If you’ve ever paid attention to the fire hydrants in your neighborhood, town, or city, you may have noticed that some are differently colored than others. Contrary to popular belief, this design choice is not coincidental or adopted to enhance the aesthetic appeal of firefighting implements (although it certainly does so, which is a great bonus).
In fact, different coloring serves a very specific purpose: to help first responders (and relevant authorities) determine the output power of a fire hydrant at a mere glance. This piece of information can be critical to firefighting efforts, which is why most municipalities encourage contractors to go for color-coded options when searching for hydrants for sale or to perform color-coding post-installment.
But, what do all these different colors mean? That’s what we’re here to find out, so let’s dive in!
Fire hydrants earn their ratings based on two factors: flow rate and pressure. Both parameters are important to know for effective fire suppression, so let’s break them down.
In simpler terms, the higher the flow rate, the more water available to extinguish the fire.
This parameter is critical because it allows firefighting personnel to tailor their strategies for maximum efficiency and effectiveness.
Determining the flow rate is done using a Flow Test which involves opening the fire hydrant, allowing the water to flow freely, and measuring the amount of water discharged over a set period of time.
Adequate pressure not only ensures that the water can travel through the hose(s) but, also, dictates how far the stream can reach, both in terms of distance and height. There are also three types of pressure, all of which are checked during the Flow Test:
Most municipalities in the US color code their hydrants for the reasons mentioned above. The National Fire Protection Association (NFPA) recommends a standardized color scheme for bonnets and nozzle caps to indicate different flow rates, as well as hydrant bodies to indicate to whom the hydrant belongs to, as follows:
Belonging:
Body Color | Supply system |
Chrome Yellow
Chrome Silver White Lime Yellow |
Municipal |
Red | Private |
Violet
Light Purple |
Non-pottable |
Flow Rate:
Bonnet & Nozzle Color | Flow Rate (GPM) | Hydrant Class |
Blue | 1,500+ | AA (Excellent Flow) |
Green | 1,000 – 1,499 | A (Adequate for residential areas) |
Orange | 500 – 999 | B (Marginally adequate) |
Red | Below 500 | C (Inadequate) |
Also known as a “high-flow” or “high-capacity” fire hydrant, a super fire hydrant refers to a unit that can:
These fire hydrants are typically installed in high-risk areas, such as densely populated urban sectors or industrial zones, giving firefighters the most powerful tool to suppress and extinguish fires.
At Blair Supply Corp. you can find different types of fire hydrants, fit for your specific type of project. We partner with the leading manufacturers in the US, renowned for their product quality, longevity, and reliability.
Connect with us today and let our expertise of 60+ years facilitate the success of your project!