Fire Detection in Cold Storage: Risks, Challenges and Why Linear Heat Detection (LHD) Performs in Sub-Zero Environments

Cold storage facilities are among the most technically demanding environments for fire detection. Designed to preserve temperature-sensitive goods, these facilities operate under sub-zero conditions that can impair conventional detection systems and delay early warning.

As cold chain logistics expand globally, driven by pharmaceutical distribution, frozen food supply, and high-bay automated warehousing, the consequence of fire in cold storage is becoming more severe.

This article explores the fire risks specific to cold storage and explains why Linear Heat Detection (LHD) offers a more resilient, reliable approach to early fire detection in sub-zero environments.

The Rising Consequence of Fire in Cold Storage

Cold storage has become one of the most critical and vulnerable links in the global supply chain. Demand continues to rise as consumers expect year-round access to frozen goods, rapid online grocery fulfilment, and the safe handling of temperature-sensitive pharmaceuticals and biologics. 

These facilities operate under extreme, tightly controlled conditions to preserve products. However, this same precision creates fragility. When a fire breaks out in a cold store, the consequences can escalate rapidly, often before early warning systems respond. 

The impact extends far beyond stock loss. Operators face structural damage, and prolonged business interruption, and in some cases, tragic loss of life. A 2024 fire at a cold storage facility in eastern China which claimed nine lives, starkly illustrates the human and operational cost of delayed detection. Devastating events like these show the scale of cold storage fire risks and reinforce the need for robust fire protection measures. 

As facilities increase in scale and throughput, the tolerance for detection failure decreaes significantly. 

Early, reliable detection is therefore critical - not optional.

Common Fire Risks in Cold Storage Environments

Cold storage facilities face several fire risks that behave differently from those in conventional warehouses. These risks often develop in concealed spaces or under low-visibility, sub-zero conditions, making early detection more challenging. Key risks include:

• High-bay racking: Dense, multi-level storage can conceal early within aisles, allowing fires to develop before conventional detectors register heat.
• Plant rooms: Compressors, electrical switchgear, and control panels introduce overheating risks in low-occupancy areas.
• Conveyors and automation: Motor loads, friction points, and jammed belts can create smouldering fires that develop undetected.
• Insulated sandwich panels: Certain panel constructions can promote rapid fire spread within concealed cavities.
• Environmental conditions: Freezing temperatures, condensation, airflow and stratification can impair smoke and point detectors, delaying alarm activation.

These conditions reinforce the need for specialist detection systems engineered specifically for cold storage performance.

Why Conventional Fire Detection Struggles in Sub-Zero Facilities

Traditional smoke and ceiling-mounted detectors rely on predictable fire behaviour. In cold storage, that behaviour is disrupted and three core challenges define the fire detection landscape in cold storage facilities:

1. Harsh Environmental Conditions: Freezer rooms typically operate well below the temperature limits of many point-type smoke and heat detectors. Sub-zero temperatures can reduce sensor sensitivity, cause condensation and ice formation, and increase component stress. False alarms or delayed activation occur as a result..
2. Airflow and Stratification Effects: Cold stores rely on powerful evaporator fans to maintain stable temperatures. This constant airflow can disperse heat and smoke away from detectors, masking the earliest signs of fire. At the same time, temperature layering prevents heat from rising uniformly, preventing ceiling-mounted detectors from triggering until the fire has already intensified.
3. Hidden or Hard to Reach Ignition Points: Many cold storage fires begin in areas that are inherently difficult to monitor, including deep within high-bay racking, inside insulated sandwich panels, behind conveyor and automated systems, and within plant rooms. Ignition in these concealed locations often develops unnoticed until it becomes a much larger fire.

The Solution – ProReact Linear Heat Detection

Thermocable’s ProReact Linear Heat Detection (LHD) systems are engineered specifically for harsh cold storage environments, delivering continuous heat sensing along the entire length of the cable, enabling detection at or near the source of ignition. Designed to integrate seamlessly with conventional and addressable fire alarm systems, ProReact LHD provides a scalable detection solution suitable for a wide range of cold storage layouts and risk profiles.

Rather than relying on isolated point detectors, ProReact LHD provides an uninterrupted zone detection pathway that triggers an alarm the moment a set temperature is reached, ensuring fires at detected at the source, whether that ignition begins deep within high-bay racking, inside plant rooms, or along automated conveyor systems.

Unlike conventional detectors that can be affected by airflow, condensation, or extreme temperatures, ProReact LHD is purpose-built for sub-zero environments, maintaining dependable performance even in conditions as low as -60°C.

The ProReact Programmable range adds a further layer of protection through an optional rate-of-rise alarm mode, accelerating response when a rapid temperature increase is detected, particularly valuable in cold storage, where early signs of fire can be masked. This approach supports fast, accurate detection while helping to minimise false alarms that can disrupt operations or put valuable stock at risk.

Installation Guidance for Cold Storage Applications

For effective fire detection in cold storage, Linear Heat Detection (LHD) should be installed to follow the racking layout, running both along aisles and storage areas to ensure coverage of key risk zones. Positioning the cable close to likely ignition points help improve detection speed and accuracy.

Installation must account for sub-zero conditions, including maintaining appropriate cable support and a minimum bend radius of 150mm (6 inches) to protect long-term performance. Mountings should be installed at regular intervals using accessories suited to freezing environments, while controllers and interface modules should be located outside the area to avoid exposure to condensation and extreme temperatures. 

When installed in line with these principles, ProReact LHD provides reliable early-warning fire detection across cold storage facilities.

Compliance and Insurer Recommendations for Cold Storage Fire Detection

Insurance and risk engineering guidance consistently supports the use of heat-based fire detection in cold storage. Gallagher notes that low-temperature environments require “advanced fire detection systems” and, depending on conditions, may rely on fixed-temperature or rate-of-rise detectors. AXA XL Risk Consulting also identifies linear heat detection as an approved device for preaction systems in freezer environments. FM Global DS 8-29 reinforces this approach by requiring fixed-temperature detection devices for refrigerated storage, a category that includes Linear Heat Detection (LHD).

This alignment across insurers and standards bodies highlights Linear Heat Detection (LHD) as a reliable and compliant choice for cold storage fire protection.

Conclusion

Cold storage fire detection requires technologies engineered specifically for sub-zero environments, concealed ignition risks and disruption airflow. As facilities increase in scale, effective early warning becomes critical to reducing loss, operational disruption and wider cold chain impact.

ProReact Linear Heat Detection provides a proven, insurer-aligned solution that supports long-term fire protection resilieince designed to perform reliably in demanding conditions.