Selecting the right PVC pipe is critical for the longevity and safety of any plumbing, irrigation, or industrial system. Two of the most crucial yet sometimes overlooked specifications are pressure rating and UV resistance. This checklist will guide you through these vital factors to ensure a smart, durable purchase.

First, understand Pressure Rating (PN). This indicates the maximum water pressure the pipe can handle continuously. Common ratings include PN 6, PN 10, and PN 16. For underground mains or high-rise building supply, a higher rating like PN 16 is non-negotiable. Always choose a pipe whose pressure rating exceeds the system's maximum operating pressure by a safety margin. Check not only the pipe but also the fittings—they must match the pipe's rating. Ignoring this can lead to catastrophic failures, leaks, and costly water damage.

Second, assess UV Resistance. Standard white PVC pipes undergo photodegradation when exposed to sunlight, becoming brittle and losing impact strength. For any above-ground application, you must specify UV-stabilized PVC. These pipes are often manufactured with compounds like titanium dioxide or carbon black (making them grey) to absorb UV radiation. Look for markings like "UV resistant" or "sunlight resistant." Never use standard, non-stabilized PVC outdoors without proper insulation or painting with a latex-based paint formulated for plastic.

Your action checklist:

1. Determine maximum system pressure; add a 25-50% safety factor.

2. Select pipe and fittings with a pressure rating (PN) above your calculated value.

3. Identify the installation environment: buried, indoors, or exposed to sunlight.

4. For UV exposure, insist on certified UV-resistant PVC pipe from the supplier.

5. Verify all specifications by physically checking pipe markings for ASTM standards (e.g., D1785 for pressure pipes) and manufacturer stamps.

By meticulously verifying pressure rating and UV resistance, you invest in a system that delivers performance, avoids premature replacement, and ensures project integrity. This proactive approach saves significant time and resources, making it the hallmark of a professional installation.