Have you ever wondered why Schedule 40 PVC is the standard for radon system suction and exhaust piping? I’ll tell you: it’s readily available and very durable even after UV exposure. This is what’s most important when selecting radon mitigation materials. Radon gas, a class A carcinogen, must not leak out of your radon system. Lesser materials like schedule 20, green or even black piping have shown to be less durable during the life of a radon system. Schedule 20 pipe in particular can shatter like glass in cold climates after very little time in the sun: rendering your radon system useless.
PVC or poly vinyl chloride is quite toxic–especially during manufacturing, which has lead us to look for more sustainable solutions for our industry.
PETG, or Polyethylene terephthalate glycol, is a common manufacturing product in 3D printing. At PDS, we asked our resident expert—Shane Barr—with Alpha86 why he chose this material. He replied earnestly, “I suppose the main point being that both materials have their use. The advantage of PETG, in our case, being the adaptability and the allowance of more feasible and safe production. That then allows new and innovative products to come to market with few of the concerns of producing in PVC. There is more ability with PETG to innovate, with no overall drawback, as it can be used much more safely without the need for purpose built ventilation and machinery, thereby expanding the audience and means of production that can utilize the material effectively. The difference in UV resistance is really only applicable in thin films.”
Shane’s comments echoed what I found in my own research. PETG is durable and can be manufactured in a home setting. 3D printing–in general–allows for very little production waste. Design flaws can be fixed immediately without the need to dispose of vast quantities of unusable products. Misprints or other errors can often be recycled back into new materials or samples.
PETG is often used in the medical and food industries due to its ease of use and less toxic qualities. PETG has no BPA or toxic odors or fumes. This protects the manufacturer during production.
PETG also meets ANSI AARST SGM-SF-2023 Standard. Section 6.2.5 allows for: “other light-duty rigid materials of appropriate durability…no less than equal to the commercial durability of existing downspout materials.” In short, PETG can be used anywhere on the exhaust side of a radon system. Flanges and other accessories that are not part of the ASD system are allowed as well. The only unclear use is in suction side applications above grade. Alpha86 is exploring explicit exemptions for future suction side inline designs–however, there is currently no need for these products. All Alpha86 products are tested for tightness and durability before commercial sales production.
Although it allows for PETG, Exception 2 was written with metal fittings in mind. Steel and aluminum are incredible building materials and infinitely recyclable. Many radon systems that exhaust to metal downspout for a clean aesthetic look are inadvertently using a less toxic, more sustainable approach to system design as well. At PDS we prefer steel as it’s more durable, especially to hail damage. See our many fittings and adapters to downspout here.
Overall, as Shane said, both PETG & PVC have their use and both are suitable for radon mitigation systems. Metal can be used on the exhaust and is a very sustainable mitigation material. Check your system for leaks periodically using a smoke bottle and always be sure to test. View our full list of maintenance tips here.
