NFPA 13 Guidelines for Placing HVLS Ceiling Fans in Sprinkler Protected Buildings

NFPA and HVLS fans

The NFPA National Fire Protection Agency (NFPAis a government agency whose goal is to protect individuals and organizations from fire-related harm worldwide. They provide specific guidelines for installing and sizing HVLS fans in structures with sprinkler systems. These provisions are stipulated in the NFPA Document. This may sound very technical, especially if you don't know what HVLS are.

The National Fire Protection Agency (NFPA) is a government agency.  They provide specific guidelines for installing and sizing HVLS fans in structures with sprinkler systems. These provisions are stipulated in the NFPA Document. This may sound very technical.

Two studies looked into how HVLS fans and sprinklers work together during a fire.
These studies, conducted in 2009 and 2011, found that HVLS fans do not pose a threat to sprinkler systems.
- The 2009 study conducted by Schirmer Engineering, found that HVLS fans do not hinder the operation of a sprinkler system.
- This was seemingly  true regardless of fan placement.
- However, the only condition set was that the fans must be installed in accordance with NFPA guidelines.

.. The maximum fan diameter shall be 24 ft (7.3 m).
.. The HVLS fan shall be centered approximately between four adjacent sprinklers.
.. The vertical clearance from the HVLS fan to sprinkler deflector shall be a minimum of 3 ft.
.. All HVLS fans shall be interlocked to shut down immediately upon receiving a waterflow signal from the alarm system in accordance with the requirements of
NFPA 72


.. Provide a means of automatic shutdown for all HVLS fans.
.. Design the automaticshutdown so that power to the fan is interrupted within 90 seconds afterthe first sprinkler operates.
.. FM Approved smoke detection devices, heat detection devices, and water flow alarm devices are acceptable means to achieve automatic shutdown of fans.
.. When detectors are used, install and space them uniformly above the fan blade area.
.. Follow the recommendations in DS548,Automatic Fire Detection, and the manufacturers spacing requirements.
  
.. Arrange the installation of HVLS fan so that the fan support structure and the fandrive assembly do not obstruct the discharge pattern of the sprinklers.
Refer to DS 2-0 for general guidelines. 

What are High Speed Low Volume (HVLS) Ceiling Fans?

High Volume Low Speed fans, also known as HVLS fans was born from the idea for a huge fan with optimum airflow. From the name itself, this equipment produces high air volume while rotating at a low speed. Hence, it provides comfort without being annoying and distracting.

Since then, HVLS fans have evolved into a crucial element in planning huge buildings. They are essential to efficient air circulation in large industrial, commercial, and agricultural buildings. These fans are a need, not a luxury, especially regarding human and animal comfort.

How to choose HVLS fans when you have a sprinkler system

Most commercial and industrial buildings use alarm systems, including automatic fire sprinklers, for safety. However, it's worth noting that the presence of sprinklers can make it challenging to choose and install ceiling fans for optimal cooling. It's helpful to make sure you do thorough research and keep the local and national regulations in mind. Among the considerations are proper sprinkler spacing and the allowable maximum size of fan blades.

If these regulations sound foreign to you, don't worry, we're here to help. We will break down all the essential information you need.

Guidelines set by NFPA

According to NFPA 13, newly constructed commercial buildings that are 5,000 square feet or larger need to have a fire sprinkler system installed. In addition, if you're planning a renovation that adds square footage to an existing commercial building and the total footprint reaches 12,000 square feet or more, it's essential to remember that a fire sprinkler system installation is required.

You can read more about this regulation in this open-access document from NFPA 13.0

Proper Ways of installing HVLS Ceiling Fans

Installing HVLS fans in buildings is a great idea! They provide excellent air circulation and can make the environment more comfortable for everyone.

However, when installing HVLS fans in buildings that have sprinklers, make sure to follow these guidelines. These guidelines apply to buildings with Early Suppression, Fast Response (ESFR) sprinklers.

  • The fan diameter should not exceed 7.3 m (24 ft).
  • Place the HVLS fan in the center of the four sprinklers.
  • For safety reasons, ensure a 0.9 m (3 ft)—vertical clearance between the HVLS fan and the sprinkler deflector.
  • All HVLS fans must be connected to the alarm system. This way, the fans will shut down immediately if there's a water-flow signal. This is in line with the guidelines set by NFPA 72.

Why you need to consider NFPA 13 Guidelines

Following NFPA 13 rules makes sure that the plan and design of your building are safe and legal. Here are other reasons why you need to consider the NFPA Guidelines.

Different building structures have varying HVLS fan needs

A fan width of more than 24 ft wide in a building with a suppressive sprinkler system is in violation of NFPA 13 requirements. From Kevin Hoover's experience, this is because they never tested a 30ft fan with sprinklers. Nobody wants any liability so it won't happen until its tested.  Even though the airflow patterns are similar if not the same.

The placement of the spray heads in relation to the fan is important. It's best to put the HVLS fan in the middle of four spray heads. Depending on how you want to do it, you can either install the fans first and then set up the sprinkler system, or you can put the sprinklers first and then move the fans to fit.

Keep in mind that there must be a minimum of 3 feet of vertical clearance from the fan to the sprinkler head. This typically is not a problem as most HVLS fans require a clearance of at least three feet, depending on the size and model. We make custom drop pipes and 3 feet is typical to begin with.  To get assistance locating the ideal fan for your warehouse, give us a call.

Enhance safety and reduce fire-related fatalities

Sprinklers have been shown to save lives by significantly increasing fire safety within a building. Using ceiling fans should not be interpreted as ruling out the option of sprinkler installation. The most important thing is to follow NFPA 13 regulations, which put everyone's safety first.

The NFPA found that the fatality rate is 12.1 per 1,000 fires in buildings without working smoke detectors or sprinklers In contrast, for buildings with both hardwired alarm systems and sprinklers the rate was only 1.3 per 1,000 fires. This exemplifies the critical role sprinklers play in saving lives.

The article goes on to state that sprinklers have a 96% success rate in putting out flames when they are present and operational.

Due to two main concerns, the NFPA has established rules for HVLS fans and sprinklers:

Obstruction: Whether the presence of a nearby HVLS fan will obstruct the sprinkler system.

Fire Impact: How the air movement caused by HVLS fans might affect the ability of sprinklers to extinguish fires effectively.

Several studies have been conducted to investigate whether HVLS fans have any impact on sprinklers or the ignition point of a building fire.

Case studies

The Air Movement and Control Association International (AMCA International) recently released a report for 2021. They conducted a year-long study focusing on running large-diameter ceiling fans in warehouse spaces during the COVID-19 pandemic. According to the research, using HVLS fans in warehouses helps reduce the number of airborne particles and, in turn, the risk of the virus spreading.

Moreover, the study showed that opening doors and windows could help increase cross-ventilation. The same goes for running HVLS fans in a downward direction. You can combine these two methods to get the most ventilation.

Is it completely safe to use HVLS with sprinklers?

Yes, HVLS are totally safe when used with sprinklers

Two studies looked into how HVLS fans and sprinklers work together during a fire. These studies, conducted separately in 2009 and 2011, found that HVLS fans do not pose a threat to sprinkler systems.

The 2009 study conducted by Schirmer Engineering, found that HVLS fans do not hinder the operation of a sprinkler system. This is true regardless of fan placement. However, the only condition set was that the fans must be installed in accordance with NFPA guidelines. Additionally, the study was unable to find evidence suggesting a negative effect of positioning an HVLS fan directly above the ignition point of a fire.

Moreover, findings from the 2011 study revealed that even with HVLS fans, ESFR sprinkler systems effectively protected storage areas under up to 40 feet high ceilings.

Bottomline

Since air plays a crucial role in fires, the significant airflow generated by HVLS fans raises questions. Hence, it is natural to have concerns about the impact of HVLS fans on sprinkler systems and fires. However, remember that as long as your HVLS fan is constructed and installed in compliance with NFPA 13 guidelines, it will not disrupt sprinkler systems or contribute to the spread of fires.        

For further information regarding the advantages of HVLS fans in large industrial or commercial buildings, we invite you to visit our website. Feel free to contact our friendly AmeriWind staff should you have any concerns or queries.

Using an Ameriwind fan in the winter is a great way to save energy and money while providing a more comfortable environment for your employees. Contact us today at 610-987-0488 to learn more about how we can help you create a custom big fan solution for your space.