Electrical Shock Hazards—Warning Fact Sheet
Each year swimmers, boaters and people in marinas are injured or killed by electrical accidents. These occur because of wiring problems, component failures or the use of improper equipment when bringing 120 volt or 120.240 volt AC shorepower on board boats. Virtually all of these accidents are avoidable.
While AC electrical power is potentially deadly in any location, it is especially dangerous in and around the water. If there is a problem with the marina wiring, your boat’s wiring or its shorepower cord, contacting concrete or metal docks or the water itself can cause electrical shock. Handling shorepower cords when you are barefoot increases the chance of being electrocuted.
Electricity cannot be detected without the use of specialized test equipment. It may be present on metallic objects such as marina electrical equipment and shorepower connectors or even in the water itself. Contact with electrically energized equipment may result in painful shock, burns, muscle contraction or paralysis, loss of breathing and even stopping of the heart.
Electricity may be present in the water in places where boats are connected to shorepower or where marina wiring is defective. Electricity in the water will generally paralyze swimmers to the point where they lose muscle control, cannot swim and then drown. In a few cases the electrical “field” has been strong enough to cause electrocution from cardiac arrest. The possibility of either of these occurring is greater in fresh than in salt water.
What To Do
- NEVER swim in a marina or in other areas where boats are connected to shorepower.
- Be sure shorepower cords and adapters are in good condition. When in doubt, replace them or have them repaired by a qualified marine electrician.
- Do not use “homemade” adapters or shorepower cords. Purchase and use only products that are “factory” assembled by a recognized manufacturer. Read and follow the manufacturer’s instructions and warnings.
- Always wear “rubber” soled shoes (such as deck shoes or tennis shoes) when handling electrical equipment. Try to avoid touching other metallic objects when working with shorepower cords.
- If a boat inspection or repair requires a person to be in the water, disconnect the boat and all nearby boats from shorepower. Before entering the water check the water for the presence of electricity with a voltmeter or other test equipment. [PHOTO]
When connecting to shorepower:
- Shorepower cords and adapters must be clean and dry before use. If they are dropped overboard, do not use until allowed to dry and then checked by a qualified marine electrician. Keep shorepower inlet covers tightly closed when not in use.
- Get permission from the marina before connecting to a dock receptacle and ask if the “polarity” and ground are correct and when they were last checked.
- Make certain there are no swimmers in the water around your slip.
- Before connecting the shorepower cord, turn off both the boat’s main AC circuit breaker and the dock breaker.
- Connect the shorepower cord at the boat first, then connect the cord to the dock receptacle and turn on the dock breaker.
- Check the boat’s “polarity” alarm or light (if it has one) on the AC panel as soon as the dock breaker is turned on. If the polarity is incorrect, shut the dock breaker off and disconnect the dock end of the shorepower cord immediately. Report the problem to the marina. The marina should contact a qualified electrician to make correction.
When disconnecting from shorepower:
- Shut off the boat’s main AC circuit breaker, then turn off the dock breaker. Disconnect the dock end of the shorepower cord first.
- Disconnect the shorepower cord at the boat receptacle.
- Clean and dry the shorepower cord. Store in a dry location on board the boat.
Once a year, have a qualified marina electrician perform the following:
- Verify the integrity of the boat’s entire AC shorepower grounding system, including the connection to the DC system negative.
- Verify that any galvanic isolators (if installed in your boat) meet current American Boat & Yacht Council (ABYC) standards and are fully functional.
- Inspect shorepower cords, adapters and boat receptacles for any signs of deterioration, including cord wear, loose connections, signs of sparking or overheating and bent or pitted blades. If there are any such signs, examine, correct and test the equipment or replace it.
- Operate the boat’s electrical system at full load (everything on) and check for AC system leakage or voltage between the boat’s underwater fittings (bonding system, if equipped) and the shoreside AC system ground.
Warning—Water and electricity do not mix!
- Swim in marinas
- Alter shorepower connectors
- Use “homemade” adapters or cordsets
- Connect to a receptacle with a different configuration than the plug[/lists]
In the event of an in-water (or onboard) electrical accident:
- Turn off (or unplug) the power to all boats in the area immediately (only then is it safe for others to effect rescue)
- Remove the victim from the water
- Summon help
- If needed, begin rescue breathing or CPR (as appropriate)