What is the mechanical code rule regarding the minimum outside air intake distance from a plumbing vent

Plain-English answer

Per the International Mechanical Code (IMC Section 401), the open intake louvers of any mechanical outside air system must be located a minimum of 10 feet away horizontally from any plumbing vent stack termination, chimney, or gas appliance exhaust vent. Alternatively, the intake must sit at least 3 feet below the level of that exhaust point if they are located closer together.

Field checklist

• Stop and verify the approved detail, manufacturer instructions, foreman direction, and project specs before touching it.
• Per the International Mechanical Code (IMC Section 401), the open intake louvers of any mechanical outside air system must be located a minimum of 10 feet away horizontally from any...

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