Let's not confuse readers on this blog........anyone installing or inspecting CPVC plastic pipe needs to read ALL of NFPA 13 Section 6.3.6 AND the applicable appendix text as well as the installation requirements from the various CPVC plastic pipe manufacturers.
NFPA 13 (2007) Section 6.3.6.1 states the following: "Other types of pipe or tube investigated for suitability in automatic sprinkler installations and listed for this service, including but not limited to CPVC and steel, and differing from that provided in Table 6.3.1.1 or Table 6.3.6.1 shall be permitted where installed in accordance with their listing limitations, including installation instructions." ABSOLUTELY nothing about being approved in an "exposed" installation.
Some important excerpts from the Appendix:
-Some listings do provide for the use of exposed piping in conjunction with residential or quick-response sprinklers, but only under specific, limited installation criteria.
-With respect to thermoplastic pipe and fittings, exposure of such piping to elevated temperatures in excess of that for which it has been listed can result in distortion or failure. Accordingly, care must be exercised when locating such systems to ensure that the ambient temperature, including seasonal variations, does not exceed the rated value. The upper service temperature limit of currently listed CPVC sprinkler pipe is 150°F (65.5°C) at 175 psi (12.1 bar). The upper service temperature limit of currently listed polybutylene sprinkler pipe is 120°F (49°C) at 175 psi (12.1 bar).
-Consideration must also be given to the possibility of exposure of the piping to elevated temperatures during a fire. The survival of thermoplastic piping under fire conditions is primarily due to the cooling effect of the discharge from the sprinklers it serves. As this discharge might not occur simultaneously with the rise in ambient temperature and, under some circumstances, can be delayed for periods beyond the tolerance of the piping, protection in the form of a fire-resistant membrane is generally required. Where protection is required, it is described in the listing information for each individual product, and the requirements given must be followed. It is equally important that such protection must be maintained. Removal of, for example, one or more panels in a lay-in ceiling can expose piping in the concealed space to the possibility of failure in the event of a fire. Similarly, the relocation of openings through protective ceilings that expose the pipe to heat, inconsistent with the listing, would place the system in jeopardy. The potential for loss of the protective membrane under earthquake conditions should also be considered.
-While the listings of thermoplastic piping do not prohibit its installation in combustible concealed spaces where the provision of sprinkler protection is not required, and while the statistical record of fire originating in such spaces is low, it should be recognized that the occurrence of a fire in such a space could result in failure of the piping system.
Anyone who reads this (and all of the other pertinent material regarding CPVC piping) and concludes it is OK to install it in an exposed arrangement for a NFPA 13 location is blinded by bias or worse.
Response to the original question: My opinion is that it is pitiful and considered poor engineering design to use CPVC plastic piping for the drain lines when the remainder of the system is steel.........If I were the customer or a consultant for the customer, I would suggest they find a more professional and reputable sprinkler contractor for any future projects AND I would not recommend a contractor who cuts corners such as this........what other corners will a contractor like this cut in an attempt to maximize profit or retain a job as the "lowest bidder". We need to act like professionals and install systems that will function properly over the long haul (50+ years rather than being so focused on a quick profit and hope the system will last for 5-10 years).
