09-04 Number of trap seals per primer tube

Question: 09-04Code Section: 7Date: 2 March 2009OBC 2006 Reference: 7.4.5.5.

Question submitted: Regarding trap seal primers, The manufactures are quite clear when you use a mechanical device that you can only use one device for one trap. When the plumbers use a manual trap seal primer can they join more than one trap on the sediment faucet, which of course would be protected from backflow with a vacuum breaker.

OBC 2006: 7.4.5.5. Question Submitted: March 2, 2009

7.4.5.5. Trap Seals (1) Provision shall be made for maintaining the trap seal of a floor drain or a hub drain by the use of a trap seal primer, by using the drain as a receptacle for an indirectly connected drinking fountain, or by equally effective means. (2) Where a mechanical device is installed to furnish water to a trap, the pipe or tube conveying water from the device to the trap shall be at least 3/8 in. inside diameter

1. The code is not specific about the number of trap seal primers that can be supplied by one mechanical device. Mechanical devices should be installed as per the manufacturer’s instructions and that might dictate the maximum number of traps that could be serviced from that particular device.

2. A hose bib installed strictly for the purpose of priming the floor drains and this would be in compliance with 7.4.5.5.(1)…provision shall be made…, but is not a method that most municipalities will be willing to accept since the usage to serve as the trap seal cannot be verified or policed.

Interpretation: Approved at AMES 2009