Top 6 Warehouse Fire Protection Features to Consider During Design and Construction

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Austin Grant, P.E.

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May 26, 2023

When designing a new warehouse, it’s essential to plan for fire protection features, as this helps protect people and property in the event of a fire. Here are six features to consider for your warehouse design.

Unfortunately, warehouse fires are all too common. In the United States, it’s estimated that fire departments respond to an average of 1,450 structure fires in warehouse properties per year, excluding refrigerated or cold storage facilities.

One way to combat warehouse fires is to implement warehouse fire protection features from the very beginning. Everyone involved in the design of the warehouse – architects, engineers, developers and owners – should work together to determine the necessary safety features. Otherwise, you could have a construction disruption or delay in the permit approval process, leading to increased costs that weren’t part of the original budget.

So, what kind of warehouse fire protection features should you consider for your project? Let’s explore them now.

Top 6 Warehouse Fire Protection Features

1. Proper Analysis and Commodity Classifications

Commodity classification is the categorization of various goods and materials based on their potential fire hazards and risks in the warehouse. The commodity classification will dictate the necessary features of warehouse fire protection and path to code compliance, which is why it should be the very first consideration.

The National Fire Protection Association (NFPA) offers guidance on commodity classifications. For warehouses, these classifications typically include:

  • Class I: Noncombustible products that are placed on wood pallets. They are pretty low risk because of the way they are stored in pallets, cartons or shrink-wrapped.
  • Class II: Noncombustible products that are stored in a heavier type of combustible package, like a wood crate or solid wood box.
  • Class III: Ordinary combustibles like wood, paper, and natural fibers.
  • Class IV: Some level of plastics that are put into containers or materials from other commodity classes that have up to 15% of plastic materials within them.
  • Group A plastics: Different types of plastics, including PET plastic bottles and PPC piping for fittings.
  • Rubber tires
  • Rolled paper

In addition, there are high-hazard commodities to consider, such as flammable and combustible liquids, solids and gases, as well as corrosives, oxidizers, aerosols, and explosives. These materials require special consideration by establishing maximum allowable quantities(MAQs) in separated control areas. The code compliance approach for high-hazard occupancies is required to be documented through a Hazardous Materials Inventory Statement (HMIS) and Hazardous Materials Management Plan (HMMP).

2. Construction

The type of construction material used for your warehouse plays an important role in keeping your property safe. The right materials can enhance the overall safety and protection of your warehouse, mitigate fire risks, comply with regulations, and potentially benefit from cost savings and improved insurance terms.

Most modern warehouses are constructed of noncombustible materials. However, the construction types are further classified based on the level of additional warehouse fire protection provided:

  • Type 1A: Noncombustible materials that provide the highest level of fire resistance.
  • Type 2B: Noncombustible materials with no additional fire-resistant treatments.

Consulting with fire safety professionals can help you make informed decisions about the best construction materials for your specific warehouse needs. You can even explore alternative approaches to code compliance that result in reduced initial construction costs and ongoing maintenance costs.  

3. Fire Sprinkler Systems

NFPA 13 is the standard for the installation of sprinkler systems, and it offers different design approaches based on your warehouse storage goals.

The most common sprinkler system in warehouses is the Early Suppression, Fast Response (ESFR) system. It uses large orifice sprinklers that activate quickly to control the fire as early as possible. ESFR systems are typically ceiling-level only, so they may be more demanding on your water supply.

In-rack sprinklers are placed within the storage racks. While they are less demanding on your water supply, they pose the risk of being hit by a pallet or forklift. They also offer less flexibility for storage arrangements.

It’s important to note that NFPA 13 is enforced by the local Authority Having Jurisdiction (AHJ) – your fire marshal or building code official. Property risk insurers, such as Factory Mutual Global (FMG), may have their own additional requirements on how they want to protect their warehouses, so it’s important to work with both parties to come up with a fire sprinkler system that meets everyone’s needs.

4. Proper Aisle Widths and Egress Paths

Maintaining proper aisle widths contributes to effective fire safety measures. Aisle widths consider how far apart storage racks are from each other. Wider aisles provide a couple of distinct warehouse fire protection design advantages:

  • Greater egress path capacity for occupants. 
  • Greater separation between storage arrays to prevent fire spread.

Keep in mind that the wider the aisle widths, the less space you have for storage. So, it’s a balancing act between storing as much as you can (density) within your aisles and maintaining proper fire protection, as well as the ability to efficiently access those products (selectivity).

Egress paths refer to the designated routes or pathways that occupants should follow to safely evacuate the warehouse in the event of an emergency. Since the prescriptive building code has maximum egress path distances and travel requirements, larger warehouses can run into travel distance issues. Performance-based design can help prove that the excess travel distance meets the intent of the code despite having a travel distance that surpasses prescriptive requirements. That allows you to keep your original design without sacrificing safety.

5. Fire Extinguisher Classifications and Placement

NFPA 10 is the standard for portable fire extinguishers, which provides requirements that ensure fire extinguishers are properly selected, located, inspected, tested, and maintained to effectively combat small fires and protect life and property. 

Fire extinguishers are divided into separate classifications based on the types of fires they control:

  • Class A: Ordinary combustibles
  • Class B: Flammable liquids
  • Class C: Live electrical equipment
  • Class D: Combustible metals
  • Class K: Commercial cooking equipment

There are also limits on how far apart you can place fire extinguishers based on the listed capacity of the fire extinguisher.Sometimes satisfying the prescriptive code requirements for fire extinguisher spacing can be challenging, especially for larger warehouses with long aisles where providing fire extinguishers mid-aisle would unreasonably limit the use of the space and create an unintended hazardous condition whenever forklifts and other vehicles pass each other.

Work with a warehouse fire protection engineer to determine the correct fire extinguisher classifications, placement and explore alternative design approaches for your warehouse.

6. Smoke and Heat Venting

Smoke and heat vents in a warehouse are designed to facilitate the safe release of smoke, heat, and gases generated during a fire event. They are installed in the roof or upper portions of a building to provide ventilation and aid in the post-fire smoke purge strategy.

The International Building Code (IBC) 910.3 says, “Smoke and heat vents shall be located 20 feet or more from adjacent lot lines and fire walls and 10 feet or more from fire barriers.” But from a warehouse fire protection design standpoint, smoke and heat vents can be eliminated if you have an ESFR sprinkler system. That’s beneficial because smoke and heat vents can be a big cost and maintenance issue, especially when your warehouse is on the larger side.

But what if you can’t use an ESFR sprinkler system? Like where there is insufficient water supply to support ESFR coverage or in the case of cold storage where dry-pipe systems are not permitted. In that scenario, a performance-based design approach can help prove that your warehouse doesn’t need smoke and heat vents. For example, one cold storage warehouse that contained ClassIII commodities wasn’t able to leverage ESFR protection. Per the IBC, smoke and heat venting would be necessary. Through computational fire modeling, an alternative method of post-fire smoke removal was found that did not require smoke vents on the roof. That saved the warehouse owner a lot of time and money.

Conclusion

Designing a new warehouse requires proper planning because you want to ensure your fire protection features will be code compliant before you begin construction. Remember these six warehouse fire protection features for your next design to keep your project on time and within budget while keeping your people and property safe.

Performance Based Fire Protection Engineering delivers flexible, innovative fire protection solutions for warehouses. Contact us to learn more.