Access Tunnel Linear Heat Detection – Handpicked Solutions by Eurofyre


Access tunnels are used to connect buildings or facilities for convenient passage of people and equipment. They allow personnel to travel quickly to areas such as mines, tube lines, power stations, construction sites and more. In some cases they are even used to provide quick access to different areas in larger buildings such as medical facilities.

Risks and Challenges

Tunnels of any nature are prone to a number of fire safety risks. Fires in such confined spaces can spread very quickly. This means that potential fires must be identified and dealt with as quickly and efficiently as possible. However, there are also a number of different challenges that make fire detection in access tunnels difficult:

Long and open spaces can create an erratic flow of air. This means that smoke from fires can behave unpredictably, making it difficult to detect.
Underground facilities need active ventilation to ensure that the environment is safe and comfortable. Ventilation systems can also affect the behaviour of smoke and render some detection types ineffective.
Access to tunnels is often limited; this means that maintenance can be difficult, thus requiring a low-maintenance detection solution. It also means that being able to pinpoint the location of a fire is essential in reaching the potential threat in a timely manner.
Tunnels are often very dusty and dirty environments with lots of airborne contaminants. Fumes from vehicles, generators and other equipment can also be present in the air. This means that the chosen detection solution must be unaffected by contaminants in the air.

FyreLine EN54 Fixed Linear Heat Detection

FyreLine EN54 Fixed Linear Heat Detection provides the perfect solution for protecting access tunnels from fire. It uses a heat sensing cable to detect areas where there is excessive heat and raises an alarm once its temperature threshold is reached. It is unaffected by airflow or airborne contaminants and can provide an accurate location of the event that has triggered an alarm. It is easy-to-install, low-maintenance and cost-effective.

FyreLine EN54 is fully approved and certified to the EN54 standard and bears the CE mark, showing that it is approved for use within the European Economic Area (EEA) and complies with the EU’s New Approach Directives.

This means that FyreLine EN54 Fixed Linear Heat Detection can be used if the access tunnel to be protected is governed by the European Commision.


The EN54 standard is a mandatory code that specifies requirements for detection components and alarm systems and allows the free movement of construction products between countries of the European Union. According to the Construction Products Regulation, it is mandatory that fire detection and fire alarm equipment is certified under the EN54 standard by an authorised certification body. 

Please note: to comply with EN54-28, the FyreLine EN54 Fixed Controller, FyreLine EN54 Fixed EOL and FyreLine EN54 Fixed LSZH LHD Cable must be used as a complete system.

Typical Wiring Diagram

Handpicked Products for an Access Tunnel

EN54-28:2016 Linear Heat Detector Controller

The FyreLine EN54 Fixed Controller is a dual zone module capable of monitoring up to two zones of FyreLine EN54 Fixed Linear Heat Detection (LHD) Cable. It monitors the cable for overheat conditions and automatically calculates and displays the distance along the cable to the alarm point when an event is triggered. Each zone of the FyreLine EN54 Fixed controller can operate either independently of each other, or in interlock mode.

EN54-4:1997 Power Supply Unit

The ProFyre range of power supplies employ state-of-the-art switch mode power technology to provide a continuous and reliable source of 24V DC power to meet the technical and legislative requirements of the professional fire detection and alarm industry/installer.

EN54-28:2016 Linear Heat Detection Cable

FyreLine EN54 Fixed Linear Heat Detection Cable is a non-resettable line-type heat detector. It uses fixed temperature detection technology to provide a simple method of sensing changes in temperature. With a temperature rating of either 78°C or 88°C, FyreLine EN54 heat sensing cable is suitable for a wide range of applications and environments.

EN54-28:2016 Linear Heat Detection End of Line

The FyreLine EN54 Fixed End of Line is designed to effectively terminate up to two zones of FyreLine EN54 Fixed Linear Heat Detection Cable in a secure, weatherproof enclosure. It has built-in switches to simulate fault or alarm conditions to allow the system to be fully tested in situ. It is particularly useful for when the system is used in interlock mode to prevent false alarms. In this mode, two fixed LHD cables are run side-by-side and an alarm is only activated on the fire alarm control panel when both cables trigger.

Linear Heat Detection Cable Mounting Clips & Accessories

FyreLine L-Clip

The L-Clip can be used to support FyreLine EN54 Fixed Linear Heat Detection Cable below or above the risk. They are most commonly used on flat mounting surfaces and are available in zintec or stainless steel.

FyreLine Tie Wraps

Cable ties are used to secure the FyreLine linear heat cable to the bracketry.

FyreLine Junction Box

The junction box is a quick and efficient method of interconnecting and joining lengths of FyreLine Linear Heat Sensing Cable. It can also be used as an in-line junction box for the incoming leader cable.

Why Choose Eurofyre?

Complete System Supplier
Eurofyre manufactures and supplies all aspects of fire detection including linear heat detection and its associated products and can provide expert advice and consultation.
Demonstration and Training
We offer demonstrations and expert training on a range of systems, including FyreLine linear heat detection systems, in our very own sophisticated training facility.
After-Sales Support
Eurofyre offers both on-site and telephone support to assist you in ensuring that your system is fully functional and operating at maximum efficiency. Our after-sales care and support are second to none.

For more information about EN54 Fixed Linear Heat Detection, or to discuss any of the other products that Eurofyre has to offer, please feel free to get in touch either by phone on +44 (0) 1329 835 024, by email to [email protected] or via the online enquiry form situated on our contact page.

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