Fire Hydrant System

Fire is one of the most dangerous and damaging things ever to exist, bringing your years of hard work to ashes. In addition to destroying your property, it can also put the lives of your loved ones at risk. Therefore, opting for a fire hydrant system, whether it’s in your residential or industrial space, is non-negotiable. However, small spaces are still easy to cater to with the right fire extinguisher, but when it comes to escalated fires, it’s hard. That’s why the concept of hydrants system are introduced to tackle the escalated wild fires with sufficient supply of water.

The presence of an installed hydrant system makes the work of firefighters easy and quick to control the fire with ease. These are valve-controlled pieces of equipment that are installed with above-ground connections and points installed on a pressurized water supply. A fire hydrant system is a perfectly handy equipment for emergency responders, as it provides a sufficient supply of water. In this comprehensive blog, you will learn about the hydrant system, how they work, and its color coding setup.

Fire Hydrants and Their Pivotal Role in Fire Emergencies

The main reasons why fire hydrants play a pivotal role in fire protection systems are as follows:

• Immediate water supply: If a hydrant is in good condition, water is supplied within a few seconds of opening the valve, meaning that there is no need for pumping, drafting, or waiting for tankers.
• Large volume of water flow: The capacity of hydrants ranges from 500 GPM to 2,500 GPM, based on their class and type, which defines the capacity for suppression.
• Stability and predictability: Hydrants are not portable but remain stationary, making them easily identifiable for firefighters as a reliable source of water.
• Legal and insurance compliance: The NFPA 24 standard requires that all facilities comply with the hydrant requirements in order to obtain operating permits and insurance coverage.

Note | NFPA 25: According to NFPA 25 (Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems), fire hydrants should be inspected annually. They should undergo flow testing within a period of five years, unless the local AHJ requests otherwise.

How It Operates: Working Principle of the Hydrant System

Understanding the fire hydrant system shouldn’t be optional knowledge for HSE professionals who are our protectors during fire emergencies. Even trained and acknowledged professionals fumble when seeing the fire aggressively destroying and the urgency to work quickly. It happens because of their lack of mechanical knowledge, which is pretty straightforward, but every step matters. Let’s understand the working principle and mechanism of it.

The Basic Working Principle of Fire Hydrant System

The fire hydrants work on the very simple pressure delivery model itself. That means its body is connected to an underground water source, and it becomes the main supply. From where this water can be used and controlled, keeping it safe and under constant pressure for use. Generally, by the Municipal or by the facility water distribution system, such designs are available with SpectraFire.

Therefore, when this pressurized water flows upward through the barrel and out through the discharge outlets (nozzle caps). The place where the hoses or pumping equipment are attached to withdraw water. The sequence of the steps from standby to water delivery is a clear mechanical chain.

1. Operating Nut Engagement

A hydrant wrench is used to turn the pentagon-shaped operating nut present on the bonnet part of the hydrant. The operating nut has a connection with the stem, which controls the action of the main valve.

2. Stem Rotation

With the operating nut turned anticlockwise, the stem gets moved down in the barrel, and the total number of turns required will differ from company to company, but normally it requires between 8 and 16 turns.

3. Main Valve Opening

The stem makes the main valve leave its place so that it can allow water from the supply main to enter the barrel.

4. Water Fills the Barrel

In dry barrel hydrants, water rises in the barrel from the bottom upwards. In the case of wet barrel hydrants, there is always water inside the barrel under static pressure.

5. Discharge Through Outlets

The water discharges through the outlets that correspond to nozzle caps that are unscrewed and coupled with the hose couplings. Water flow rate depends on main line pressure, hydrant diameter, and how many nozzles operate simultaneously.

6. Valve Closure And Drainage

With clockwise operation of the operating nut, the valve closes, which results in automatic opening of a drain in dry barrel hydrants for draining water left in the barrel.

NFPA Color Coding System: Understand What Color Means Here

Color Coding on the fire hydrant system isn’t just a mere coincidence we saw, but it’s a tactical way of informing water capacity. By just looking at the color, the firefighters understand how much water a hydrant system holds. It helps easy identification from a distance and ensures the right decision is made before they connect a line. Meanwhile, if this information is misread or the color dates, it also causes significant consequences on the fireground.

The NFPA 291 Color grading practice, which is a Recommended Practice for Fire Flow Testing and Marking of Hydrants, is established. These are used in North America and internationally only to provide reference. It uses two separate color signals on each hydrant, let’s understand which one and how.

The barrel (body) color signifies the water source type that the system is supplying the hydrant.

• Chrome Yellow: Municipal water supply hydrant (standard water supplied by the municipal water system).
• Red: Private water supply hydrant (water supplied by the private system of the facility – tank, pump, or separate main).
• Violet/Pale Purple: Non-drinking water supply (treated waste water, lake water, etc.).

Second come the bonnets and caps, whose color indicates the available flow rate. The expected volume of water from the hydrants is based on the delivery testing and marking. These are the tactically critical colors for fire crews:

It’s Time to Wrap Things Up!

Fire is hazardous, but not understanding and implementing the fire safety rules is our fault. Therefore, having a fire hydrant system if you own a large space, or an industrial area, a commercial area, or even being the management head of societies puts you in the responsibility to install these fire hydrant systems without fail.

Therefore, you should not waste any time and connect with SpectraFire, a leading manufacturer and supplier of fire safety tools. We can get you to set up the fire hydrant system in your locality in no time. Additionally, tailored solutions can also be prepared upon request. We will evaluate your premises to ensure tailored solutions fit and cover more area.

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