NFPA Journal

Audio: Listen to this article.

On May 11, 2017, a late-night fire broke out at buffalo farms freezer and cold storage, a fruit-packing and storage warehouse located in Hammonton, New Jersey.

The facility used more than 40,000 square feet of cold storage, freezer, and repacking space, and had recently expanded before the incident. In interviews, neighbors said there had been a significant increase in activity at the facility, with as many as 30 to 40 trucks per day visiting the property. Fire departments from five neighboring counties were needed to extinguish the fire, which reportedly started from hot work—in this case, welding—activities taking place on the structure. No serious injuries occurred, but damage was assessed at more than $3.5 million, with the building ruled a total loss.

The Buffalo Farms example illustrates the activity taking place in the cold storage industry as well as the hazards that exist. Driven by emerging distribution models for perishable goods and pharmaceuticals, the cold storage industry is undergoing a period of significant growth, with millions of square feet of new storage space under construction or planned around the country. The US cold storage market is expected to reach $19.69 billion by 2025, based on an annual growth rate of nearly 4 percent, according to a report by Grand View Research.

I live in Pennsylvania’s Lehigh Valley, where more than 10 million square feet of warehousing, both cold and ambient—the term used for the storage of goods that do not require refrigeration—has been constructed in the past six years, with an additional 8 million square feet slated to break ground in the next two years. While not all of these facilities are big square boxes looming over the landscape, it’s apparent they are becoming more diverse and designed for specific needs. My wife makes a negative comment every time we drive past another warehouse under construction, but she also enjoys meal-kit delivery services that are helping drive the demand for those facilities.

Cold Hazard A 2017 fire destroyed the Buffalo Farms Freezer and Cold Storage facility in Hammonton, New Jersey, resulting in an estimated loss of $3.5 million. Safety experts warn that the scale and contents of these facilities are creating new hazards that will need to be addressed by safety processes, technological advancements, and code development. Photograph: THE PRESS OF ATLANTIC CITY

As cold storage proliferates, designers, builders, owners, authorities having jurisdiction, and other stakeholders must address the hazards presented by these facilities. The stored goods themselves often constitute a potential hazard, as do the building materials, electrical systems, refrigerants, and other elements that go into creating cold storage environments. Even in instances where fire results from external factors, such as hot work in the case of the Buffalo Farms fire, elements of cold storage environments can contribute to the severity of the fire and the dangers faced by firefighters and other responders. In my work as a product manager for Victaulic, it is essential to support the industry effort to evaluate and address these hazards. As a result of this work, our team of engineers can identify new activation devices, design configurations, and installation joining methods that address these emerging challenges related to cold storage.

Working alongside industry, NFPA is also addressing cold storage issues. The 2019 edition of NFPA 13, Standard for the Installation of Sprinkler Systems, for example, includes updates that address a range of design standards, guidance I helped shape as a member of the Technical Committee on Sprinkler System Installation Criteria. This new information in NFPA 13 means that system designers, insurers, the fire service, and other cold storage stakeholders have the best and most up-to-date information at their fingertips to help them protect these facilities.

CONSUMER DEMAND AND COLD STORAGE

As consumers continue to put an emphasis on health and convenience, it’s no surprise that a significant amount of growth in the cold storage market can be attributed to online grocery sales, especially perishable goods. Whether through meal-kit delivery services, online giants such as Amazon, or membership-based online wholesalers, it has become the norm for perishable items to ship straight to consumers. According to the Food Marketing Institute, online grocery sales are expected to rise from 3 percent of all US grocery sales in 2017 to 13 percent by 2024.

Large commercial real estate investors are taking notice. According to a recent analysis by The CBRE Group Inc., the projected growth in online grocery sales is already having a major impact on the development of new climate-controlled warehouse space, with an estimated 35 million square feet of additional space projected nationally over the next seven years. This number does not include all the other free space that is being converted to cold storage. Most of that new construction will occur in areas with substantial agricultural production, large populations, and/or access to distribution networks, according to CBRE.

One piece of the perishable goods puzzle to highlight is the increase in delivery services for meal kits, which are pre-prepared ingredients for cooking a variety of meals. My wife and I have busy work and family lives, and meal kits allow fast, healthy meals without grocery shopping. Meal-kit sales reached $2.6 billion in 2017, with projected sales of $3.1 billion in 2018, according to Packaged Facts, a Maryland-based research firm. As consumer trends change and home delivery of fresh food replaces trips to the local grocery store, it’s no wonder the distribution model of perishable goods needs to react.

Another trend affecting cold storage is the significant increase in pharmaceutical products requiring refrigerated storage. Much of that growth is attributed to temperature-controlled vaccines and biologic drugs, which are produced from living organisms or contain components of living organisms. Of the 57 new drug approvals issued by the US Food and Drug Administration in 2017, almost half required climate-controlled storage and transportation for approval. According to Pharmaceutical Commerce, a health care commerce media corporation, the segment of pharmaceutical products that require cold storage and transportation is anticipated to grow 70 percent by 2021.

Market Forces Temperature-controlled facilities used for pharmaceuticals and home-delivery grocery services will continue to drive demand for cold storage space, industry experts say. Photograph: Getty Images

Considering those kinds of projections, it’s no surprise that online distribution giant Amazon is evaluating the opportunity to enter the pharmaceutical distribution business. According to a recent CNBC article, warehouse and logistics infrastructure was outlined as a barrier to entry for Amazon, as most of the company’s current distribution network is not set up to store and deliver temperature-sensitive pharmaceutical products. But similar barriers to entry presented themselves when Amazon entered the perishable-foods distribution market, and unique solutions such as acquiring Whole Foods Markets allowed Amazon to minimize logistics headaches. The Whole Foods acquisition alone put 440 “refrigerated warehouses” within 10 miles of almost all of the 95 million Amazon Prime subscribers. Experts say it’s only a matter of time before Amazon makes the jump into pharmaceutical storage and distribution.

COLD STORAGE AND ITS CHALLENGES

With these shifts already underway, it’s vital that the storage industry reevaluates the most effective ways to protect these spaces, and that it focuses on areas and processes where problems could arise. This challenge becomes more complex as more warehouses are built for application-specific uses rather than as empty big boxes.

Envelope cold storage spaces, for example, are considered big boxes, where the entire building is insulated and conditioned to a specified temperature for the commodity they protect. This type of storage space needs to be designated and planned from the beginning, so the design and specification of fire protection systems happens early in the new-construction process. This type of application calls for dry or preaction fire sprinkler systems. This approach can feature control mode specific application sprinklers at the ceiling, or in combination with in-rack sprinkler and ceiling protection as part of the design. (Warehouse operators and designers sometimes prefer to avoid in-rack sprinklers and associated piping, however, due to the potential damage from fork truck and pallet impacts.) Higher ceilings, and therefore a larger volume of space under each sprinkler, demands a large amount of water to protect property when in-rack sprinklers are taken out of the mix.

In some cases, cold storage–specific facilities—those built for a limited commodity type—aren’t always practical due to the need for mixed storage types. In those cases, the best solution can be the installation of conditioned spaces in combination with ambient warehousing—what’s known as a “box-in-box” facility. In many instances, existing warehouse spaces are retrofitted to include box-in-box conditioned spaces, where a cooler or freezer is constructed in a larger warehouse. Box-in-box conditioned spaces can also be incorporated within new-construction ambient warehouses. This application provides flexibility for warehouse operators to transform back to open space once a tenant ends the lease. It is also seen as an attractive option for repurposing old warehouses or retail locations to meet the demand for temperature-controlled facilities. A good example of this application is Amazon’s acquisition of Whole Foods, and how the facilities will serve in-person consumers while also being retrofitted for new online grocery shoppers.

Typically, this type of dual application employs wet systems with dry pipe systems for the conditioned spaces. The naturally lower ceiling heights and proximity of reliable water supplies in this instance will drive the type of dry sprinkler used to penetrate the conditioned space. These sprinklers can be either control mode density area (CMDA) or early suppression fast- response (ESFR)–type sprinklers.

While it may seem counterintuitive that fire is even a risk in spaces designed to maintain cold temperatures, cold storage in fact presents a number of fire protection challenges, notably that most products stored in these facilities are combustible. Frozen foods, processed dairy such as butter and cheese, and food coloring are often considered combustible and are typically considered Class III commodities. In 2017 in Wausau, Wisconsin, fire destroyed a 60,000-square-foot refrigerated storage facility owned by Central Storage and Warehouse Co. The warehouse included multiple storage rooms to provide individual temperature control settings for aging specialty cheeses.

Storage and delivery materials can also be combustible. Meal kits, groceries, and pharmaceuticals are delivered in cardboard boxes or on polystyrene trays that are often stored on larger cardboard pallets in the storage space. Dried cardboard and polystyrene can be the perfect fuels to complete the fire triangle of oxygen, heat, and fuel; testing entities such as UL and FM Global condition cardboard boxes to a moisture content between 4 and 8 percent so they can test and approve sprinklers and system design under the most challenging circumstances. For comparison, the moisture content of a dry Christmas tree is around 24 percent.

Construction materials and systems also pose potential risks in cold storage spaces. High-intensity discharge (HID) lighting, common in modern warehouses, poses a serious risk—the temperature inside the light bulb can reach about 1000 degrees. An NFPA study, “Structure Fires in Warehouse Properties,” found that 18 percent of warehouse fires from 2009 to 2013 were attributed to electrical distribution and lighting equipment. The combination of this heat source and the fuel (often cardboard boxes) stored below it can create a perfect storm of warehouse hazards. Ammonia-based refrigeration equipment also presents fire concerns, and at concentration levels of 15 to 28 percent, ammonia can serve as an accelerator if a fire breaks out from a different source. Additionally, the polyurethane and polystyrene foams commonly used as insulators in cold storage facilities are highly combustible.

Fork trucks, lifters, hot work, and arson are also among the leading causes of fire in cold storage facilities.

CHALLENGES GOING FORWARD

As the cold storage market expands and evolves, stakeholders will continue to raise questions on protecting these facilities with the best options for fire protection, property protection, and strategies for moving and storing materials. Many of these questions can be answered with better education of the product options in the market, including making more design options available in installation standards such as NFPA 13.

These are just a few of the challenges that can be roadblocks to superior fire protection, which comes from designing systems to deliver large volumes of water within required delivery times. Since these applications are prone to freezing, the design must ensure that systems only release water when absolutely required—false system activations with dry and preaction systems can be very expensive mistakes. Care must be taken with the torque applied to traditional large threaded sprinklers when they are installed into an outlet—a consideration that is not unique to cold storage applications, but one that bears repeating nevertheless. Using the incorrect sprinkler wrench can potentially lead to complications like over-tightening and over-torqueing, potentially causing weak points that could result in leaks. Additionally, construction schedules need to be considered when determining the correct fire protection solutions. The time associated with sprinkler prep work, or the down time waiting for foams and glues to set and cure around pipe penetrations, may contribute to lost overall productivity, but they are essential to achieve a fully functional system.

The seal integrity of box-in-box applications is also a significant concern. When the conditioned space is penetrated by every sprinkler, isolating the potential for differential movement between the shell structure and the insulated structure is critical. Whether it’s due to refrigeration system vibrations over time, stress on the insulated structure due to service foot traffic, or a roof sagging from snow loading, fire protection systems are at risk of having the foam or glue break around penetrations, causing unwanted condensation and ice buildup.

The combination of the shifting demand and identified opportunities to improve cold storage fire protection is helping produce many of the latest technological advances. Higher ceiling-only sprinkler approvals, “smart” sprinklers, dry and preaction sprinkler systems filled with nitrogen, larger K-factor dry sprinklers with flexible connections for box-in-box, and oxygen reduction are among the new technologies the market needs to explore. Codes and standards developers will need to remain vigilant to ensure that codes keep up with the technological advancements occurring alongside this rapidly expanding industry.

DANIEL WAKE is product manager for sprinklers and valves at Victaulic. Top Photograph: Newscom