What should be the standard dimension of ventilator in home?

Standard dimensions of a ventilator in Residential Building:

Ventilator moves outdoor air into a building or a room and allows to exit indoor air outside the room. 

Bathroom = 5 feet x 8 feet , a CFM rating of 40

Kitchen = 1 x 2.5 feet

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Std sizes of vents in home

• Kitchen: 1′ x 1½’, 1′ x 2′
• Bedroom: 1′ x 1½’
• Bathroom, W.C.: 1′ x 1½’ = 1½’ x 1′ (Lowers)

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