Water from the garden hose can easily get out of control any time of the day. If you don’t turn off the pipe or it is leaked or broken at some point, the water can run more than required. Loosing too much can make you look like-
The one thing you need to control this outbreak is a garden hose backflow preventer.
An introduction to the garden Hose Backflow Preventer
City water mains are the key source of water for most households and other buildings including the Fire Protection system. This water can sometimes be stagnant which is not safe for drinking thus not recommended. To solve this, water authorities demand that property vendors fix backflow preventers in their buildings to prevent the mixture of stagnant water with treated water.
This article deeply explains what backflow preventers are, their different types and how they work. Before this, we need to know what a backflow is to get a better understanding of the backflow preventers.
Being a highly useful and potable resource, a vast amount of water is wasted and improperly treated. Stagnant water fills the pipes in wet fire protection systems, making it improper for drinking purposes. It is highly polluted, leading to various water-borne diseases.
Therefore, to prevent water loss, the city government has set up owners to install garden hose backflow preventers to keep stagnant water from mixing portable, cleaned drinking water in the city water supply pipelines. This given blog is all about the usage and working of garden hose backflow preventers.
What is garden hose backflow?
Water flowing in households, other buildings, irrigation units, and plumbing areas from the main water stream supply should flow in one direction. However, due to pressure changes, this water can sometimes flow back into the main supply stream. This can mostly happen during low-pressure times.
The low pressure can occur in the fire hydrant or the water main break thus interrupting the normal flow of water from the main supply to other buildings.
This backflow is dangerous and sometimes fatal as it can contaminate the public drinking supply with harmful impurities like human waste, fertilizers, pesticides, and other hazardous chemicals.
For example, in 2010 there was a case of backflow in Kentucky elementary school where a contractor caused antifreeze chemical glycol to flow backward into the school main drinking supply. As a result of this, the students at Bowling Green suffered from nausea and other infections.
These cases can be deadly but they also bring about other problems. Backflow incidents are expensive to fix. According to the Environmental Protection Agency (EPA), the average cost of fixing backflow cases is $14,800 at approximately 500 hours.
What are garden hose backflow preventers?
It’s a device essential for maintaining unidirectional water flow in supply lines and fire protections, from the main lines to supply pipes.
Several types of garden hose backflow preventer exist, and the most common assemblies include:
1. Reduced pressure zones (RPZ)
It is the most complex and reliable garden hose backflow preventer. RPZ is essential for building internal systems such as plumbing or fire protection. In fire protection supply lines, these are used widely during the leakage of antifreeze or corrosion inhibitors.
RPZ is considered full proof due to the presence of a bidirectional check valve and a hydraulically operated relief valve. It is usually comprised of a shut-off valve near the inlet, dual loaded check valves made of spring and separated by a valve that works via differentiating pressure gradients, four cocks used for testing, and a shut-off valve at the outlet.
2. Double check valves:
It is used in fire sprinkler systems. It is composed of an upstream shut-off valve, 2 independently working spring-loaded valves, 4 test cocks, and a downstream shut-off valve.
3. pressure Vaccum beakers:
PVBs are specifically designed for lawn irrigation, cheap, designed, easiest installment, maintenance, and repair.
Why Are garden Hose water Back Flow So alarming In a Fire Sprinkler System?
To push large volumes of water in fire safety systems such as sprinklers, standpipes, activated sprinkler heads, or pipes is quite needed. In stagnant water, bacteria can foster, converting sprinkled water into a thick black, smelly debris that causes serious illnesses if flows reversely. There is a tremendous contamination risk posing humans to serious health hazards.
Why do you need Garden Hose Backflow Preventer?
To minimize the probability of water contamination going back reversely into GARDEN HOSE.
Pressure drop as a result of municipal pump issues or when a fire hydrant is used can create a siphon in your garden hose and push water, contaminants, chemicals, and debris into the water due to backflow.
Back rush of water can occur as a result of chemical injectors and spray nozzles. The faucet running stops the flow of water by a nozzle. But a large amount of water usage such as washing machines and flushing toilets pulls the water back from hose into municipal water storage sites.
Air trapping can force BACK FLOW of WATER via garden hose backflow preventer.
Here are the 10 best garden hose backflow preventers to buy!
Working Of A Garden Hose Backflow Preventer:
The RPZ valve design works best with a relief valve opening if either of the check valves declines. This results in the dumping of water into the building unless, in the meantime, it is resolved via RPZ garden hose backflow preventer.
One way and check valves in a series arrangement prevent water from getting into the supply line in fire protection systems. One way valve allowing unidirectional flow is a safety asset.
Double-check valve installed in the 1950s for fire protection agencies ensures protection even if the one-way valve fails. This setup enables the closure of one-way valve reducing pressure gradient and ensuring reliable seal off and minor leakage prevention. Whenever pressure in the property area exceeds the city side’s pressure, both redundant valves close, limiting water’s backflow. Though the DCV system being quite sustainable can fail if contaminated or debris enter the valve, failing the valve to close completely.
RPZ being quite similar to DCV, has an additional protective factor: a hydraulically operated relief valve below the first check valve enforces it to be fail-safe.
If, in any case, water leaks via check valves, relief valves open and divert water outside instead of backward pushing so that no backflow occurs.
RPZ, while being more reliable, faces much higher pressure and volume losses than double check assemblies. For RPZ to work, proper drainage must be provided via a relief valve.
Are Garden Hose Backflow Preventers Required On Fire protection Systems?
The code’s main aim is the attachment of installment and ITM requirements to sustain the backflow of water.
Reverse backflow water testing was eliminated from NFPA 25 in 2011. As backflow is a legitimate concern for NFPA, still it considers its prevention outside the scope of NFPA 25. NFPA assumes that its local or state responsibility to ensure backflow.
Garden hose backflow preventers are a prerequisite for working in many systems for fire protection and safety; however, its mandatory setup is put up by necessary local codes generated to prescribed for plumbing enforced by municipalities, water purveyors, and plumbing inspector for the provision of potable drinking water.
Backflow prevention is an overall community need. It’s essential to recognize the risk of cross-connection among wet building systems and city water for a serious water backflow. Water purveyors require proper testing and working of backflow preventers by professionals to ensure reliability and proper functioning.
Each area and society requires specific features and requirements for garden hose backflow preventers:
The (AWWA) American Water Works Association supports and curtails codes essential for model working by offering guidance for when, how for the installment of garden hose backflow preventers based on the level of hazards put forward by fire security and safety system.
Cross-connection with minimal hazards might give rise to nuisance or be aesthetically detrimental if there is a backflow incident, but for sure, it will not cause any health hazard.
Unprotected cross-connections with high hazard involve a substance that can ultimately lead to a severe illness or death if introduced into city water supply lines.
If it happens or in these situations, RPZ is most recommended.
Some relevant facts and information regarding garden hose backflow preventers:
- Factors causing back pressure include sudden outbursts of downstream pressure such as in heating tanks or pressure generators
- Common usage and application of dual valve assemblies include reducing the hazard risk, preventing pollution, and contaminating potable and non-potable water resources.
- Concerns regarding contamination of potable drinking water via pollutants and irritants from fire safety management are: fire systems being constructed by black iron pipes uncoated are considered best and suitable for plumbing. However, higher authorities and organizations do not accept this as a genuine material for water and sewerage system piping and construction material.
- To protect foreign material’s direct connection with potable systems and water storage sites, assemblies of double check valves are widely used, and this does not pose any health risk.
- A protective agent called vacuum pressure breakers is used as a protection against back pressures.
- Hose bib vacuum cleaners are small, cheap devices still attached to cocks, threads, and faucets and are possibly connected to a hose with the highest chance of facing contamination. One important thing is that they must not be utilized or planted in areas or systems under continuous pressure.
- Atmospheric vacuum breaker used only in connections with a non-potable system where the breaker already has a minimum chance of facing backpressure. It must be installed at sites with the discharge system being close to the last control valve. It must be planted above the usage point and should never be used under continuous pressure conditions.
- Also read- Artificial Turf Rake-Quick Review For Best Turf Rakes In 2020
To ensure garden hose backflow prevention in your fire protection systems, make sure to keep backflow keys, tools, and toolsets in check.
After being acquainted with all the pros, working methods, models, and important points regarding safety and hazards, we hope you will like the product and use it. It’s sustainable, easy to use, and install. Moreover, it eliminates water contamination chances and declines health hazards associated with pollutants leaking from fire systems. Garden hose backflow preventer is a highly efficient, sustainable, recommendable, and eco-friendly device.
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