Storage Metters

The size, contents, and technological complexity of modern warehouses are making storage occupancies some of the most challenging buildings for the fire service to protect. A comprehensive new study by the Fire Protection Research Foundation identifies the pain points and charts a promising way forward.

Scott Sutherland - Executive Editor, NFPA Journal

In october, the online retailer Amazon held a ribbon-cutting ceremony for its new warehouse in Ontario, California. The observance included performances by the dance team and marching band from a nearby middle school, as well as appearances by a host of local dignitaries. “This is not your father’s or grandfather’s warehouse,” Ontario Mayor Paul Leon told the gathering. “This is the warehouse of today and the future and this is the warehouse that gives you that right-now delivery.”

The mayor’s assessment was spot-on in a number of ways. The new facility, which began operating in July, models an array of current trends in global storage occupancies, starting with its sheer size. The Amazon facility encompasses about 4.5 million square feet—nearly 70 football fields—spread over six stories, making it Amazon’s largest warehouse and one of the largest storage occupancies in the country. The warehouse is designed to hold an immense variety of goods—up to 50 million items, an inventory that can be constantly monitored and fine-tuned based on consumer demand. According to published reports, the Ontario facility processes as many as a million shipments each day. To help the facility’s workforce of about 2,000 expedite those orders—the “right-now delivery” hailed by Mayor Leon—Amazon incorporated more than 7,000 robots into the design of the warehouse, which is also known as the Robotics Sortable Fulfillment Center. 

All of these features can keep local fire department officials up at night. Across North America, larger and more complex storage facilities spanning a range of industries—retail, chemical, food and beverage, and others—are creating new challenges for the fire service. The overall size of these buildings, as well as a heavier reliance on automation inside these facilities, can result in spaces that are harder for responders to reach. However, most of the suppression systems in these occupancies are still designed to only control a fire rather than extinguish it—that task is left to firefighters, who may or may not have the training and resources necessary to safely accomplish it. Like the new Amazon facility, many storage occupancies, especially those in the retail sector, are characterized by a constantly shifting inventory that can make it difficult for fire departments to conduct pre-incident planning. More concerning are the storage facilities that are home to a growing array of potentially hazardous goods, including the galaxy of consumer products powered by lithium-ion batteries, which can react violently and unpredictably when exposed to fire. For these reasons and others, the fire service increasingly regards storage occupancies as some of the most challenging structures to protect. 

“Across North America, larger and more complex storage facilities spanning a range of indutries - retail, chemical, food and beverage, and others - are creating new challenges for the fire service”

To address these concerns, the Fire Protection Research Foundation (FPRF) commissioned a comprehensive new study to identify the challenges of greatest concern to the fire service when planning and executing responses to fires in storage occupancies. The report, “Identifying Challenges to Fire Service Response in Storage Facilities,” released in December, includes the results of roundtable discussions, literature reviews, and knowledge gap identification to devise a research plan to assist the fire service in fighting fires in storage facilities. 

Of particular interest was the virtual fire service focus group, held last April. The group included 19 representatives from the U.S. fire service, ranging from large urban departments to small rural departments. The goal of the meeting was to gain insight into the challenges that the fire service encounters in storage facilities. The four-hour discussion, hosted by the FPRF, was led and facilitated by members of the project team with predetermined questions that were developed based on the FPRF proposal and the project team’s work in researching large-loss fires. The questions included: 

• What challenges is the fire service seeing when preparing for fire incidents in storage facilities? 

• How are fire departments preparing for incidents in storage facilities in their jurisdictions?

• What additional resources do fire departments need to respond to fires in storage facilities? 

• What support does the fire service need from building owners, insurers, facility managers, and others? 

• Who else should be part of the discussions on this topic? 

The discussion yielded a number of common denominators among fire service participants; those responses, as well as context for the discussion, are included in an extended excerpt from the report that appears below. A summary of the meeting, along with responses and the results of a follow-up poll, are included in the final report. 

FROM THE REPORT 

Incident pre-planning challenges 

When it came to pre-planning for large storage warehouse facilities, the fire departments in the focus group discussed visits to these facilities and interfacing with facility staff as well as familiarization with locations of fire department connections, hydrants, etc., and ensuring that access for fire apparatus was available. The challenges with preparing for an incident at these types of facilities included high-dollar value contents and automated storage and retrieval systems (ASRS), some of which may be high voltage. Only one department representative mentioned using a process similar to NFPA 1620, Standard for Pre-Incident Planning, or NFPA 1660, Standard for Emergency, Continuity, and Crisis Management: Preparedness, Response, and Recovery. The difficulty in buildings that are “spec” built without tenants or storage arrangements was brought up during the discussion. Information may be gathered during a site visit by a fire suppression company but may not be effectively communicated to other companies or neighboring departments that will respond to the building. 

Due to the size and construction of these buildings, ensuring proper radio coverage and use of in-building air replenishment systems (ARS) were also discussion points when addressing preplanning. 

With respect to new construction, there was a consensus that getting involved early on was important, but the level of involvement was different from department to department. There were some jurisdictions where the elected officials luring businesses like these to the area did not involve the fire department in the discussions before construction. One jurisdiction that had suffered a total loss of a large warehouse found that their elected officials were now asking more questions in terms of fire safety as it relates to these types of buildings. In some areas, the developers were often required to pay for infrastructure upgrades, but the upgrades and resources didn’t seem to translate to firefighting. When improvements were made to firefighting, it was mostly equipment versus personnel to fight a fire. In the jurisdictions where suppression personnel were involved early on during construction and frequently visited the site, they were more familiar with the building once it was occupied. 

As far as interfacing with the insurance carrier for a new building, the discussion ranged from departments that never talk to the insurance company to those that work collaboratively with it to ensure safety in the building. This may be an area of gaps, where the fire department is assuming that the insurance carrier is looking at the building and ensuring that it is fire safe, and the insurance carrier is assuming that the fire department is frequently inspecting the building for the same reason. There was also apprehension from some fire service participants about reaching out to the insurance carrier and creating a rift with the building owner.

The discussion of new structures included asking the participants if they were calculating manual fire flow for these buildings and what methods were being used. More than one participant mentioned using Appendix B of the International Fire Code as the basis for the approved method of manual fire flow calculation. ISO was also mentioned as a method used to determine required fire flow. Those that had responded to these types of fires provided insight into how much water was used in their incidents. One indicated that the sprinklers and building fire pumps were flowing 4,000 gpm and their manual hose lines and appliances were flowing 18,000 gpm at the peak of the fire for a total of 4 million gallons of water used for fire suppression. Another participant provided information that in a fire his department had responded to, the sprinklers at the peak of the fire for a total of 4 million gallons of water used for fire suppression. Another participant provided information that in a fire his department had responded to, the sprinklers were flowing 2,000 gpm and the manual firefighting appliances were flowing 8,000–10,000 gpm for a total of 125,000 gallons of water used for fire suppression. Concerns were voiced about not enough water being available. 

Participants were asked about any unique hazards that exist in their jurisdictions and if they are notified either during new construction or as a change in an existing warehouse. Some of the unique hazards that the fire service representatives identified were hazardous materials, automated storage and retrieval systems, lithium-ion battery storage, combustible dusts, and simply changing commodities. The safety culture of the facility was brought up as a major factor in whether these hazards have been addressed correctly or not. A participant brought up that during a fire at a storage facility containing boxes of paper on racks, they had a major collapse of the rack structure within approximately 15 minutes of fire units arriving on scene. This was brought up to indicate that, while not a hazardous material or a new technology, something as simple as a product that absorbs water discharged from sprinklers can cause a hazard to manual firefighting activities. The additional weight of the water absorbed by cardboard cartons filled with records being stored caused the collapse of the rack structures, since the racks were not designed for the added load created by the water. With some of the newer hazards, the fire service representatives brought up that the scale of things being built or stored is beyond what is addressed in the codes or that the codes haven’t caught up to the materials or new technology that they are seeing in the field. 

Participants were asked about changes in existing warehouses and their involvement. There are times when this is captured, such as when a permit is required for tenant improvements, changes in processes, or addition of hazardous materials storage or use. Other than those circumstances, the fire service is relying on the owner to bring changes in commodities, storage arrangement, or additions of new technology to their attention unless it is noticed during a fire prevention inspection. In terms of prioritization of these facilities for fire prevention inspections, it was mentioned that only facilities with hazardous material storage would be a high priority and that resources weren’t readily available to annually inspect all of the storage buildings in the jurisdiction. It was also noted that according to NFPA 1730, Standard on Organization and Deployment of Fire Prevention  Inspection and Code Enforcement, Plan Review, Investigation, and Public Education Operations, these buildings would be low-risk occupancies, only requiring an inspection every three years. Therefore, management of change is required by the owners or operators along with effective communication to the fire service. 

When it came to discussing system impairments and fire department notification, there was not a high degree of confidence among participants that they were being notified every time a system was impaired.  One participant indicated that only when a “whistleblower” alerts the fire department of an impairment do they receive notifications. Another participant stated that they thought impairment do they receive notifications. Another participant stated that they thought they were getting a high percentage of notifications of system impairments but “we don’t know what we don’t know.” Most participants indicated that a fire watch was required in these facilities for longer impairments, which some allowed to be facility personnel and others required fire service personnel for conducting the fire watch. One fire service representative said temporary water supplies or portable pumps weren't required when those components were out of service, but perhaps they should be. Another participant stated that they required drafting connections on tanks to allow fire apparatus to utilize the water supply if the stationary pump didn’t start or was otherwise out of service.

Fire department response issues 

In terms of responding to these buildings, participants indicated that the response would be different depending upon the notification they received (i.e., fire detection device versus  waterflow versus employee calling to report a fire). Some respondents indicated that due to the large amount of work in manual firefighting in these buildings, they have a modified response. Others stated that they were considering the same. One participant relayed a story regarding a fire in a storage building in their jurisdiction where the arriving company was alerted to a working fire by the exiting employees, yet no one called 911 to report he fire, assuming the fire alarm had started fire department response. 

When attacking a fire in a large storage building, there was concern from the fire service representatives about getting too far into these buildings. One department has a policy of not going deeper into a building than 150 feet, but is currently evaluating what would need to be in place in order to allow for greater distances. In some of the multistory storage buildings with stair shafts, the fire service participants indicated that they would utilize the standpipes that are located within them. There was concern expressed for carrying hose that is not charged with water deep into a building to connect to a standpipe hose connection on a rack or building column. It was indicated that those standpipes would be useful for “mop up.” The participants were asked what additional was concern expressed for carrying hose that is not charged with water deep into a building to connect to a standpipe hose connection on a rack or building column. It was indicated that those standpipes would be useful for “mop up.” The participants were asked what additional resources the fire service might need to fight a large storage building fire. Answers varied but included heavy machinery, which may already be available from wildfire agencies, truck-mounted fans or airboats for ventilation, and technology such as drones and robots. 

The focus group was asked about how employees in a large storage building are accounted for. It was acknowledged that this is probably the toughest job that needs to happen on the scene of a fire in this type of building. In some instances, the employees were responsible for accountability in their own small groups. Since the number of employees in these large buildings can be in the thousands, some jurisdictions will make them meet the requirements for a factory in terms of conducting drills when there are large numbers of employees present. In facilities with card in/card out systems, management should have a clear picture of who is present in the building at any given time. One jurisdiction commented that during a fire they had in this type of facility, it was determined that employees were abusing the system. One person was swiping in multiple cards of employees that were not physically present, which led to problems accounting for all occupants. 

It was noted that only a few facilities had their own on-site fire brigades, and only very few had on-site fire apparatus. In all cases, the fire brigade would provide first aid firefighting but then withdraw upon the arrival of the responding fire department.  One participant stated that it would sometimes create a delay in notification of the responding fire department as fire brigades attempted to handle problems internally before calling for assistance.

In a discussion of training within these buildings or handling a fire in some of the newer systems such as ASRS or oxygen reduction systems (ORS), there was little to no input or experience from the fire service with this. Most if not all participants indicated that thermal imaging was available to companies to assist in locating the fire and occupants. The fire service representatives did indicate that ventilation systems in the building were very important, as most fire departments would not put fire crews on the roof to manually ventilate the structure.  The timing and decision of when to ventilate was also an important factor for the fire service, specifically in terms of how it relates to successful operation of the sprinkler system. 

It was also mentioned that mutual aid companies that respond in an actual emergency need to be involved in training and become familiar with the building and its installed systems. The participants discussed at what point the determination would be made to enter or to not  enter the structure for manual firefighting efforts; the most common answers were signs of collapse of building or rack systems,  inadequate water supply, inadequate resources on scene, or involvement of hazardous materials. 

The fire's out. Now what? 

The discussion then moved to post-fire or recovery. The first question was when participants considered the fire extinguished; answers discussed the completion of overhaul activities and removal of all burned materials. There was also conversation about when the fire pump or water-based systems should be turned off in order to assist in overhaul without leading to a hidden fire growing in size. 

There was not much input from the participants in terms of how to retrieve burned materials from inside a large ASRS storage system or on a large rack unit and remove then to the exterior of the building. Once a building is structurally compromised this becomes a moot point. Often due to the high-dollar-value loss and desire for the insurance carrier to find a cause, they will not want large amounts of material removed. The same is true if the fire is considered a crime scene. With the size and magnitude of structures and contents, this may need to be done with an excavator and other heavy equipment. 

Fire service representatives also highlighted the importance of having accurate, up-to-date information about the facility and establishing a relationship with facility management for after-hours contacts and as changes occur. Being able to quickly determine what products are stored where and in what quantities is also valuable to the fire service when responding to or planning a response to these types of buildings. The critical nature of knowing if all occupants are accounted for early on during an incident is important, as it changes the complexity of the incident for the responding fire department.

POSTSCRIPT 'Assume nothing': The next steps for research 

In their preface to the report’s 12 recommendations, part of the scope of proposed research, the authors offer a qualification for their findings. “Part of the feedback that the research team received was a caution against focusing too much on emerging issues and/or ‘high challenge’ scenarios,” they write. “Such scenarios, while important, represent a small portion of the storage buildings currently in operation. Since  the research goal of this project is to identify the challenges that the fire service faces in fighting fires in storage facilities, the project must consider as many types of storage facilities as possible. Neither this research team nor any follow-on researchers should assume that there is nothing left to be learned about ‘typical’ storage facilities.”

That inclusive, “assume-nothing” approach is intended to help the fire service address any issue associated with storage occupancy fires. “When implementing the research plan … deliberate care should be taken to ensure that the research is as comprehensive as possible and will benefit the broad range of facilities, jurisdictions, and fire departments,” the authors conclude. “In particular, the topics of standardization, fire service/building owner interaction, and use of water supplies affect virtually all storage occupancies in some way and therefore should have a broad scope to ensure that any conclusions and/ or recommendations will be widely applicable. Nevertheless, some research topics will necessarily be narrower in their scope and applicability.” 

Click here to read the original version published in the SPRING 2025 issue of NFPA JOURNAL.

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This article is reprinted with permission from NFPA Journal, © 2025 NFPA..