Sentinel Public Safety Center

A new public-safety building that brings a police department and a fire service under one roof: dispatch, an emergency operations training room, records, investigations, patrol and briefing areas, police and fire offices, fire-crew dormitories, a kitchen, dining and day room and a fitness room, with the IT, electrical and elevator rooms that keep it all running. A building like this never closes, so the spaces run on very different schedules — dispatch and the dorms around the clock, the training room only when it is booked — and each needs its own comfort control and outdoor air. The same goes for power and water: dispatch and the IT room cannot lose power when the utility does, and the fire crew needs hot water for showers at any hour. It is a design-build project, designed to the 2025 California codes and Title 24, and issued at the 90% design development stage.

We set the mechanical design up zone by zone, so each part of the building can run on its own schedule. Rooftop: 15 packaged single-zone heat pump units with return fans — one or two for each major area, from dispatch (two units, so one can carry the room if the other is down) to the training room, records, investigations, patrol, briefing and the police and fire offices — each with an outdoor-airflow monitoring station, a temperature-based economizer with Title 24 compliant controls, two-stage compressors, acoustically lined isolation curbs and factory start-up coordinated with the controls contractor. Outdoor air: three dedicated rooftop units that supply 100% outdoor air. Offices and dorms: a variable refrigerant flow system with two condensing units serving about twenty ducted and cassette fan coils, so each fire-crew dorm room and office has its own control. Technology rooms: about a dozen ductless split systems for the IT, electrical and elevator machine rooms, which need cooling all year whatever the rest of the building is doing. Plus ceiling fans for the kitchen, dining and day room and the fitness room, an infrared heater, and the duct and pipe insulation and refrigerant pipe schedules. The set carries the mechanical legends, general notes, the CALGreen non-residential mandatory measures and the Title 24 mechanical mandatory measures, so the contractor and the plan checker work from the same rules. Electrical: power distribution from the main switchboard to panels across the building, with a power connection for every rooftop unit, outdoor-air unit, VRF and split system; a standby generator with automatic transfer switches, so dispatch, the IT room, the emergency operations training room and life-safety loads stay on through a utility outage, and UPS power for the dispatch consoles and the network equipment so they ride through the seconds before the generator takes over; LED lighting with Title 24 controls (occupancy and vacancy sensors, daylight dimming and automatic shut-off), dimmable low-glare lighting in dispatch, and low-level night lighting in the dorm corridors; shore-power drops for the fire apparatus in the bays; and EV-capable parking to CALGreen. Plumbing: domestic cold and hot water with backflow prevention at the service, and water heating sized for crew showers at any hour and for the kitchen; water-efficient fixtures to CALGreen; sanitary drainage and venting, with a grease interceptor for the kitchen; trench drains in the apparatus bay piped through a sand and oil interceptor; a decontamination area for turnout gear with an emergency shower and eyewash; and roof drainage with overflow drains, plus condensate drains from the rooftop units.