How to Open a Fire Hydrant for a Flow Test: An 8-Step Guide

Opening a fire hydrant for a flow test might sound straightforward, but it’s a process that needs precision and care. 

A fire hydrant flow test is critical for assessing water pressure and flow rates, ensuring that hydrants are fully functional and ready for emergencies. 

But to get an accurate reading and avoid damaging the system, it’s essential to know how to open a fire hydrant properly. Doing it incorrectly can cause damage, disrupt water service, or even lead to fines. 

So, let’s walk through the steps for opening a fire hydrant for a flow test safely and efficiently, ensuring you get it right every time.

Why Knowing How to Open a Fire Hydrant Properly Is Key

Fire hydrants are vital to public safety; however, if they’re not handled properly, you can damage the hydrant or cause problems in the surrounding water system. 

Opening a hydrant incorrectly can lead to water surges that unnecessarily stress pipes or cause flooding. Knowing the proper steps to follow ensures the hydrant works at its best without causing harm.

Conducting a correct hydrant flow test ensures accurate pressure and flow readings. Skipping steps can result in inaccurate data, which may falsely indicate that the water supply is sufficient in an emergency.

How to Open a Fire Hydrant Step-by-Step

Opening a fire hydrant takes more than just turning a knob. Here’s how to do it right:

1. Prepare the Area

First, it’s essential to ensure the area around the hydrant is clear. 

Look out for any obstacles like cars or debris that could obstruct your work, and make sure no bystanders are within 10 feet of the hydrant. This safety zone will help prevent accidents if the water pressure is higher than expected. 

It’s a good idea to wear protective gear such as gloves and safety glasses to shield yourself from debris or water that might spray out. In addition, the nearby drainage system should be checked to avoid any flooding problems during the flow test.

2. Check the Hydrant for Damage

Before opening the hydrant, inspect it closely: check the operating nut, nozzle caps, and other visible parts to ensure everything is intact. 

If there are any leaks or visible damage, it might be best to hold off on the test and notify the appropriate personnel. 

This quick check ensures that the hydrant is safe to use and won’t cause any issues once you start the flow test.

3. Remove the Hydrant Cap

After the safety check is complete, you can remove the cap. Stand behind the hydrant as you loosen the cap using a hydrant wrench, taking care not to damage the threads. 

Avoid using a pipe wrench, which can damage the hydrant’s components. Once the cap is off, be mindful of the exposed threads; they need to remain clean and undamaged to ensure a proper seal when you’re done. 

4. Attach Testing Equipment

After removing the cap, it’s time to set up the equipment for the test; this usually involves attaching a pitot tube or pressure gauge to measure water flow and pressure. 

Make sure the equipment is tightly secured to avoid leaks or inaccurate results. If a gate valve is required to help regulate water flow, connect it now. 

Ensuring everything is adequately attached is critical to getting reliable readings during the test.

5. Slowly Open the Hydrant Valve

Now, you’re ready to open the valve; using the hydrant wrench, slowly turn the valve counterclockwise, about a quarter-turn per second. 

This gradual approach prevents a sudden rush of water, which could cause damage to the hydrant or surrounding infrastructure. 

Keep turning until you’ve completed at least five full rotations, ensuring the drain holes are fully closed and no water leaks underground. As the water flows, monitor the pressure to maintain control.

6. Conduct the Fire Hydrant Flow Test

Once the hydrant is fully open, you can begin the flow test.

Start by measuring the static pressure, which represents the pressure in the system before any water is discharged. Then, measure the residual pressure while the water flows. 

These readings are crucial for understanding the performance of both the hydrant and the water supply system. 

Use your pitot tube or other measuring tools to determine the flow rate in gallons per minute (GPM). This data helps evaluate the hydrant’s readiness in an emergency situation.

7. Slowly Close the Hydrant

After you’ve gathered all the necessary data, it’s time to shut off the hydrant. 

Just as you opened it slowly, you should close it at the same pace: about a quarter-turn per second. This helps prevent water hammer, a sudden surge in pressure that can damage the hydrant or water system. 

Turn the valve clockwise until the water flow slows down and stops completely. Do not force the valve shut, as this could cause unnecessary damage.

8. Replace the Hydrant Cap

With the hydrant now closed, remove your testing equipment and replace the cap on the nozzle. 

Use the hydrant wrench to securely fasten the cap, but be careful not to cross-thread it, which could lead to future problems. 

Tighten the cap snugly to prevent any leaks, but don’t overtighten. Once this is done, your flow test is complete, and the hydrant is back in good condition for future use.

Legal and Environmental Considerations

Opening a hydrant and running a test isn’t as simple as it seems; there are regulations to follow. 

Sticking to these rules helps prevent fines, penalties, and damage to the system or surroundings:

Legal Requirements and Authorization

Fire hydrant operation is strictly regulated, and unauthorized use can have serious consequences. Here’s what you need to know:

• Authorized Personnel Only: Only certified professionals, like firefighters or licensed contractors, should handle hydrant operations. In most jurisdictions (like Milwaukee, WI, or Blue Island, IL), unapproved use is illegal and may incur substantial fines.
• Permit Requirements: Many cities require permits to conduct hydrant flow tests, particularly in non-emergency situations. Ensure you obtain permission from local authorities or water departments before testing.
• Fines for Unauthorized Use: Operating a hydrant without proper authorization or during restricted times can lead to hefty fines. These penalties vary depending on local laws but can reach thousands of dollars.
• Liability for Damages: If a hydrant or water system is damaged during the test, the responsible party can be liable for repair costs and any disruptions caused.

Environmental Protection

Opening a fire hydrant releases a significant amount of water, and managing this discharge properly is essential to minimize environmental impact and avoid flooding. 

Here’s what you must consider:

• Prevent Flooding: Before opening the hydrant, make sure nearby drains are clear to prevent water from pooling or flooding the area. This helps protect surrounding properties and infrastructure.
• Safe Discharge: Direct water flows away from roads, sidewalks, or sensitive areas like gardens. Use hoses or other equipment to safely manage water discharge and minimize erosion or damage to landscaping.
• Water Conservation: In areas experiencing drought or with water restrictions, it’s important to schedule tests when water usage is lower and ensure the test is performed as efficiently as possible to avoid wasting water.

Keep Fire Hydrants Functional and Ready

Performing a fire hydrant flow test correctly starts with knowing how to open the hydrant correctly; this initial step sets the stage for an accurate and safe test. 

In addition, quality equipment is a must for reliable flow test results. That’s where New England Manufacturing LLC excels. Our expertise in manufacturing and distributing high-quality water flow test equipment means you have the tools to get the job done right. 

If you want to perform efficient and accurate hydrant flow tests, our equipment can make all the difference. Reach out today to ensure your tests run smoothly and safely.