BobNH
Considerations of CPVC pipe include:
- Generally limited to 1/2" to 2" Copper Pipe Size
- Some complaints of "plastic taste" in water
- Fittings and pipe subject to cracking or damage on job site if dropped or stepped on
- Solvents used to join fittings and pipe contain volatile organic compounds (VOCs) which are known pollutants and require proper ventilation during installation
- Subject to melting during a fire (becomes viscous at 395° F)
- High coefficient of expansivity (1 inch in 50 feet over 50-degree temperature change) (3.4x10-5 in/in/°F)
- Inner CPVC pipe surface can support the growth of bacteria including legionellae pneumophilia (ref. A Comparison of the Colonization by Bacteria of Copper and Other Materials Commonly Used in Plumbing Systems with Special Reference to Legionella Pneumophila)
- Due to ease of installation, CPVC is sometimes installed by less skilled labor, potentially resulting in more frequent incidence of improper workmanship.
- Subject to cracking during earthquakes
- Generally requires a 24-hour cure period before pressurizing with water
Standards and code compliance (eg. FlowGuard Gold®)
- Meets or exceeds ANSI/NSF Standard 61 for potable water
- Meets of exceeds all ASTM and industry standards
- Meets model building codes, BOCA National Plumbing Code, National Standard Plumbing Code, Standard Plumbing Code, Uniform Plumbing Code, CABO 1- and 2-Family Dwelling Code, Canadian Plumbing Code
Health Effects of CPVC
Much has been written about the potential health effects of residual vinyl chloride monomer, or RVCM which is found in trace amounts in plastics containing Polyvinyl Chloride, including CPVC and PVC pipe. Proponents and detractors alike continue to debate the long-term health impact due to extended exposure to RVCM. VCM is made by heating ethylene dichlroride (EDC) to 700 degrees F in the presence of oxygen. VCM is used to produce PVC resins which are used to make pipe and other materials using a process known as polymerization. During this process, most, but not all of the VCM is consumed. Trace amounts remain trapped in the PVC resin where it either outgasses into the atmosphere, or migrates into food or drink stored in containers or pipes made of PVC. This remaining chemical is residual vinyl chloride monomer, or RVCM.
For the record, all national building codes have approved CPVC for potable water distribution in the United States and Canada. These approvals have come after extensive testing and quality control standards which guide the production of these products. Today's product meets stringent ANSI/NSF-61 standards for water quality control. There is no scientific evidence that CPVC tubing made to current US standards is in any way harmful to health.
However, there is little argument that extended exposure to VCMs which exceed government standards, can lead to neurological and liver effects as well as cancer, such as angiosarcoma - a normally rare form of liver cancer. As long ago as 1961, Dow Chemical researchers concluded that exposure to Vinyl Chloride levels greater than 50 ppm were considered potentially dangerous.
Generally, high exposure levels of VCM have been historically limited to workers who produced CPVC and PVC products on a daily basis. In some cases, there have been increased incidences of rare illnesses clustered in areas near manufacturing facilities using vinyl chlorides. The shroud of secrecy surrounding VCM broke when, on January 23, 1974, B.F. Goodrich responsibly reported that it had traced three fatal cases of angiosarcoma among workers at its Louisville, Kentucky plant.
In a 1998 Houston Chronicle article by Jim Morris called "Toxic Secrecy," the ill effects of long-term exposure to VCM is well documented. Furthermore, the US Environmental Protection Agency (EPA) produced a revised fact sheet on January 27, 1998 on Vinyl Chloride as part of the National Primary Drinking Water Regulations.
The EPA report, which is intended to be an unbiased information source, states that "vinyl chloride [can] potentially cause neurological effects from acute exposure at levels of 0.002 mg/L."
"Drinking water levels with are considered 'safe' for short-term exposures: For a 1--kg (22 lb.) child consuming 1 liter of water per day: a one- to ten-day exposure of 3 mg/L; upto a 7-year exposure to 0.01 mg/L."
"Major human exposure will be from inhalation of occupational atmospheres and from ingestion of contaminated food and drinking water which has come into contact with polyvinyl chloride packaging materials or pipe which has not been treated adequately to remove residual monomer."
Granular activated charcoal and packed towared aeration are considered the best technologies available for treatment of water containing RVCM.
Other findings reveal that extended exposure to VCM has been linked to a hand disability called acroosterolysis, although this has been generally limited to people who routinely cleaned production reactors. It should be noted, however, that according to ASTM Standard F402-88--and underscored by the Plastic Pipes and Fittings Association (PPFA) User Bulletin 8-82--gloves should be worn when handling CPVC pipe, although many installers fail to follow these guidelines or are unaware of them.
In addition, an unusual level of brain cancer was reported between 1951 and 1977, including astrocytoma and glioblastoma, at one manfacturer, although the manufacturer denies any conclusive linking.
Today, the production of CPVC pipe is strictly regulated. NSF (National Sanitation Foundation), a public non-profit organization dedicated to public health and safety, audits many manufacturers of plastic pipe including CPVC, PVC, acrylonitrile-butadiene-styrene (ABS), polyethylene (PE), and cross-linked polyethylene (PEX).
Products with the NSF certification are tested in accordance with NSF Standard 61. PVC and CPVC pipe is tested twice annually for RVCM, ensuring that production samples remain below established maximum allowable levels. Products with the NSF-pw certification are further tested for compliance with all other properties, including health-related.
Therefore, if CPVC is contemplated for use in any structure for a potable water supply, it is critical that the product is NSF certified. Most codes make this a requirement, but it is no guarantee that the contractor has followed these guidelines when purchasing materials. Imported products from other regions outside the US may not meet these guidelines and could pose a health risk over time.
Specifying CPVC Pipe (example)
All hot and cold water plumbing pipe shall be manufactured from a Type IV, Grade I Chlorinated Polyvinyl Chloride (CPVC) compound with a Cell Classification of 23447-B per ASTM D1784. The pipe shall be manufactured in strict compliance with ASTM D2846 to SDR 11 Copper Tube Size (CTS) specifications, consistently meeting or exceeding the quality assurance requirements of this standard. All CPVC CTS pipe shall be packaged immediately after its manufacture to prevent damage, and shall be stored indoors at the manufacturing site until shipped from the factory. The pipe shall be manufactured in the USA by an ISO 9002 certified manufacturer, and shall carry the National Sanitation Foundation (NSF) seal of approval for potable water applications, meeting section NSF 14 and 61 water standards.
Give it time, someone will now turn to copper and try to bash its use now. Patiently wait as this always happens..
the idea is to change the original poster's mind from using his preferred piping method like is being displayed, heavily.