1700 13TH ST 9TH FLOOR 2022-01-20

June 21, 2019 Mr. Tony Lee Page 2 of 3 Reference: PRMCE 9th Floor. Additional Requested Fire Dampers. "Original" Approved Fire -Fighting Design Concept: o Since the patients are not capable of self-preservation, a "defend -in -place" strategy was approved by the City of Everett, The Everett Fire Marshall, and the Department of Health o With a "defend -in -place" strategy the patients remain in the building during a fire event. The intent is to have the fire department fight (and contain) the fire and smoke while the building is occupied. o During is "fire event" the building systems remain running. The fire alarm system notifies PRMCE of a potential fire event and allows facilities to investigate for a short period of time before the fire department is dispatched (5 minutes comes to mind). o Each patient floor has 3 smoke compartments — North Wing, South Wing; and Connector. Diagram attached. o If needed to protect the patients, occupants will be moved from a zone in alarm into a zone that is not in alarm — but they remain on the floor itself. Both supply air and exhaust air systems will remain in operation. This was found acceptable due to the fact that the system is 100% outside are and there is no possibility of recirculating smoke back into the building. Operation and Safety Concerns to Consider if Fire Dampers are Added in Main Supply Air Duct as Proposed in Design Review: o The fire damper is a mechanical device that is activated by heat melting a fusible link that drops the damper. It does not report back to either the fire alarm system and/or the DDC control system. That means that the hospital will not necessarily know if there is an issue right away. o By the time the damper drops a fire will be fully developed in the room. The room itself does not have a smoke detector (they are in the corridor only). The fire alarm system will not be in alarm yet. o When the dampers drop, the supply air to the zone will be cut off but the exhaust will remain running. This will drive the zone very negative and draw any smoke from the room into the patient areas that are occupied. o The supply air ducts that will be "cutoff' are shown in orange on the attached plans. The exhaust air ducts that remain operational are shown in cyan. Looking at specific airflow numbers yield the following: ■ Zone "A" will be 9,960 CFM negative. ■ Zone "B" (Connector) will be 5,620 CFM negative. The consequence of this is that the smoke will not only be drawn into the occupied part of zone "A" but also into zone "B" which is part of the escape path from the floor. This is illustrated by the purple arrows on the attached plan (reference 4 escape stairs highlighted in blue). Design with community in mind If 020481active120482043ftoe review commentshemo for coe.docx