Lightning Safety on Boats

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When it comes to lightning safety on boats, you have a few choices. You can buy and install lightning rods, sparking electrodes, Faraday cages, and grounding plates to prevent a potential strike. These options are not all suitable for every boat, but you should have a plan and use one if you have any doubts. Read on to learn more about these options. Listed below are some of the most common lightning safety devices for boats.

Lightning rods

A good way to ground a boat is to install lightning rods. These devices are connected to the hull using a heavy two-gauge wire. The rods should extend at least one foot outside of the hull, and they should be attached to the hull’s grounding plate. Boats with cast iron or lead keels or large, flat decks should also install grounding conductors. Boats that are built with two masts are recommended to install two grounding conductors.

A common lightning strike can easily destroy your vessel. Fortunately, lightning rods can help prevent side flashes from occurring. They act as a grounding system, which helps protect your boat and its occupants. This method is also more cost-effective than the other methods of protecting your boat. There are several types of lightning rods, each with a different purpose. In most cases, lightning rods are installed near the bow, where most strikes occur.

Sparking electrodes

Lightning is one of the most frequent hazards on ships. This is largely due to the troubling weather and waters that surround ships. However, lightning incidents can be even more dangerous because of the potential for loose electrical outbreaks and short circuit incidents, both of which can be life-threatening. Sparking electrodes for lightning safety on boats can help protect the ship from both these problems. The following article will examine the various methods that can be used to protect ships from lightning.

Bonding systems are installed in the critical elements. Bonding arrangements vary for each vessel type. Bonding screw installations differ between bulk carriers and oil tankers. A simple silicon or bronze screw electrode is a better conductor than air, so it can help protect the structure of a boat. Another option is to bond large metal objects together with conducting wires. This will equalize their electrical potentials. If lightning encounters a boat, it will bounce off the boat, causing sideflashes.

Faraday cages

The National Fire Protection Association, along with the American Boat and Yacht Council, devised a lightning protection system for boats. This system uses a metal or wire band around the entire boat. The metal band should be placed below the water line and above the mast base. Some boat manufacturers install Faraday cage bands in the hull. Copper bands are attached to wires and are installed at the bow and stern of the boat, ideally above the highest points on the vessel.

Besides installing a Faraday cage, boaters must also be aware of the dangers associated with lightning. A lightning strike involves a sudden change in electric current and a powerful magnetic field. The electro-magnetic pulse that is generated from a lightning strike readily induces currents in neighboring wiring. Even if there is no electrical connection on the boat, the electrical current can fry the electronics on board.

Grounding plates

Boats with electrical systems should install a grounding plate. This plate should be at least one square foot and mounted below the waterline on the exterior of the hull. The grounding plate is electrically connected to the boat’s electrical system with copper strapping and down-conductor wiring. The strapping connects to the plate’s through-bolts. The plate should be in contact with the water during rest.

A lightning strike can create a large amount of current. The high current may also cause voltage surges on nearby wires and equipment. To protect your equipment from these surges, it is crucial to install a grounding plate. You can easily install an air terminal to your mast or tower with a little work. You can also install a grounding plate that looks like an antenna. Just make sure that it is at least one inch higher than the thing that you want to protect from lightning.

A grounding plate is a good idea for your boat if you plan on anchoring close to shore. It prevents internal side strikes from the electrical currents flowing through your boat. Additionally, it reduces emi, shock, and tremors. However, there are still certain areas that are particularly vulnerable to lightning strikes. Therefore, it is vital to consider your safety when docking in these areas.

Radio antennas

If your boat has an onboard VHF antenna, then you should consider installing a radio antenna for lightning safety. While most antennas are not lightning-protected, they can be mounted on a mast or a tower. The antenna itself can be installed in such a way that it looks like a traditional antenna. However, make sure that the antenna is installed high enough to create a cone-shaped zone of protection.

The top portion of the mast will act as the air terminal. Grounding conductors will then connect to it and dissipate the current into the water. In most cases, the antenna mast is connected to the downconductor network. To prevent this kind of incident, make sure that the copper strips on the mast and on the downconductors are at least eight AWG. Make sure that the wiring between the radio antenna and the transducer is insulated against moisture and is grounded to a ground plate.

If you’re on a boat that is in the ocean, you may need to install a radio antenna. The electrical charge from a lightning strike is 1,000 times greater than the saltwater voltage. An ungrounded antenna, on the other hand, cannot conduct electricity into the water. The person on the radio is directly in contact with a piece of metal that extends through the boat’s hull. The person on the radio is therefore the best conductor of an electrical charge.

Through-hull fittings

Through-hull fittings can be a critical component of a boat’s lightning protection system. Proper installation will reduce the chance of a strike on a boat, as lightning prefers to travel on the surface of water. A lightning safety system should have multiple grounding electrodes located around the boat. Lightning prefers to travel along the surface of the water, so supplemental grounding electrodes will encourage this path.

Through-hull fittings should be at least six inches high above anything nearby. The primary conductor should be at least four-inch thick and project over everything in the 90-degree cone-shaped zone, which is measured from the top of the fitting to its bottom. This 90-degree “cone of protection” should fully enclose the boat and provide relative safety. However, there are no guarantees, and lightning is unpredictable. Nevertheless, proper lightning protection is essential to ensure a safe boating life in areas prone to strikes.

For a more reliable solution, use stainless steel through-hull fittings. They should be marine-grade (AISI 316) and should have nonmetallic seacocks. Plastic seacocks are also an option, but they tend to rust, and rarely fail unless exposed to an unavoidable external force. But the downside of stainless steel through-hull fittings is that they are expensive.

Diving deep during a lightning storm

As lightning travels at a faster rate than sound, it’s critical to avoid diving in thunderstorms. When you hear thunder, head for shore immediately. A dive boat fitted with a lightning conductor can direct the electrical charge into the water, ensuring that you stay away from the most vulnerable areas. You should also avoid using electronic equipment in an exposed area. Before diving, consult a qualified diver and observe the weather forecast. If the conditions look bad, postpone your trip or seek shelter on shore.

A boat’s hull is also very vulnerable to damage from a lightning strike. While it can be tempting to dive deep during a storm, it’s not a safe choice. In addition to being uncomfortable and crowded, a boat’s hull makes it susceptible to damage and the potential for a lightning strike. As a result, boat owners typically place divers in the water for longer periods to minimize the risk.

Precautions to take after a lightning strike

If you have been in a boat that was struck by lightning, there are several precautions that you must take. The first one is to avoid standing near tall objects. If possible, try to stay in the middle of the boat, preferably a low lying area. If you are not in the boat at the time, stay in an enclosed building or vehicle. After you’ve secured yourself, look for a hole where the lightning exited the vessel and seek shelter there


After a lightning strike, you must act immediately to save your life. You should check for a heartbeat and breathing. If you see one, start cardiopulmonary resuscitation (CPR) immediately. If you are not sure how to do this, make sure you know how to perform it. If you are unsure of how to do this, follow a few basic guidelines. Regardless of whether you are on a sailboat or a power boat, you must know how to perform CPR.