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§ 18-28-401.5.1.5 — Relief openings

Municipal Code of Chicago (2026 S-74, current through Council Journal of June 17, 2026) · Municipal Code of Chicago § 18-28-401.5.1.5

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18-28-401.5.1.5 Relief openings.

Relief openings (RO) as used in Table 18-28-403.3 as set out in Section 18-28-403.3, shall be considered to be any duct that connects a room to the outside. Relief openings for ductwork shall be of sufficient cross sectional area so that maximum velocity shall not exceed 800 feet per minute. Relief openings in ducts for exhaust may extend in a horizontal direction for a distance not to exceed 5 feet.