10 Facts About PEX Pipe You Need to Know

5 min read

red and blue PEX water lines in rough-in stage

Every plumber has their preferred tools, techniques and products when they’re installing or repairing a plumbing system. From pricing to longevity, several factors can dictate what you decide to use on the job.

When it comes to piping, there can be a lot to consider too. As different materials are sunset out of rotation and others face rising costs, PEX tubing has become the go-to for many. Still, there’s a lot of misinformation about the plastic pipe — from health and safety to its approved usage.

To help cut through the noise and give you the facts you need to understand this popular pipe material, we tackle some of the biggest questions about PEX we’ve seen.

Is PEX BPA free?
Is PEX safe for drinking water?
Does PEX leach chemicals?
Are rodents attracted to PEX?
Is PEX safe for hot water?
Is PEX UV resistant?
Can you bury PEX?
Does the color of the PEX matter?
What is the lifespan of PEX?
Is it OK to bend PEX?

Is PEX BPA free?

Yes. NSF/ANSI/CAN 61, a plumbing standard that evaluates the health effects of potable water system components, tests for BPA levels in plastic piping and confirms that it isn’t detected in our PEX pipe.

PEX is made of cross-linked HDPE (high density polyethylene). To make PEX, the molecular structure of polyethylene material is chemically or physically modified so its polymer chains are permanently linked, forming a high-performing pipe suitable for a variety of potable and non-potable plumbing applications.

Is PEX safe for drinking water?

Yes, our PEX-a and PEX-b are both safe for drinking water. Our piping system solutions are all third-party tested through IAPMO or NSF to the following standards:

NSF/ANSI 61 drinking water systems components - health effects. This American standard — established in collaboration credible organizations like the Environmental Protection Agency (EPA) and World Health Organization (WHO) — sets the benchmark criteria for evaluating health effects of many drinking water system components, including plastic piping. Compliance with this standard means that the product is safe for use with drinking water.
NSF/ANSI/CAN 372 drinking water system components – lead content (complies with the lead-free requirements of the U.S. Safe Drinking Water Act). This standard applies to any drinking water system component that conveys or dispenses water for human consumption through drinking or cooking. Compliance with this standard means that the product is considered “lead free.” This standard is consistent with the United States Safe Drinking Water Act (SDWA) and its lead-free plumbing requirements, as well as the requirements of individual U.S. states such as California.
NSF/ANSI 14 plastic piping system components and related materials. This establishes the minimum physical, performance and health effects requirements for plastics piping system components and related materials in non-potable applications.

NSF periodically reassesses chemicals to ensure that existing drinking water criteria are based on the latest science.

Does PEX leach chemicals?

NSF/ANSI/CAN 61 requires “analysis for any chemicals that leach from a material into drinking water and a toxicological evaluation of concentrations leached to ensure that they are below levels that may cause potential adverse human health effects.” SharkBite’s compliance with this standard means our pipe is proven safe for drinking water.

Are rodents attracted to PEX?

No. Research has shown that rodents keep their teeth in good condition by gnawing on things. An array of materials such as wood, copper, lead and all plastics are at risk of chewing if installed in rodent-infested areas.

Is PEX safe for hot water?

Yes, SharkBite PEX is safe for hot water distribution, as it is certified to the following standards.

ASTM F877 standard specification for crosslinked polyethylene (PEX) hot- and cold-water distribution systems. This specification provides requirements and test methods specifically for PEX used in residential and commercial, hot and cold, potable water distribution systems as well as sealed central heating, including under-floor heating systems.
ASTM F876 standard specification for crosslinked polyethylene (PEX) tubing. This specification includes requirements and test methods for material, workmanship, oxidative stability in potable chlorinated water, UV resistance, and more for PEX used in, but not limited to, residential and commercial, hot- and cold-potable water distribution systems, reclaimed water, municipal water service lines and building supply lines. In accordance with ASTM F876, SharkBite PEX tubing complies with the “Excessive Temperature and Pressure Capacity” requirements of 210 F and 150 psi for 720 hours (30 days) to accommodate short-term water heating system malfunctions.

CSA B137.5 crosslinked polyethylene (PEX) tubing systems for pressure applications. This is the Canadian performance and testing specification for PEX used in potable water distribution systems or other applications. It’s similar to ASTM F876.

SharkBite PEX is also chlorine resistant and is certified to meet ASTM F2023 oxidative-resistance requirements for continuous hot water recirculation.

It has a PEX material designation code of 5306. The 5 indicates the highest chlorine resistance rating per ASTM F876. That means we have 100% chlorine resistance when continuously recirculating hot water at 140 F.

Is PEX UV resistant?

Yes, SharkBite PEX-b has a designation of 5306, which denotes a six-month UV resistance — the highest rating available — per ASTM F2657 testing and ASTM F876 evaluation criteria. SharkBite PEX-a also recently received this UV listing. While previous inventory lists a 5106, or one-month UV rating, on the pipe print stream, all new inventory will be marked 5306 to indicate the new level of UV resistance.

Can you bury PEX?

Yes, you can bury SharkBite PEX-a and PEX-b pipe in most applications, as it’s approved to AWWA C904, which covers PEX pipe in regard to burial. Be sure to check with local, city or state codes to see if the pipe needs to have sleeves or any type of protective burial for your area. PEX pipe can be used as a service line based on its corrosion resistance to soil and water, its long life and its oxidative resistance.

Our PEX pipe is not suitable for use in areas where the soil is or may become contaminated, including soil used for backfilling. Soil used for backfilling must be free of rocks, debris or any sharp object that may cause damage to the fitting or pipe through impact or abrasion.

It's also important to note certain fittings must be wrapped for underground burial, so if you’re installing any PEX connections underground, check to see if you’ll need silicone tape to wrap the fitting.

Read more: Using SharkBite Underground

Does the color of the PEX matter?

There are no performance differences between different PEX colors. The color of the pipe is only an indication of hot (red) or cold (blue). White is neutral and does not signify any specific use.

You may notice that PEX-b is colored all the way through, while PEX-a only has a colored outer sleeve. This is simply a difference in manufacturing the results from the way each PEX type is extruded.

What's the lifespan of PEX?

PEX tubing, when operating within its pressure and temperature ratings, has a predicted life expectancy of 50 years per PPI TR-3. Additionally, SharkBite PEX offers the highest-rated chlorine resistance and six-month UV resistance to combat risk of premature failure.

PEX pipe is more resistant to bursting in freezing conditions than metal piping. Because it’s flexible, PEX tubing expands rather than splitting, minimizing costly repairs.

Is it OK to bend PEX?

Yes, you can bend PEX. Its flexibility is one of the main benefits of PEX pipe versus rigid pipe. PEX can often maneuver around corners without the use of elbows or other additional fittings. This reduces the number of connection points, lowers material cost and minimizes potential leaks.