A new type of factory-built combination exhaust and intake air fitting is introduced that does not require separation between the two openings. Although this has been approved for the 2021 IBC, it is ONLY for dwelling or sleeping unit mechanical ventilation systems. It is NOT ALLOWED for HAZARDOUS MATERIALS Exhaust Ventilation systems...
2021 IMC 401.4 and 501.3.1 cocentric venting systems
