As someone indicated you COULD calculate a good approximation of the actual C-factor but you should do that for each of the pipe sizes and oh yea since the corrosion can vary depending on things like ambient temperature and air/water interface, you should also calculate the C- factor for each of those different environmental variables.
I think I would do a simple visual inspection in enough locations to ensure that the piping is fully open and stick with the modified C- factor provided by NFPA 13. There is information out there for modifying the C-factor for UNDERGROUND but why would you extend the same philosophy to above ground pipe. UNderground pipe can be: 100+ years old is subjected to tuberculation so granted the surface gets rougher but more critical is the reduction in the internal diameter a tad harder to inspect to ensure it is fully open Roland On Apr 20, 2010, at 3:12 PM, [email protected] wrote: > Can someone tell me were in NFPA-13 dose it talk about the C-Factor > for pipe. I am doing a calc. on an old system and I know I have to > change the C-Factor but I can not find it in the code book. I found > it somewere elese and it says in old pipe i must change the C-Factor > like new black pipe for wet systems will be 120 C-Factor but if its > 50 years old I must chage it to 90. Can someone tell me were to > find this info. Thank You > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) > _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
