In the Dec. 2007 issue of PM Engineer, I took the International Code Council (ICC) to task for not appointing a representative of the American Society of Plumbing Engineers (ASPE) to the Plumbing Code Change Committee. Well, I was wrong. ICC did, in fact, appoint an ASPE representative to the Plumbing Code Committee. So, my sincere apologies to ICC for writing such nasty words.
My comments were based on the initial posting on the ICC Website. Yes, I was informed by the ICC that there were corrections that were being made. Hence, I should have waited. I will admit to being overzealous in my attempt to support ASPE.
You, the readers, deserve accurate reporting of the facts. I failed you in my reporting last month. I will continue to do my best to never repeat this mistake. Again, my apologies.
Besides ASPE, this important committee has representatives from Plumbing-Heating-Cooling Contractors Association (PHCC), the United Association (UA), Plumbing Manufacturers Institute (PMI), NSF Intl., and National Association of Home Builders (NAHB).
All are excellent selections.
Code ChangesOnce again, the ASPE Legislative Committee submitted a number of code changes to the International Plumbing Code. As usual, all of the ASPE changes are very good and should be approved.
ASPE resubmitted their change to add a single stack venting system to the code. Last year, the change was rejected because the Committee believed there were already enough venting options in the code. It failed to pass by nine votes at the Annual Meeting. ASPE pointed out in the code change that the other two model plumbing codes - IAPMO Uniform Plumbing Code and the PHCC National Standard Plumbing Code - have requirements on single stack venting systems. Only the IPC has not accepted the code change. Another change that was submitted by ASPE addresses secondary drainage for a storm drainage system. A similar change was submitted to the IAPMO Uniform Plumbing Code and accepted in that code.
The change would allow three options for secondary drainage. One option would be the use of scuppers or an open-sided roof. The second method would be an independent piping system. The final option would be a secondary system that combines with the primary system. When a combined piping system is selected, the rainfall rate would have to be doubled for sizing the pipe.
The Metal Building Manufacturers Association submitted a change to the storm drainage section to add a sizing method for rectangular downspouts and conductors. The code currently only addresses circular piping arrangements. However, there are many metal buildings constructed with rectangular conductors. The proposed sizing method is conservative in nature, but it would provide a means of sizing the conductors.
ASPE submitted a proposal to reference the new ASPE Plumbing Engineering Design Standard 45 on siphonic roof drainage. This standard provides the methods for sizing a siphonic roof drainage system. This is another change that IAPMO has already recommended for acceptance in the Uniform Plumbing Code.
The remaining code change proposed by ASPE to the IPC would modify the water supply table. This table lists the minimum flow rate and pressure required for each type of fixture. This change would result in an increase in pressure for a number of fixtures and flush valves. There would be a reduction in flow for a urinal flush valve and a blowout water closet flush valve. The change also would add requirements for a bathtub and bidet thermostatic mixing valve.
There is an interesting change proposed to the requirements for space heating with domestic hot water. The change raises the concern about the growth of Legionella pneumophilia in space heating systems. When the temperature is lowered for floor heating systems, the growth of Legionella pneumophilia escalates significantly. The change would require the fluid in the radiant system to be isolated from the domestic hot water and heated with a heat exchanger.
Once again, there are a number of code changes proposed to the grease interceptor requirements.
The two changes that will impact engineering design the most are proposals to prohibit the discharge of food waste grinders to indoor grease interceptors. Food waste grinders would still be permitted to discharge to large outdoor grease interceptors.
The code change hearings will take place the last week of February and first week of March in Palm Springs, CA. The code change can be downloaded from the ICC Web site, www.iccsafe.org. Next month, I will cover the changes to the Mechanical and Fuel Gas Code.