Warehouse Fire Protection, A Strategic Approach

Warehouse Fire Protection, A Strategic Approach

Fire protection is a fundamental aspect of warehouse safety. The increasing complexity of modern storage systems requires a proactive approach to mitigating fire risks. When designing a new warehouse, fire protection should be as critical as site selection, utility planning, building layout, and inventory management systems.

Warehouse operators must assess fire suppression needs early in the site selection process. Storage configurations, commodity classifications, and retrieval methods all influence fire load and suppression requirements. Addressing these factors from the outset ensures compliance with fire codes and minimizes fire hazards.

This blog, Warehouse Fire Protection, A Strategic Approach explores essential fire protection strategies that warehouse designers, owners, and operators should always consider.

Understanding Fire Protection in Warehouses

The commodity classification of stored materials is a key factor in fire protection planning. Each material's flammability, heat release rate, and fire resistance determine the required suppression system. Understanding these classifications ensures compliance with fire codes and prevents catastrophic losses.

Another major consideration is “allowable building areas,” and where, when or if maximum foreseeable loss (MFL) fire walls are considered, vs. “standard” fire-rated wall construction. “MFL” walls, outlined in FM Global Data Sheet 1-42, generally provide four-hour fire resistance and remain structurally stable even if adjacent ceiling(s) collapse. They act as a safeguard against large-scale fire spread, and consider worst-case fire scenarios.

10 Key Fire Protection Considerations for Warehouse Fire Protection, A Strategic Approach

1. Storage Density and Fire Suppression Needs

High-density storage requires a detailed evaluation of commodities and their retrieval methods. Whether using automated storage and retrieval systems (AS/RS) in multi-row rack assemblies, or traditional palletized and/or double-row rack storage, the storage method, height and density significantly influences fire suppression or fire control requirements.

2. Storage Height and Rack Configuration

The height and arrangement of racks impact fire spread and sprinkler effectiveness. Tall storage structures require specialized sprinkler designs and layouts to ensure proper fire coverage. Bulk storage methods and densities also affect how quickly fire can spread between pallet loads or piles.

3. High-Density Storage and In-Rack Sprinklers

Warehouses with high-density storage often require in-rack sprinklers. These sprinklers provide additional protection in areas where standard ceiling-mounted systems may not offer full coverage. Care must be taken in the design layout of these sprinklers to ensure their effectiveness, that they meet code, and that there are no obstructions to their operation.

4. Water Supply and Hydraulic Complexity

In-rack sprinklers demand higher waterflow rates, at specified “end-head pressures,” increasing system complexity. Adequate water supply planning, hydraulic calculations and equipment selection by a seasoned fire protection engineer will help ensure that the automatic sprinkler systems will operate as designed in an emergency.

5. Aisle Spacing and Fire Spread

Narrow aisle spacing and high pallet load desnity allows radiant heat to transfer between storage rows or pallet loads, increasing risk of fire spread. Wider aisles may slow fire spread and improve accessibility for fire suppression efforts.

6. Compliance with Fire Codes and Standards

Adhering to fire protection codes is essential for warehouse safety. Consulting fire protection engineers ensures compliance with NFPA (National Fire Protection Association) Codes and Standards, International Fire and Building Codes, and FM Global Data Sheets. Professionals familiar with using these standards can guide in-rack barrier placements, sprinkler piping layouts, sizing of sprinkler risers and underground water mains, fire pump sizing, and water supply reliability.

7. Risks from Battery-Powered Equipment

Many automated warehouses use battery-powered retrieval systems. These systems introduce unique risks, sespecially where Lithium-ion batteries are used, which can result in thermal runaway events or physically-damaged equipment. Proper planning for energy storage systems and/or battery-powered equipment is essential, especially as standards continue to evolve.

8. Obstructions to Fire Suppression Systems

Sprinklers must remain unobstructed to function properly. Building steel, lighting fixtures, and ventilation systems can block sprinkler system coverage and effectiveness. Early coordination between construction trades helps prevent costly installation errors. Overlays of construction drawings that include the ceiling and in-rack storage sprinkler systems layouts are essential.

9. Hazardous Materials and Fire Risk

Warehouses storing flammable liquids, oxidizers, aerosols, and Group A plastics typically require specialized fire suppression or control systems. Fire protection designs and storage layouts should identify chemical incompatibility, and fire containment strategies.

10. Segregation of High-Risk Commodities

Certain products, such as pool chemicals and flammable solvents, pose heightened fire risks. Storing these items separately reduces fire hazards and ensures compliance with fire safety standards or guidance. Plastic intermediate bulk containers (IBCs) storing “ignitable liquids” (liquids capable of burning) require additional safety precautions, as they pose a more significant hazard than ignitable liquids in the more traditional steel “totes,” also known as “IBCs.” NFPA 30, Flammable and Combustible Liquids Code, also has prohibitions on the use of plastic IBCs (as well as restrictions involving certain other plastic containers) for flammable liquids.

"Warehouse Fire Protection, A Strategic Approach" Means Avoiding Common Fire Protection Mistakes!

Proper fire protection requires more than just following codes, standards and guidelines. It requires learning from mistakes. Here are some common mistakes to watch for:

• Inadequate water flow and pressure that can render the fire suppression systems ineffective.
• Undersized underground water supply piping -or- inadequate local water supplies that may not deliver the required sprinkler system demands.
• Poor quality piping, fittings, and/or couplings can lead to system failures.
• Improperly-sized fire pumps can reduce fire suppression effectiveness, and are expensive to change out later.
• Failure to test fire pumps according to NFPA 20 standards can compromise system reliability.
• Lack of seismic risk considerations can result in significant structural damage to sprinkler piping or storage racks, leading to large-scale water damage, inventory damage, and potentially fire during earthquakes. Seismic gas valves and excess flow valves should be evaluated where the warehouse is located in an affected seismic zone.
• Ignoring external risks, such as flood, wind, wildfire exposure, or an unreliable electric grid can increase fire or weather-related loss vulnerability.

Warehouse owners and operators should proactively identify and resolve these issues prior to construction (or lease-signing) to ensure a robust fire protection system and viable operation for the years ahead.

"Warehouse Fire Protection, A Strategic Approach" Means Integrating Fire Safety into Warehouse Design!

Fire protection is a forethought - not an afterthought in warehouse design and planning. Integrating fire and life-safety with 5S principles, operational excellence, and floor delineation strategies for lift trucks, pedestrians, and commodities creates a safer work environment. 

Mighty Line^® floor striping and marking products can enhance fire and life-safety by clearly designating lift truck operating lanes and safe travel routes for employees and visitors, while delineating hazardous zones necessary for machinery, equipment, or electrical panels and fire protection equipment such as portable fire extinguishers or hoselines. Mighty Line’s floor tapes are known as the most durable and best in the industry, with custom beveled edges and a 3 year limited warranty. Be sure to also consult the new Mighty Line OSHA/ANSI/ISO Safety Color Guide for color advice and ideas on your next project!

Stay safe!