N.Y.C. Admin. Code § MC 606: Section MC 606: Smoke Detection Systems Control

606.1 Controls required.

Air distribution systems shall be equipped with smoke detectors listed and labeled for installation in air distribution systems, as required by this section. Duct smoke detectors shall comply with UL 268A. Other smoke detectors shall comply with UL 268.

606.2 Where required.

Smoke detectors shall be installed where indicated in Sections 606.2.1 through 606.2.4.

606.2.1 Return air systems.

Smoke detectors shall be installed in return air systems with a design capacity greater than 2,000 cfm (0.9 m

3

/s), in the return air duct or plenum upstream of any filters, exhaust air connections, outdoor air connections, or decontamination equipment and appliances.

Exception: Smoke detectors are not required in the return air system where all portions of the building served by the air distribution system are protected by area smoke detectors connected to a fire alarm system in accordance with the New York City Building Code. The area smoke detection system shall comply with Section 606.4.

606.2.2 Common supply and return air systems.

Where multiple air-handling systems share common supply or return air ducts or plenums with a combined design capacity greater than 2,000 cfm (0.9 m

3

/s), the return air system shall be provided with smoke detectors in accordance with Section 606.2.1.

Exception: Individual smoke detectors shall not be required for each fan-powered terminal unit, provided that such units do not have an individual design capacity greater than 2,000 cfm (0.9 m

3

/s) and will be shut down by activation of one of the following:

1. Smoke detectors required by Sections 606.2.1 and 606.2.3.

2. An approved area smoke detector system located in the return air plenum serving such units.

3. An area smoke detector system as prescribed in the exception to Section 606.2.1.

In all cases, the smoke detectors shall comply with Sections 606.4 and 606.4.1.

606.2.3 Return air risers.

Where return air risers serve two or more stories and serve any portion of a return air system having a design capacity greater than 15,000 cfm (7.1 m

3

/s), smoke detectors shall be installed at each story. Such smoke detectors shall be located upstream of the connection between the return air riser and any air ducts or plenums.

606.2.4 Supply air systems.

Smoke detectors listed for use in air distribution systems shall be installed downstream of the air filters and upstream of any branch connections in air supply systems having a capacity greater than 2,000 cfm (0.9 m

3

/s).

606.3 Installation.

Smoke detectors required by this section shall be installed in accordance with the New York City Electrical Code. The required smoke detectors shall be installed to monitor the entire airflow conveyed by the system. Access shall be provided to smoke detectors for inspection and maintenance.

606.4 Controls operation.

Upon activation, the smoke detectors shall shut down all operational capabilities of the air distribution systems serving the affected areas in accordance with the listing and labeling of appliances used in the system. Air distribution systems that are part of a smoke control system shall switch to the smoke control mode upon activation of a detector.

606.4.1 Supervision.

The duct smoke detectors shall be connected to a fire alarm system where a fire alarm system is required by Section 907.2 of the New York City Building Code. The actuation of a duct smoke detector shall activate a visible and audible alarm signal at a constantly attended location.

Exceptions:

1. The alarm signal at a constantly attended location is not required where the duct smoke detector activates the building's alarm-indicating appliances.

2. In occupancies not required to be equipped with a fire alarm system, actuation of either area or duct smoke detector shall activate a visible and an audible alarm signal in an approved location. Additionally, duct smoke detector trouble conditions shall activate a visible or audible alarm signal in an approved location and shall be identified as air duct detector trouble.

606.4.2 Fan shutdown for recirculating air systems.

When any building or floor is provided with an air system designed to use recirculated air and is protected by an automatic sprinkler system or an automatic fire alarm system, the fans recirculating air serving the affected area shall automatically stop when sprinkler water flow or a fire condition is detected in the area. For the purposes of this section, 100 percent outdoor air systems shall not be considered recirculating systems.

Exceptions:

1. Activation of a manual pull station shall not be required to automatically stop the fans.

2. Systems having a capacity of 2,000 cfm (0.9 m

3

/s) or less or serving not more than one floor.

3. In Group R-2 and R-3 occupancies with energy recovery systems complying with Section 514.4 and not serving public corridors.

606.4.3 Manual restart of fans after automatic fire detecting device or fire alarm system shut down.

Fans or fan systems which have been automatically shut down on activation of an automatic fire detecting device or fire alarm system shall be arranged and equipped so that they do not automatically restart when either the automatic fire detecting device or fire alarm system is reset. The manual means of restarting the fans or fan system shall function independently from the manual resetting of either the automatic fire detecting device or fire alarm system.

606.5 Manual control.

Manual controls of fans shall be provided in accordance with Section 405.2.