Is it the intent of section 1003.3.1 to PROHIBIT a dishwasher from wasting into a grease waste piping system if the dishwasher has a pre-rinse sink?
Similarly, does 1003.3.1 prohibit a hand wash sink located within the kitchen from wasting into the grease waste system?
Interpretation #9497
Published February 24, 2026
Original Request
- Code Version
- 2023
- Code
- PLUMBING
- Code Description
- Chapter
- 10
- Section
- 1003.3.1
- Topic
- Grease Interceptor Approved Listings
Question
Answer Published 02/20/2026 at 2:05 PM
No. Please see the attached commentary
Commentary
Prerinse sinks are specifically listed in 1003.3.1. Dishwashers without prerinse sinks are also listed; both should be connected. The hand sink, as is not listed, may or may not be required to be connected, dependent on Building Official's examination of documents provided. From the commentary, "The Building Official has the responsibility to define the fixtures and equipment and their intended uses that constitute the need for grease interception." As well, any local utilities requirements that would be above code required should be considered.