Velocity Water Services Blog

Why is Fire Flow Testing Important?

There are many things to consider when we talk about the safety of our cities and communities. Having information about some fire protection practices is essential for making informed decisions when needed. At Velocity Water Services, we strive to be transparent and responsible when we talk to the public about the importance of fire flow testing and additional maintenance to the water supply system. Our services include fire hydrant inspections, maintenance, and repairs in the municipal, private, and industrial sectors.

Sufficient water supply and maintaining water pressure are among the most important factors for firefighting and ensuring the highest standards of water quality. The hydrant system provides both.

A typical hydrant in Canada is not full of water at all times, contrary to what many movies would have you believe, and they will not send a stream of water into the air if hit by a vehicle. Rather, the hydrant is opened with a hydrant wrench to allow the water flow to the fire truck. But how do we make sure that the fire hydrant would work when we need it the most?

What Is Fire Flow Testing, and How Does It Work?

Fire flow testing, also known as hydrant flow testing, is the process of identifying the available fire flow from a hydrant at a predetermined minimum water pressure in the water distribution system (WDS). This test is required for the purpose of identifying the available flow rate from a hydrant, new construction developments, and before installing fire suppression systems. As areas are developed, the added water connection increases water demand to the existing WDS. Fire flow testing is used to understand how this added demand affects the system.

The data provided can be displayed numerically and graphically to better understand the condition and limitations of the WDS. The results can indicate weak points in a water distribution system. They can be used by water and fire departments for the purposes of planning improvements, design extensions to new areas, or the restoration of ageing infrastructure. Several calculations are made to determine the water distribution system's condition. These tests need to be performed by a professional and according to the National Fire Protection Association (NFPA) recommendations.

At Velocity Water Services, we provide fire flow testing services in accordance with NFPA 291. Contact us today to schedule a meeting and discuss how we can help.

How Is the Fire Flow Test Performed?

The fire flow test requires the use of two or more fire hydrants. The first hydrant is generally referred to as the “Test” or “Residual” hydrant, and it collects the results of the static and residual water pressures. The second one, also known as "flow hydrant", is used to obtain the pitot gauge reading. It is important to note that in the event of a fire flow test for the purpose of fire suppression system design, the test hydrant should be as close as possible to the property, and the flow hydrant should be downstream from the first one.

The first step of the test is critical and should not be skipped for safety reasons. It includes a visual inspection of the fire hydrants. Our team looks for any damages or defects that may affect the general working condition of the fire hydrants. If such is found, the identified deficiencies should be repaired before further testing is completed. This includes the locating and testing of the hydrant’s isolation valve to ensure a way to shut the hydrant down in the event of the hydrant becoming inoperable during the fire flow test.

The Two Types of Tests 

We can conclude that there are two types of fire flow testing options:

  • Main Capacity Flow Test is used as a preliminary step for engineers who design water-based fire protection systems. The test measures friction loss in the piping leading to the most remote sprinkler head. It is important to note that this test does not verify the working condition of the first, or also called test- hydrant because it does not flow water.

  • The hydrant capacity test is done by flushing a single hydrant. It measures the water supply available through an individual hydrant. This type of test completes the process of water supply evaluation in terms of fire protection and should be done as an additional step to the main capacity flow test.

The key differences between the two tests above are:

  • The main capacity test is used to identify the water distribution systems condition and abilities.

  • The hydrant capacity test will ONLY identify the condition and abilities of that individual hydrant.

Our team can help you with individual hydrant flushing or fire flow testing. Check the fire flow test available on our website.

What Makes Fire Flow Testing Important?

There are several reasons why fire flow testing is required:

  • First and foremost, the test determines the water availability for fighting a fire.

  • It determines the pressure and flow-producing capabilities at any location within the distribution system.

  • It helps uncover potential water distribution problems, such as closed or partially closed water main valves and heavy-pipe wall deposits.

  • It helps for the evaluation of any system improvements or replacements made.

  • It provides infrastructure condition assessment data, especially when flow rates can be compared to previous year’s results.

  • It determines insurance premiums.

  • The test enables municipalities to colour-code the fire hydrants, depending on their strength of output, and this helps firefighters determine the best approach in case of an emergency.

This is extremely important for the safety of any residential property and for planning, building, or maintaining any commercial or residential structures.

How Often Should Fire Flow Testing Be Done?

Following the NFPA 291, public fire hydrants should be tested every five years and flushed at least annually to verify their good working condition.

It is important to note that in cases where significant water main improvements are made, or large developments have been completed, the five-year rule does not apply, and fire flow testing should still be completed to identify the WDS abilities following the changes.

At Velocity Water Services, we have a proactive approach when it comes to fire hydrant and water distribution maintenance. Our services help clients in their efforts to provide a safe and secure environment for all citizens. based on your needs.

What Could Happen if a Fire Flow Test Is Not Done?

Avoiding regular fire flow tests could cause the inability to fight fire when needed and/or put the quality of water in the WDS at risk. Since this could potentially add to property damages, impact public health, or even cost lives, this testing should be performed on time and with the help of an experienced team.

At Velocity Water Services, we have years of experience, combined with an in-depth knowledge of common issues related to hydrants, so we can help you prevent failure before it occurs. So give us a call to discuss how we can be of service. 

Source:

https://rweng.com/fire-flow-tests-how-why/

https://velocitywaterservices.ca/services/fire-flow-testing.html

https://hosemonster.com/resources/blog/the-single-hydrant-flow-test/

https://www.mtas.tennessee.edu/reference/conducting-fire-flow-test

https://www.qrfs.com/blog/370-nfpa-guidance-on-fire-hydrant-testing/

https://hosemonster.com/resources/blog/nfpa-291-recommended-practice-for-fire-flow-testing-and-marking-of-hydrant/