PVC is forbidden for use in tap pipes and can only be used on sewers. Using PVC as the air supply duct of the fresh air system, is there any harm, will it pollute the indoor air?
In the central fresh air installation, the layout and installation of the pipeline plays a pivotal role. Nowadays, the installation of the fresh air system, many companies use PVC pipes, the advantages are: no rust, corrosion resistance, light weight, easy to handle installation, because the cost It is inexpensive, so it is widely used in installations such as renovation and fresh air central systems.
It can be used theoretically. If the resin used in PVC pipe is food grade or medical grade, it can be used.
PVC pipes must be added with stabilizers during the production process, but the stabilizers are classified as non-toxic and toxic. Only the addition of toxic stabilizers such as lead salts can cause harm. PVC pipes on the market are mixed, and some small companies use lead salts as stabilizers, and it is difficult to reach the relevant cleaning standards.
Plasticizers are generally toxic additives and plasticizers used in the food industry are non-toxic. Heat stabilizers are lead salts and calcium zinc. Lead salts are toxic, while calcium and zinc are non-toxic. So some PVCs are toxic, while others are non-toxic (food grade and medical grade). Ordinary PVC-U pipes in China are all toxic (except food grade and medical grade). Therefore, owners who choose inferior PVC-U pipes to install fresh air need to pay attention.
CCTV has also been exposed in the past two years. The ratio of some good PVC pipe materials and recycled materials bought in the market is 80%+20%. The new materials can only be customized at the factory. In order to make the new material and the recycled material better blend, the product will be whitened, and the fusion agent and whitening agent will be added. If the new material is small and the recycled material is much, the added fusion agent and whitening agent will increase.