For plumbing installations in India, where temperatures often reach high levels and there's prolonged exposure to harsh sunlight, plumbing systems are at risk of facing a number of environmental challenges. Extreme climate conditions can affect their durability over time and can sometimes lead to system failure.
CPVC has been installed for over 50 years in hot climates such as South California, 30 years in the Middle East and 20+ years in India. These installations are still performing, fault free, providing healthy clean water to building occupants.
The threat of UV on piping material
The main threat to the integrity of plumbing system applications in hot outdoor climates, with prolonged exposure to sunlight is UV.
UV Light accelerates photo oxidation of polymers. Photo-oxidation is the degradation of a polymer surface in the presence of oxygen or ozone. The effect is facilitated by radiant energy such as UV or artificial light.
Photo-oxidation is a chemical change that reduces the polymer's molecular weight. As a consequence of this change the material becomes more brittle, with a reduction in its tensile, impact and elongation strength.
UV exposure and CPVC pipe
1 Is CPVC pipe UV resistant?
CPVC's composition is 63% Chlorine (derived from common salt) and 37% petroleum. The lower amount of petroleum makes the CPVC piping material very stable.
The Chlorine molecules act as a barrier to UV Light. This prevents oxidation of the hydrocarbon chain, the main cause of degradation in plastics with high petroleum content.
2 CPVC performs even under prolonged UV exposure
Some CPVC additives are prone to UV light; and prolonged contact does lead to slight discolouration. However, the pressure bearing capacity of the pipes is unaffected, even after prolonged UV light exposure.
It is perfectly safe to continue using CPVC pipes, as pressure bearing capabilities and other properties of the pipe remain unaffected by UV exposure.
3 CPVC can be painted in outdoor applications
Pipes can be installed in direct sunlight; however, to limit discoloration, it is recommended to paint the pipes with a compatible latex/water based paint to minimize the impact of UV light on the piping material.
4 CPVC is not polyolefin based plastic pipe
Polyolefin based plastic pipes are extremely prone to chlorine degradation and UV Light accelerates this process, frequently leading to failures. UV light acts as a strong catalyst for the oxidation process within materials such as HDPE, PPR, PEX and PB.
UV light can amplify the inherent incompatibility of material with chlorine and chlorine-based compounds used in water treatment. Many countries including India use Chlorine as a disinfectant for water and hence this increases the chances of failures in polyolefin based plastic pipes.
5 CPVC is impervious to chlorine
CPVC, such as FlowGuard Plus pipes and fittings, is inherently impervious to chlorine. This means chlorine and chlorine based compounds used in water supplies will have no adverse effect on piping, with or without the threat of UV light exposure.
For more information, visit the contact us page to talk to us or any of our high-quality local manufacturers.
Binay Agrawal, a highly experienced and accomplished professional, currently holds the position of Business Head of the TempRite South Asia division at Lubrizol India.