Reinventing fire detection in fresh fruit and vegetable cold storage

By Khaleel Rehman

In the past year, online grocery and e-commerce shopping exceeded previous highs and it is estimated that online grocery shopping will surpass $100 billion in 2021 (Chain Store Age, February 2021).

The demand for increased refrigerated warehousing for fresh fruits and vegetables has been growing for several years, resulting in the development of new and expanded cold storage warehousing technology and structural improvements. The need for efficient, state-of-the-art cold storage development is driving warehouse refrigeration technology and logistics optimization. 

Some trends driving change in the industry include:

• Designing taller, rather than wider, warehouses which creates greater refrigeration efficiency;
• Expanding dedicated temporary storage areas with humidity flexibility to support a broad range of storage options that meet new product diversification demands; and
• Increasing adoption of micro-fulfillment centers to meet same-day delivery expectations. For cold storage, this often means an investment in automated workforce technology.

While the threat of a fire may seem minimal in cold temperatures, serious risk factors exist in food industry cold storage facilities.

Most stored goods and delivery materials (boxes, pallets, packaging) are combustible. The environment is dry with low humidity and contains multiple ignition sources. Additionally, the building’s insulated walls and ceiling can retain a fire’s heat, potentially furthering its spread, and high airflow can disperse smoke throughout the refrigerated space.

The cost of a fire goes far beyond the loss of the building structure and materials. The perishable nature of the goods, whether fresh fruits or vegetables, commonly stored in coolers, makes it essential to avoid any rise in temperature. Heat from a fire or a temperature rise due to refrigeration system downtime following a fire can result in significant stock spoilage and revenue loss. Even a spark or smoke from an emerging fire can lead to costly losses if not detected and managed early. Food products exposed to even low levels of smoke over time can be contaminated, and therefore, unusable. 

Losses caused by downtime, operation interruption, business reputation and goodwill can be significant, and could even put significant portions of the country’s refrigerated food supply chain at risk. 

Fortunately, protecting life and inventory is much easier for even the largest fresh fruit and vegetable cold storage facilities as aspirating smoke detection (ASD) technology becomes more widely adopted. Far from new, the core ASD technology has been used for decades in critical applications like data centers where early smoke detection is critical. The combination of programmable alarm threshold levels and the advantage of extracting the air sample out of harsh environment make ASD an ideal solution for these facilities.

Aspirating smoke detectors can improve a warehouse by detecting smoke at the earliest possible stage via numerous sampling points, while reducing false alarms and maintenance.

Cold Storage Smoke Detection Challenges

Fire risks are present in refrigerated storage facilities despite their low temperature. The leading causes of fire in cold storage facilities include problems with electrical distribution, lighting equipment, transport equipment faults (conveyors), maintenance operations (hot work) and arson.

Refrigerated storage facilities can present challenges in fire detection. The environmental conditions of operating temperatures, low humidity, high airflow conditions resulting in significant dilution of smoke, and the volume of high storage racking can affect airflow and impede the detection of a fire event.

Optimizing Cold Storage Smoke Detection

ASD technology is an effective, early detection option that does not require physical maintenance to access fresh fruit and vegetable cold storage facility ceiling areas above high bay racks.

Aspirating smoke detectors are well suited for food industry cold storage applications. These systems draw air samples in a continuous process through holes in long runs of durable industrial pipe mounted along the walls and ceiling.

Cold storage requires superior smoke and fire detection systems with a performance-based design approach designed to reliably operate in adverse conditions. The most advanced ASD systems can detect smoke at the very earliest stages.

Recently, an East Coast food retailer successfully deployed an advanced ASD system in an approximately 100’x100’x50’ cold storage application involving perishable vegetables. The facility is located on a site with naturally occurring methane gas and ammonia emissions, creating a need for additional protection. The system was installed with a modular gas detection component, which can detect a variety of odorless gasses that pose significant safety and liability hazards, such as ammonia, chlorine, chloride, carbon dioxide and carbon monoxide. 
 
Protecting the Bottom Line

Managers of refrigerated fruit and vegetable storage facilities who take advantage of the capabilities of ASD systems will further protect lives and inventory in these challenging environments. This level of protection may even help prevent serious supply chain disruption.

Khaleel Rehman, Khaleel Rehman is director of business development of the Americas for Honeywell Inc.