilation solutions, specifically Automatic Opening Vents, or AOVs.

These are essential components of natural smoke ventilation systems, often appearing as roof-mounted vents, vertical smoke shafts, or even automatically opening windows. When smoke is detected, a signal from the fire alarm triggers the AOV control panel, causing the vents to open and allowing hot gases to discharge naturally from the building.

This process keeps escape routes clear and tenable for occupants while providing better visibility for the fire and rescue services. For more complex structures, we may implement mechanical extract systems, which use powerful fans to pull smoke out of the building. These systems are highly coordinated; the floor where the fire is located will have its vents open for extraction, while all other floors “lock out” in the closed position to prevent the smoke from spreading through the ducting.

In high-rise buildings and firefighting shafts, we often deploy pressurisation systems to maintain the safety of protected escape routes.

These systems work by supplying a constant flow of air into stairwells and lobbies, creating a high-pressure zone that prevents smoke from entering even if a door is opened. These are balanced systems that use sensors to detect pressure losses; if a lobby door is opened, the fans will automatically “ramp up” to maintain the required pressure differential. We also design specialist systems for basements and underground car parks, where the lack of natural ventilation poses a unique challenge.

These dual-purpose systems often have a “day-to-day” mode for extracting carbon monoxide emissions and an emergency “fire control” mode that ramps up for rapid smoke clearance. All of these sophisticated airflow strategies fall under the multi-part BS EN 12101 standard, which covers everything from the dampers and fans to the power supplies that keep them running.

The Science of Smoke Curtains and Barriers

In large, open-plan environments like shopping centres or airports, traditional walls are often not feasible, which is where fire and smoke curtains become essential. Fire curtains are designed to descend fully during a fire to protect areas like stairwells or lift shafts, and they typically operate with an independent control panel and battery backup to ensure fail-safe performance.

Smoke curtains serve a slightly different purpose; they may only descend 25% of the distance to the floor because they are designed to act as baffles that prevent smoke from spreading horizontally across different zones. Both systems must comply with BS 8524 Parts 1 and 2, which require rigorous third-party certification and extensive testing to ensure they can restrict the spread of smoke effectively.

These curtains are often governed by the building’s fire alarm system and must be integrated into the wider smoke control logic to be effective.

The Meritas Framework for Safety Management

At Meritas, our philosophy is guided by the principles of BS 9999, the code of practice for fire safety in the design and management of buildings. This standard emphasises four key concepts that we integrate into every project: risk management, proportionality, permanence, and the necessity of fire risk assessments.

Risk management involves being proactive in identifying hazards before they can cause harm, while proportionality ensures that the fire safety measures, we implement are appropriate for the specific risk level of the building.

Permanence is about creating safety structures that remain functional and reliable for the entire lifespan of the building, reducing the need for expensive restorations later on. By adhering to these principles and the recommendations of BS 9999, we ensure that our clients’ projects meet the most stringent fire safety standards while contributing to a safer and more sustainable built environment.

The Lifetime Commitment: Maintenance and Legal Compliance

The most sophisticated fire damper in the world is useless if it fails to close when it is needed most. This is why UK fire safety legislation, particularly the Regulatory Reform (Fire Safety) Order 2005, places a significant legal duty on the “Responsible Person” to ensure that all fire-safety systems are properly maintained.

For fire dampers, BS 9999 dictates a mandatory inspection and testing schedule, typically requiring a full check at least every two years, with more frequent annual testing required in high-risk environments like hospitals. Motorised smoke dampers and AOV systems require even more frequent functional testing to verify that actuators, signal responses, and system integrations are working perfectly.

We verify that vents open to the required angle, that actuators have the power they need, and that every component will fail-safe in the event of a power loss. Maintenance is not just a box-ticking exercise; it is a vital part of life safety that ensures the building remains compliant and its occupants remain protected.

Ensuring a Safer Built Environment

Ultimately, fire dampers and smoke control dampers fulfil different but entirely complementary roles within the architecture of a safe building.

Fire dampers preserve the physical compartmentation of the structure in accordance with Approved Document B, while smoke control dampers support complex smoke control strategies under BS 9999 and BS EN 12101. At Meritas, our mission is to ensure that the correct systems are specified, installed, and maintained to the highest possible standard. From the mechanical simplicity of a 72°C fusible link to the complex logic of a extract/pressurisation system, every detail matters when lives are on the line.

We are dedicated to providing the expertise and oversight necessary to navigate this challenging regulatory landscape, ensuring that your building’s first line of defence is always ready to perform.