Watch a slide show Presentation on Flotation.  After watching the slide show close the page and pick from the following list.

An article in Boating Magazine July 22, 2014; Sinking Boats For Safety

Select from the following list:

Level Flotation : Mono-hulled boats under 20 feet in length, with outboards greater than 2 HP.

Modified Level Flotation : Mono-hulled boats under 20 feet in length, with 2 HP or less, or manually propelled.

Basic Flotation : Mono-hull inboard motorboats under 20 feet in length.

 

Why are small boats required to have flotation, and why are there different requirements.?

Back in the 50's and 60's the old Boating Industry Association (now NMMA) and the Yacht Safety Bureau (now ABYC) realized that one of the main reasons people died in boat accidents was the boat sank out from under them. Sounds obvious but it wasn't really.  Then in the 1970's a lot of research was done into hypothermia, and the two came together. It was realized that if the boat did not sink, it would give the people something to hang onto, that could be seen much better than just a head sticking out of the water, and if the boat, although full of water, did not sink, or roll over, then the people could actually stay in the boat. Most of their torso would be out of the water reducing the effects of hypothermia, and providing a much better rescue platform.

So work started on developing a standard for flotation.  Through testing and experiments techniques were developed that would provide enough flotation to keep a small boat afloat, and floating relatively level. However, this did not work well for inboard boats, because the size and weight of the engines required far too much flotation material to float the boat level.

Meanwhile the Federal Boat Safety Act passed in 1971 and went into effect in 1972. The Coast Guard began collecting statistical data on boating accidents.  Analysis of this data revealed that the most significant contributors to fatalities were capsize, sinking and falls overboard. Flotation in a boat could eliminate the sinking, prevent capsizing, and prevent some of the falls overboard.  Many of the "falls overboard" were actually the boat rolling over and dumping everyone into the water. Also analysis revealed that by far the majority of these accidents occurred in monohulled boats under 20 feet in length, manually propelled or with outboard power. The inboards contributed some.

So between NMMA, ABYC, and the Coast Guard it was determined that monohull boats under 20 feet with outboard power or manually propelled should have level flotation, and inboard boats basic flotation.  Basic flotation simply keeps the boat afloat with some of the boat sticking out of the water.

When the regulation was proposed many people in the classic and wooden boat community felt that the standard was too rigid to be applicable to small manually propelled boats or boats with tiny engines.  So after testing and consultation with persons building these types of boats the standard was modified to allow some latitude in achieving the same performance.  That is, these boats have to float level to the same degree as larger boats with bigger outboards, but the method of achieving it is different. It was called modified level flotation. Additionally this small boats are allowed to carry a greater percentage of their weight capacity as persons, than larger boats are. This seemed to satisfy everyone.

This particular standard has been a rousing success in preventing deaths.  It is not clear and probably not quantifiable just how many deaths have been prevented but the fatalities have dropped dramatically since 1972, from about 19 per 100,000 boat, or about 1300 people, to less than 6 per 100,000 boats, about 600, annually in 2005.  At the same time the boating population has grown to roughly 5 times what it was then. The drop in fatalities is a combined result of education, engineering and enforcement, so it is hard to say which has contributed more, but certainly flotation standards have had an effect.

As of July 31 2024 Mudboats and Airboats are no longer granted an exemption from the safe loading and flotation regulations.  The following is a quote from the Fall 2024 Boating Safety Circular: https://uscgboating.org/library/boating-safety-circulars/Boating-Safety-Circular-Fall-2024.pdf

"Reminder, the Coast Guard stopped approving exemptions for floatation requirements on mudboats and airboats, and as of July 31, 2024 all previously approved exemptions for these boats have expired. Manufacturers of mudboats and airboats must now ensure their boats meet the requirements found in 33 CFR 183 Subchapter F and/or G. In 2022 the Coast Guard determined it is no longer appropriate to grant these exemptions, and therefore decided to discontinue the practice. Manufacturers who already possessed exemptions for these boats were granted one last exemption through the conclusion of model year 2024, which ended on July 31, 2024. If you have any questions about compliance with floatation regulations, we recommend you consult the floatation section of the Boatbuilder’s Handbook, which can be found here: https://safeafloat.com/wpcontent/uploads/2021/04/F-_-G-_-HFlotation-Final-4-14.pdf If you require further assistance after reviewing the Boatbuilder’s Handbook, please send an email requesting assistance to rbscompliance@uscg.mil and a member of CG-BSX-23 will be happy to help.

Other Standards:  Standards for Electric Propulsion boats, for Flotation, Safe Loading and Maximum Horsepower Ratings.

The U.S. Coast Guard has published a policy letter regarding standards for Flotation, Safe Loading and Maximum Horsepower ratings on boats with electric propulsion. Essentially the policy letter says that manufacturers of electric propulsion recreational boats should comply with the same standards for Safe Loading, Flotation, and Safe horsepower as gasoline powered recreational boats,  and refers to ABYC Standard E-13 Lithium Batteries and E-30 Electric Propulsion Systems for Boats with Electric Propulsion. The policy letter can be seen at the Coast Guard's website at https://safeafloat.com/wp-content/uploads/2022/08/BSX-23-Electric-Propulsion-Policy-FINAL.pdf

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