They have been looking for them on inspections Call the town and ask the inspector that would be the easiest way to find out.

Page 72 of this doc already shared above from the state spells it out clear as day, and trust me, you don’t want to deal with the kind of havoc that water hammer can create in a system.

https://www.mass.gov/doc/248-cmr-10-uniform-state-plumbing-code/download

Water hammers are required by code law in Massachusetts when a dishwasher is being installed.