Boat Vents | Marine & Boat Vents
Boat vents play important roles on many power boats and sailboats. They are used to ventilate engine and machinery compartments to prevent dangerous buildups of gasoline or diesel fumes and to ensure proper airflow in cabins, consoles, and other enclosed spaces. » Read More
Importance of Vents on a Boat
Whether you are new to boating or not, ventilation is something that you should not take for granted. On a boat, it is not just important for ensuring that you have a comfortable and enjoyable time on the water; it can be a matter of life and death. Proper ventilation is required by law on many boats, so you need to understand the how and why of ventilating your boat.
To help you, here at Boat Outfitters, we have put together this guide to boat ventilation.
Whether you are new to boating or not, ventilation is something that you should not take for granted. On a boat, it is not just important for ensuring that you have a comfortable and enjoyable time on the water; it can be a matter of life and death. Proper ventilation is required by law on many boats, so you need to understand the how and why of ventilating your boat.
To help you, here at Boat Outfitters, we have put together this guide to boat ventilation.
Importance of Fresh Air for Engine Compartment Ventilation
The first legal requirement for boat ventilation was as far back as April 1940 when, by law, all boats powered by gasoline required sufficient ventilation. That law is still in place now.
If you move a few decades forward in time, the law was amended in 1982 to make a distinction between powered ventilation and natural ventilation. Every closed compartment containing a gas engine or gas tank must be ventilated by at least two ventilator ducts, and engine compartments containing a gas engine with a cranking motor must be ventilated by powered exhaust blowers operated from the instrument panel. This latter requirement applies to virtually all gas-powered inboard and sterndrive boats.
In most boats, there is always the risk, whether large or small, that gas fumes can build up. Without the right type of vents or accessories like blower fans, the buildup of fumes becomes dangerous. As well as posing health risks when inhaled, the fumes are also obviously very flammable and explosive.
Outboard-powered boats with permanent fuel tanks that are vented outside the boat are not required to have ventilation systems — unless they have a gas generator on board in an enclosed space. Diesel-powered inboards and sterndrives are also not subject to the ventilation requirement since diesel fumes are not explosive, but most still have systems to ventilate their engine compartments.


Different Types of Boat Vents
There are a variety of different vents for boats available on the market these days. This guide will hopefully shed some light for you on what each is used for, to help you make the right buying decisions for your vessel.
Clamshell Vents
Clamshell vents are so-called because of their shape and design and are normally used as entry points for piping and wiring. They can also be used, thanks to their design, to hide hull fittings like deck drain scuppers and fuel tank vents or the top section of special through-hull vents.
Rounded Louvered Vents
Rounded louvered vents are designed to allow for airflow when venting hoses. While keeping unwanted elements out, they allow air to flow freely.
Mushroom Vents
These are vents that have a curved hood, similar to the top of a mushroom, that is primarily used to regulate air in cabins on the lower deck of boats. Mushroom vents can be adjusted as necessary by being lowered or raised. The mushroom shape helps keep rainwater and spray out while allowing air to flow freely.
Deck Vents
Deck vents, are used to allow air to flow freely through the engine area or room and any cabins on your boat with reducing the amount of sea water, spray and rain in.
Air Suction Vents
Air suction vents are designed to force air in and out of areas that require ventilation.
Cowl Vents
Marine cowl vents are specially designed vents that are normally mounted on the deck and bring air into the bilge or cabin to ensure there is ventilation. When used in combination with Dorade boxes, these vents allow air to travel freely without obstruction, while preventing unwanted water from getting into specific areas.
Thanks to their wide and cleverly-shaped openings, they allow large volumes of air to flow freely and are normally found installed protruding from the boat deck.
Contact us at Boat Outfitters today for any questions when it comes to boat and marine ventilation.
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