Fire and Smoke Curtains: Enhancing Fire Safety and Building Containment

Fire safety is a critical aspect of building design and construction. One of the key elements in ensuring fire safety is the use of fire curtains. These flexible compartmental devices play a crucial role in reducing the spread of flames and smoke within a building or open space. In this article, we will explore the functionality, types, and performance criteria of fire curtains, as well as their importance in enhancing building safety.

Understanding Fire Curtains

A fire curtain is a flexible barrier that can be installed vertically or horizontally to divide a building or open space into smaller sections. Its primary purpose is to slow down the spread of flames, providing valuable time for people to evacuate and emergency services to intervene. Fire curtains can be manufactured in two main types: standard (single layer) and insulated (multi-layer).

• Standard Fire Curtains: These curtains are designed to stop the spread of flames but are not specifically designed to prevent the spread of smoke. They act as a barrier to contain the fire within a specific area, preventing it from spreading further.
• Insulated Fire Curtains: In addition to stopping the spread of flames, insulated fire curtains also provide insulation from heat. They are designed to reduce the transfer of radiant heat, keeping the non-fire side of the curtain cooler and safer. Insulated fire curtains can be fitted with smoke seals to limit the spread of smoke.

Smoke curtains, on the other hand, are flexible compartmental devices used to reduce the spread of smoke within a building. They are commonly integrated into Smoke and Heat Exhaust Ventilation Systems (SHEV Systems) and are designed to direct smoke into a safe area where it can be extracted from the building.

Categorizing Fire Curtain Performance

Fire curtains are categorized based on three main performance criteria: integrity, radiation, and insulation.

1. Integrity (E): Integrity refers to the ability of the fire curtain to maintain its structural integrity without developing gaps or tears when exposed to heat. Fire curtains are tested in a furnace, where the temperature can exceed 1000°C. The integrity rating indicates the duration for which the curtain remains intact without any surface flaming for more than 10 seconds.
2. Radiation (W): Radiation measures the thermal energy passing through the fire curtain. A radiation rating is determined by placing a probe 1 meter away from the curtain and measuring the energy given off in kW/m2. The curtain must not exceed a certain threshold (usually 15 kW/m2) within a specified time frame to achieve the radiation rating.
3. Insulation (I): Insulation refers to the ability of the fire curtain to maintain a low surface temperature on the non-fire side. Multiple temperature probes are attached to the curtain, and the average surface temperature must not exceed a certain level (typically 140°C) while avoiding hot spots greater than 180°C. Achieving an insulation rating also contributes to reducing radiation.

These performance criteria, denoted by letters followed by numbers, determine the duration for which a fire curtain has been successfully tested. For example, ratings such as 15/30/60/90/120/180/240 indicate the minutes for which the curtain has passed the corresponding performance criteria.

Materials and Testing Standards

To ensure the effectiveness and safety of fire curtains, the materials used in their construction undergo rigorous testing. Two main standards commonly applied are BS 476-1 and BS EN 13501-1.

• BS 476-1: This standard consists of various parts that assess different properties related to the reaction of fire. Parts 6, 7, 12, 20, and 22 are particularly relevant to fire curtains. Part 6 focuses on fire propagation, while Part 7 assesses the spread of flame. Parts 20 and 22 pertain to fire resistance in load-bearing and non-load-bearing elements of construction, respectively. Achieving Class 0 or Class 1 fire ratings requires compliance with these standards.
• BS EN 13501-1: This standard evaluates the fire behaviour of materials based on their combustibility, calorific value, spread of flame, smoke release, and smoke density. It classifies materials into categories such as A1 (non-combustible) and F (no determined performance) for fire behaviour, S1 to S3 for smoke production, and D0 to D2 for flaming droplets.
• BS 8524: This standard outlines the requirements for active fire curtain assemblies used as a fire-resisting barrier in buildings. This standard covers various aspects of fire curtains, including their design, performance, installation, and maintenance. The standard ensures that these fire safety products meet specific criteria to effectively contain and control fire incidents. Compliance with BS 8524 is crucial for ensuring the safety of occupants and minimizing property damage in the event of a fire.

Meeting these testing standards ensures that fire curtains meet the necessary safety requirements for use in buildings.

THS Industrial Textiles: The Pioneers in Fire Curtain Fabrics

THS Industrial Textiles Ltd, a leading manufacturer in the industry, has been weaving fabrics since 1985. Originally specializing in glass fibre products for composites, THS expanded its offerings to cater to various markets, including fire safety. With extensive experience in weaving and coating fabrics, THS developed a range of specialized fire curtain fabrics.

The core of any smoke or fire curtain is the base fabric, which is meticulously designed and manufactured by THS. However, it is the specialized coatings developed through extensive research and development that enable THS fabrics to compete with the best in the market. These coatings, such as FR Polymer, Intumescent, vermiculite, and Silicone compounds, are applied to achieve different fire ratings, ranging from 60 to 240 minutes of certified integrity.

THS's highest achieving fabric for fire curtains has demonstrated remarkable performance, maintaining its integrity for an impressive 240 minutes (4 hours) in a test furnace with temperatures exceeding 1000°C. This exceptional durability and resistance make THS fire curtain fabrics an ideal choice for applications where stringent fire safety requirements must be met.

Conclusion

Fire curtains play a crucial role in enhancing fire safety and building containment. By effectively dividing a building or open space, these flexible compartmental devices slow down the spread of flames and smoke, providing valuable time for evacuation and intervention. Fire curtains are categorized based on their integrity, radiation, and insulation performance criteria, ensuring their ability to withstand fire and protect occupants.

THS Industrial Textiles Ltd, with expertise in weaving and coating fabrics, has become a pioneer in manufacturing specialized fire curtain fabrics. These fabrics, coupled with innovative coatings, offer exceptional durability and fire resistance. By adhering to rigorous testing standards, THS ensures that its fire curtains meet the necessary safety requirements and contribute to the overall fire safety of buildings.

Investing in fire curtains is an essential step in creating a safe and secure environment. With THS Industrial Textiles leading the way in fabric manufacturing, building owners and occupants can have peace of mind knowing that their fire safety needs are met with the highest quality products.

For more information about THS Industrial Textiles and our range of fire curtain fabrics, visit our website at www.thstextiles.co.uk.