I received a call today from a mechanical contractor bidding on a job to review a letter from the state indicating that the plans for a Cat 1 Dental Facility could not be approved until the following changes were made:

1. 2021 NFPA 99 Health Care Facilities Code section 15.3.2.8/5.1.10.11.2.2 Piping underground within buildings or embedded in concrete floors or walls shall be installed in a continuous conduit. Construction details reflect the dental air and vac are buried below the concrete floor. Please provide detail for protection of the piping systems that are buried beneath the building.

2.  2021 NFPA 99 Health Care Facilities Code 15.3.2.2/5.1.4/5.1.4.6.1 Verify zone valve shutoffs locations for dental air and dental vac. Please label the emergency shutoff valves for the other medical gases as zone valves (Line item 3 and 13 on P4).

3. 2021 NFPA 99 9.3.6.5.3.3 Verify mechanical exhaust vent serving cylinder room is within 1 foot of the floor.

4. 2021 NFPA 99 Health Care Facilities Code sections 15.3.2.7/ 5.1.9.1 (9) Verify essential electric requirements are met for dental category 1 medical gas warning systems.

5. 2021 NFPA 99 15.3.2.7(3) Warning systems. Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel. Verify indicator locations for dental air and vac at the source.

There is going to be a Cat 1 WAGD system installed, which will have zone valves.

My question:  Does the dental air and dental vacuum need to be Cat 1?

The dental air piping is being installed under the concrete floor, not "encased in concrete".

Thoughts?