Interesting that fire and explosion are so common, and that faulty DC
wiring (typically low voltage) is a frequent cause of boat fires:


BOATU.S. LIST OF TOP INSURANCE CLAIMS

While you may never expect to file an insurance claim on your boat,
knowing why and how damages occur can help you reduce your chances.
The January 2006 issue of Seaworthy, the damage avoidance newsletter
from BoatU.S. Marine Insurance, reviewed five years of its own claim
files to find the most common causes for insurance claims. Both the
individual number of claims, as well as insurance claim dollar amounts,
were factored in to compile the list.

#9: Theft of equipment: Make time-consuming "work" for a thief, and
they will likely go elsewhere. The theft of outdrives can be prevented
by adding hefty locking nuts; the same goes for outboards and trailers.
If they can be removed, expensive electronics should be stored under
lock and key - and at home in winter. Well-lighted storage or marina
facilities with security measures are the best deterrence.

#8: Theft of boat: When thieves steal boats, they often strip
everything of value leaving only a shell. Ninety percent of the boats
stolen were on trailers, so removing tires, installing a coupler lock
and parking in a well lit, secure area can help.

#7: Lightning: Since there isn't anything you can do to prevent a
lightning strike, the best measure to mitigate damage is to ensure your
boat has a proper bonding system that will direct the strike to ground.

#6: Grounding: What you do after you've hit bottom - such as attempting
to power through - often causes more damage than the initial impact.
It's best to stop, carefully evaluate the situation, wait for the tide
or call for help if you need a gentle pull. Also, knowing the exact
depth beneath your depthsounder's transducer and its exact position
relative to the bottom or your boat or running gear is very important.

#5: Collisions: Collisions with docks or pilings are common but
collisions with other boats are more serious. Inattention, blind spots
and too much speed most often are the culprit. Out on the water,
misunderstandings of the rules of the road are most often cited, but
know that it takes two skippers to be in one bad spot at the same time.

#4: Wind and weather: Sloppy weather happens everywhere. Minimizing
windage, tying up securely, guarding against chafe and staying
protected help reduce storm damage.

#3: Fire and explosion: The number one reason for boat fires is DC
wiring faults, with the most common fault being chafed wires, usually
as the result of poor support or insecure attachment. AC shorepower
cord inlets are another prime area as wear and corrosion cause
resistance, which creates a lot of heat. Corroded, overheated exhaust
manifolds and fuel leaks bring up the bottom of the list.

#2: Sinking: Lesser fittings like hoses and clamps only last a few
years and often fail long before the beefy seacock they are attached
to. Outdrive bellows over five years old are on borrowed time and
rainwater improperly drained into the bilge by clogged scuppers kills
your battery and bilge pump.

#1: Striking submerged objects: Nationwide, striking a submerged object
is the most common incident that leads to filing a claim. The amount
of floating debris increases after major storms or extreme tides so be
extra vigilant after these events. Unfortunately, striking an object
sometimes leads to a sunken boat claim; check the bilge immediately
after a strike and frequently thereafter.

If you live in a hurricane prone state, hurricane damage also ranks
high when you factor the dollar amount of each individual claim -
hurricanes cause significant salvage and repair bills. Before the 2006
season starts, have a hurricane plan in place that spells out every
precaution. You can go to http://www.BoatUS.com/hurricanes to get
started with a free hurricane preparation worksheet