• Grill islands must be vented. We require at least two 20 sq. inch vents on an island. Propane vents should be lower on the island because the gas will settle to the bottom.• The vents should be placed across from each other and must have access to outside/fresh air.• Proper ventilation will allow the heat inside of your grill body to escape and prevent any gas from building up from a possible leak in tank or improper gas connection.• Cart models are fully vented.