Apr. 22, 2025
When selecting piping systems for potable water applications, safety, durability, and compliance with health standards are non-negotiable. One material that has gained attention in recent years is PERT-AL-PERT pipe (Polyethylene of Raised Temperature Resistance-Aluminum-Polyethylene). But can this multilayer piping solution safely transport drinking water? In this article, we explore the properties, certifications, and suitability of PERT-AL-PERT pipes for potable water systems.
What Is PERT-AL-PERT Pipe?
PERT-AL-PERT pipe is a composite material consisting of three layers:
Inner layer: PERT, a flexible, high-temperature-resistant polyethylene.
Middle layer: Aluminum, which provides structural rigidity and oxygen barrier properties.
Outer layer: PERT, protecting the aluminum from external damage.
This design combines the flexibility of plastic with the strength of metal, making it ideal for hot and cold water distribution, underfloor heating, and gas supply. However, its use for drinking water requires careful evaluation.
Is PERT-AL-PERT Safe for Potable Water?
The short answer is yes, provided the pipe meets specific certifications. Here’s what to consider:
1. Compliance with Health Standards
NSF/ANSI 61 Certification: This is the gold standard for materials contacting drinking water. PERT-AL-PERT pipes must undergo rigorous testing to ensure they don’t leach harmful chemicals (e.g., heavy metals or volatile organic compounds) into the water.
WRAS Approval (UK): Confirms compliance with water safety regulations.
KIWA or DVGW Certifications (Europe): Ensure adherence to regional potable water standards.
Always verify that the manufacturer’s product is explicitly certified for potable water use.
2. Aluminum Layer Safety
The aluminum core in PERT-AL-PERT is fully encapsulated by PERT layers, preventing direct contact between water and metal. This eliminates risks of corrosion or aluminum leaching, provided the pipe remains undamaged.
3. Temperature and Pressure Resistance
PERT-AL-PERT pipes can withstand temperatures up to 95°C (203°F) and pressures of 10 bar, making them suitable for both cold and hot potable water systems. Their thermal stability reduces the risk of bacterial growth (e.g., Legionella) in hot water lines.
Advantages of PERT-AL-PERT for Potable Water
Corrosion Resistance: Unlike metal pipes, PERT-AL-PERT won’t rust or scale, ensuring consistent water quality.
Flexibility: Easy to install in tight spaces without joints, minimizing leak risks.
Longevity: A 50+ year lifespan under proper conditions.
Oxygen Barrier: The aluminum layer prevents oxygen permeation, protecting boilers and heating systems.
Potential Limitations
Cost: More expensive than standard PEX or PVC pipes.
Installation Expertise: Requires specialized tools (e.g, press fittings) and trained technicians.
UV Sensitivity: The outer PERT layer degrades in sunlight; pipes must be shielded during outdoor use.
Installation Best Practices
Use only certified fittings and connectors compatible with PERT-AL-PERT.
Avoid mechanical stress or kinking during installation.
Insulate pipes in areas prone to freezing.
Conduct pressure tests before finalizing the system.
Conclusion: Is PERT-AL-PERT a Good Choice for Drinking Water?
PERT-AL-PERT pipes are a safe and reliable option for potable water when they carry the proper certifications (e.g., NSF/ANSI 61). Their hybrid design offers superior durability and performance compared to traditional materials. However, always:
Source pipes from reputable manufacturers.
Follow local plumbing codes.
Partner with certified installers.
By prioritizing compliance and quality, PERT-AL-PERT can be an excellent investment for residential and commercial drinking water systems.
FAQ Section
Q: Can PERT-AL-PERT pipes be used for both hot and cold water?
A: Yes, their temperature resistance makes them suitable for both applications.
Q: How do I verify if a PERT-AL-PERT pipe is certified?
A: Check for markings like “NSF 61” or “WRAS Approved” on the pipe or consult the manufacturer’s documentation.
Q: Are PERT-AL-PERT pipes recyclable?
A: The aluminum layer complicates recycling, but some manufacturers offer take-back programs.
