Range hood ducting

Does anyone know of good articles stating why hoods must be ducted outside. I know sop says so and I truly understand why but sometimes an article written by a third party puts the point across to a client or RE agent better.

© Range exhaust vent. The inspector shall
report as Deficient:
(2) a vent pipe that does not terminate
outside the structure, if the unit is not of a recirculating
type or configuration;

SOP states that only if vented, needs to be to the outside. Some jurisdictions require hoods to be vented, but most cities allow recirculating as well.

IBC 2006

**SECTION M1503 RANGE HOODS **

**M1503.1 General. **

Range hoods shall discharge to the outdoors through a single-wall duct. The duct serving the hood shall have a smooth interior surface, shall be air tight and shall be equipped with a backdraft damper. Ducts serving range hoods shall not terminate in an attic or crawl space or areas inside the building.

Exception: Where installed in accordance with the manufacturer’s installation instructions, and where mechanical or natural ventilation is otherwise provided, listed and labeled ductless range hoods shall not be required to discharge to the outdoors.