How Chlorine and FlowGuard® CPVC Work Together To Provide Clean, Safe Water

The most important chemical in creating clean, potable water? Chlorine.

A study by Scientific American shows how chlorine and chlorine-based compounds “kills a large variety of microbial waterborne pathogens” and is “widely credited with virtually eliminating outbreaks of waterborne disease in the United States and other developed countries”. The graph below shows a decline of typhoid fever since the introduction of chlorine:

So, to varying extents, the water supply in your home will carry a certain level of chlorine. While that means your water is safe, it can also cause problems—specifically, corrosion of the materials that carry it.

How Chlorine Causes Corrosion of Piping Materials

Chlorine has impressive effects on microbial bacteria in water supplies, but its effects are equally (and adversely) as strong on certain piping materials such as PPR.

When chlorine is added to water for disinfection, it transforms into hypochlorous acid–which is a strong oxidizer capable of breaking chemical bonds.

The problem with using PPR to carry potable water is that its chemical backbone is surrounded by small hydrogen molecules. These molecules are essentially useless in defending against hypochlorous acid. The acid breaks right through, corroding the pipe. Flakes of the plastic start to fall off the inside of the pipe, lowering the systems water pressure and clogging the system.

Lately, these effects are multiplied by the recent introduction of chlorine dioxide (a modified form of chlorine) to disinfect water supplies. While it doesn’t produce by-products or carcinogens, it is more persistent in the water and will emit free radicals that can destroy piping systems using PPR.

Why CPVC Piping is Chlorine Resistant

Unlike PPR, CPVC is naturally resistant to the effects of chlorine and chlorine dioxide used to disinfect potable water supplies.

Instead of the hydrogen molecules that surround the backbone of other plastics, CPVC is protected by large chlorine molecules. Extensive exposure to chlorinated water flows will have little to no effect or corrosion on the piping.

FlowGuard^® CPVC Keeps Water Safe

FlowGuard CPVC is capable of handling the chlorine and chlorine dioxide present in potable water supplies far better than PPR. Owners of FlowGuard piping systems can rest assured that water treatment facilities use of chlorine to disinfect the water supply will not have any affect on their plumbing systems.

CPVC is also naturally resistant to microbial buildup. Its surface is smooth, leaving little for harmful bacterias to latch onto. This means that not only is CPVC resistant to chlorinated water flows, but it also needs less chlorine to remain sanitary.

Finally, FlowGuard CPVC is listed for use in potable water supplies and residential plumbing applications by major international agencies including NSF International, KiWA and WRAS.

For questions about using FlowGuard CPVC in residential plumbing systems, contact our team of piping systems consultants.