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§ 18-28-606.2.1 — Return air systems

Municipal Code of Chicago (2026 S-74, current through Council Journal of June 17, 2026) · Municipal Code of Chicago § 18-28-606.2.1

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18-28-606.2.1 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 the space served by the air distribution system is protected by a system of area smoke detectors in accordance with Section 907 of the Chicago Building Code. The area smoke detector system shall comply with Section 18-28-606.4. (Amend Coun. J. 11-9-16, p. 36266, § 36; Amend Coun. J. 4-10-19, p. 100029, Art. XII, § 8; Amend Coun. J. 9-14-21, p. 35949, Art. VI, § 8)