Linear Heat Detection (LHD) Applications

Often referred to as line type heat detection, LHD is a cable-based type of early fire detection, designed to generate either an alarm, or automatically activate a fire suppression system.

Coated in different materials to suit specific applications, LHD cables are appropriate for use in the majority of dirty, dusty and hard to maintain environments – including damp, humid and unforgiving conditions. This is because they are unaffected by airflow, dangerous chemicals or toxins, removing the risk of reactive failure and false alarms – potentially leading to huge cost (and time) savings.

Built on a solid foundation of over 6 decades of research and development, engineering prowess and technical ingenuity, Thermocable has developed a full range of LHD cables and interface modules that provide continuous coverage, are easy to install and fully integrate with building management systems.

Our products have been certified by globally recognised test houses to ensure they meet the required safety and quality requirements in the industry – giving you complete peace of mind.

As the global leader in LHD technology and manufacturing, Thermocable’s ProReact range provides innovative, cost effective solutions to multidisciplinary industries, including:


This covers all facets of power generation and distribution. From solar and hydrogen, through to High Voltage/Medium Voltage transformers, switch gear and electrical, and power/transmission tunnels.

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Oil and Gas

LHD is ideal for protecting critical infrastructure in upstream, midstream and downstream processes. Often coupled with a high-level suppression system, LHD is fundamental in improving safety efficiency within this sector, especially for floating and fixed roof storage tanks.

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From car parks to kitchens, LHD is frequently used within major infrastructure applications, such as cold storage, escalators, road and access tunnels, server rooms, ceiling voids, cable trays and rail/metro stations.

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Particularly useful in environmentally challenging, hazardous and access restricted areas, LHD is perfect for use in control panels, conveyor belts, waste recycling, distilleries, and ships/marine applications.

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Benefits of working with Thermocable Flexible Elements Ltd

  • World leading manufacturer of cable based sensing and detection technologies based in the UK
  • We continually generate new ideas to bring best leading edge products to market
  • Our vertically integrated lean approach through design, development and manufacturing processes provides reassurance of a flexible and responsive approach to our customer needs and speed to market
  • Our experienced and technically competent team delivers an innovative approach to product development and emerging markets
  • Internationally qualified category solutions provider