11-06 Backflow preventer size

Question: 11-06Code Section: 7Date: 1 March 2011OBC 2012 Reference:;;

Question Submitted:
I have a question as to sizing a RP BFP. This is a commercial building with a 3” water service,
the City has installed an 11/2” meter and the service to the building is reduced to 1”. What size
BFP am I mandated to install.

The BFP should be sized to meet the requirements of the building regardless of what size
meter is installed. The code does not specify the sizes required with relationship to the
distribution system.

However, Sentences, and provide a guideline to determine
the size required.