Under the combination-plumbing-fixture exception in unamended 2021 IPC Section 1002.1, which compartment geometry permits a combination fixture to use one trap?
- No compartment more than6 inches deeper than another, with waste outlets no more than30 inches apart
- BA depth difference up to12 inches, with outlets up to60 inches apart
- CAny dimensions if the fixture is inside a dwelling
- DNo dimensions qualify because each compartment always needs a separate trap
Where to look it up
https://www.ncosfm.gov/b-1-2024-ncpc/open
Why A is correct
The combination-fixture exception requires both dimensional conditions: at most 6 inches difference in compartment depth and at most 30 inches between waste outlets. This does not establish that every commercial-kitchen installation can use continuous waste; other applicable waste-connection requirements still matter. The NC-added allowance for up to three similar fixtures is not relied on here. See PDF p.139. Source: 2021 IPC model base text reproduced in NC OSFM comparison document, https://www.ncosfm.gov/b-1-2024-ncpc/open