Boating
Under The Influence (BUI)
It's A Different World On The Water
How Can Boating Under The Influence Affect Me?
Are You Under The Influence?
Other Ways To Enjoy Boating
It's A Different World
On The Water
In the marine environment — motion,
vibration, engine noise, sun, wind, and spray intensify the
effect of alcohol and drugs. These “stressors”
cause fatigue — and dramatically affect a boat operator’s
coordination, judgment, vision, and reaction time.
There’s hidden danger too. Common prescription
medications — like those for heart or blood pressure –
could possibly have side effects that can be multiplied by environmental
stressors. So Boating Under the Influence or BUI is a factor even
for those who don’t drink or use dangerous drugs. If you are
unsure or have questions about your medications, contact your physician.
Levels of blood alcohol or medications that would
have little impact on land can potentially cause a much greater
degree of impairment for the operator of a boat.
That’s one reason BUI is a clearly identified
contributor to approximately 34 percent of fatal boating accidents.
How Can Boating Under The Influence
Affect Me?
- Your peripheral vision, night vision, focus, and
ability to distinguish colors (particularly red and green) diminish.
- Your inner ear can be disturbed, making it impossible
to distinguish up from down if you fall in the water.
- A physical sensation of warmth may make it easier
to fall victim to hypothermia.
- Your cognitive abilities and judgment deteriorate.
- Your balance and coordination are impaired.
- Your reaction time decreases.
A boat operator with a blood alcohol concentration
(BAC) above 0.10 percent is estimated to be more than ten times
as likely to die in a boating accident than a sober operator. Most
states, and the federal government have a BAC limit of .08 percent.
It’s ILLEGAL to operate a boat —
any boat, from a canoe, rowboat, or PWC to the largest vessel
— under the influence of alcohol or dangerous drugs.
The U.S. Coast Guard and local law enforcement agencies cooperate
to enforce stringent state and federal laws. Penalties can
include large fines, suspension or revocation of boat operator
privileges, and even jail terms.
If you are determined to be operating a vessel while
intoxicated, the Coast Guard may board your vessel, arrest you,
detain you, terminate your voyage until you are no longer intoxicated,
or turn you over to state or local authorities.

Are You Under The Influence?
This table shows the approximate impact
of alcohol consumption based on body weight. Remember that
many factors — including waterborne stressors, prescription
medications, and fatigue — can increase the effects.
There is no “safe” threshold for operating a boat!
| APPROXIMATE
BLOOD ALCOHOL PERCENTAGE |
| |
100 |
120 |
140 |
160 |
180 |
200 |
220 |
240 |
|
| 1 |
0.04 |
0.04 |
0.03 |
0.03 |
0.02 |
0.02 |
0.02 |
0.02 |
RARELY |
| 2 |
0.09* |
0.07* |
0.06* |
0.06* |
0.05* |
0.04 |
0.04 |
0.04 |
|
| 3 |
0.13 |
0.11 |
0.09* |
0.08* |
0.07* |
0.07* |
0.06* |
0.06* |
|
| 4 |
0.18 |
0.15 |
0.13 |
0.11 |
0.1 |
0.09* |
0.08* |
0.07* |
POSSIBLY* |
| 5 |
0.22 |
0.18 |
0.16 |
0.14 |
0.12 |
0.11 |
0.1 |
0.09* |
|
| 6 |
0.26 |
0.22 |
0.19 |
0.17 |
0.15 |
0.13 |
0.12 |
0.11 |
|
| 7 |
0.31 |
0.26 |
0.22 |
0.19 |
0.17 |
0.15 |
0.14 |
0.13 |
DEFINITELY |
| 8 |
0.35 |
0.29 |
0.25 |
0.22 |
0.2 |
0.18 |
0.16 |
0.15 |
|
| 9 |
0.4 |
0.33 |
0.28 |
0.25 |
0.22 |
0.2 |
0.18 |
0.17 |
|
| 10 |
0.44 |
0.37 |
0.31 |
0.28 |
0.24 |
0.22 |
0.2 |
0.18 |
|
The asterisk ( * ) indicates estimated levels of impairment that
could mean the individual is possibly influenced.
|
This table gives a guide to the average impact of
alcohol consumption for the number of drinks that are consumed over
a one-hour period.
For more information about boating under the influence
go to the BUI section of
this website.
Other Ways To Enjoy Boating
Remember that cruising, fishing, paddling,
skiing, and other water sports are enjoyable in their own right.
Never use dangerous drugs. Be aware of the effects of certain
prescription medications. And consider these alternatives to
alcohol:
- Consider having no alcohol aboard — intoxicated
passengers are also at risk of injury and falls overboard.
- Take other cool drinks, like sodas, water, iced
tea, lemonade, or other non-alcoholic beverages.
- Bring plenty of food and snacks.
- Wear clothing that will keep you and your passengers
cool in the summer, warm in the winter.
- Limit your trip to avoid fatigue.

|