CPVC piping in automatic sprinkler systems

CPVC (chlorinated polyvinyl chloride) piping may be found in the sprinkler systems of light hazard occupancies such as condominium, apartments, residences, or offices. CPVC piping when properly installed in automatic sprinkler systems can reduce installation costs while providing a high level of protection. Use of CPVC piping in these situations is acceptable according to National Fire Protection Association (NFPA) standards.

However, there are concerns with the use of this piping in automatic sprinkler systems. Proper installation, inspection and maintenance are extremely important, as pipe failure can result in significant water damage to the building and its contents.

Common causes of pipe failure include:

• Improper adhesives
• Excessive adhesive use
• Improper solvent applications
• Improper CPVC and steel piping connections
• Construction material exposure, such as:
  • Foam fireproofing overspray
  • Incompatible fire stopping around the pipe
  • Antimicrobial lining used inside some steel pipe
  • Incompatible sealant pastes applied to the threads on sprinkler heads

The use of improper adhesives, excessive use of adhesives, solvents, solvent vapors trapped inside the piping, and exterior hydrocarbon exposure can turn the piping and fittings brittle to the point of failure.

Due to the potential for water damage and business interruption, Nationwide Loss Control Services recommends following the NFPA standard for 5-year inspection with the addition of hydrostatic testing of the CVPC piping. This standard includes internal and exterior inspections; however, we recommend the addition of hydrostatic testing of CPVC sprinkler system piping as part of this inspection.