Shark Shield FAQ

Shark Shield
Frequently Asked Questions

How does the Shark Shield effectively deter sharks?
Can SeaChange Technology guarantee the Shark Shield works?
When should I turn on the Shark Shield?
Do I have to leave the Shark Shield switched on all the time?
Does the Shark Shield attract sharks?
If I am wearing a unit, but my buddy/mate is not, is he/she more prone to attack?
Who can use the Shark Shield?
Can the unit be used by children?
On which part of the body is the Shark Shield worn?
Do the electrodes need to be immersed in the water for a protective field to be created?
Does the Shark Shield repel any other creatures?
Has the Shark Shield been proven to be safe to humans?
Will I get an electric shock?
Does the Shark Shield harm sharks?
How long does the battery pack last?
How do I know when the battery pack is getting low?
Can I “top up” the NiMH battery pack when it still has some charge left in it, or does it need to be fully drained?
How should I store the battery pack?
How can I test that the unit is working properly?
What is the warranty period for the Shark Shield unit?
Can I use the Shark Shield in estuarine environments?
What sort of testing has been done on the unit?
What is the depth rating of the Shark Shield?
Does the field of the Shark Shield interfere with a divers hoseless air integrated dive computer?

How does the Shark Shield effectively deter sharks?
The Shark Shield produces a unique conductive field that surrounds the wearer. Sharks are sensitive to this field and when they approach too close, the field causes muscular spasms that result in the shark leaving the area.
It is believed the field is detected by the shark through its sensory receptors, known as the Ampullae of Lorenzini, found on the snouts of all predator sharks. Once detected by the shark's sensors, the field causes extreme discomfort and muscle spasms, resulting in the animal fleeing the area.
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Can SeaChange Technology guarantee the Shark Shield works?
Certainly it works.
Apart from the unsolicited testimonials from users stating how their lives have been saved by this technology, we have years of conclusive scientific testing. It is important to note that all our testing is conducted in extreme circumstances in a bloodied and baited environment.

However, it must be remembered that all sharks are dangerous and unpredictable creatures, and therefore a 100% guarantee cannot be given. It is impossible to guarantee that all sharks will be deterred under all circumstances.

Since the inception of airbags in motor vehicles many lives have been saved by the invention, but it cannot be claimed that they save lives 100% of the time.

With or without the protection of a Shark Shield, all sharks should be treated with respect and caution. Water sport participation in the presence of sharks is inherently dangerous. Any human activity in the water near sharks must always be considered as possessing a considerable degree of risk.

Like any piece of electronic equipment, the Shark Shield will not work effectively if not used in the correct manner, and if the units are not maintained correctly. The product instruction booklet provided with the unit must be read thoroughly prior to using the Shark Shield.

In April 2003, following the inquest into the death of a commercial scallop diver in South Australia, the State Coroner recommended that "...all divers diving in waters where there is the risk of the presence of sharks should wear a shark repellent device such as a Shark Shield or Shark POD..."
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When should I turn on the Shark Shield?
Do not turn the unit on until you enter the water.
Turn the unit off when exiting the water.
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Do I have to leave the Shark Shield switched on all the time?
Yes, when in the water. According to the International Shark Attack File of the Ichthyology Department of the Florida Museum of Natural History - see www.flmnh.ufl.edu/fish/sharks - 52.3% of shark attack victims did not see the shark prior to contact, therefore do not wait to turn the unit on. Ensure the unit is turned off when you are exiting the water.
However, the unit must be switched off when inside a shark cage or in any other confined areas such as wrecks or caves.

Also see "When should I turn on the Shark Shield."
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Does the Shark Shield attract sharks?
No! Surprisingly, this is a question SeaChange is sometimes asked, due to some common misconceptions being quoted. Shark Shield does not "attract" sharks - it deters them. An explanation follows.
All free swimming sharks rely on various highly developed senses to detect and track their prey. In order of distance, the senses triggered are smell, sound, sight and at very close distances only, electrical impulses.

Smell - a long range sense

Sharks will follow a scent trail over considerable distances. Blood, body fluids and secretions from shell fish may deposit a trail several kilometres from the source.

Sound - a long range sense

Low frequency vibrations travel hundreds of metres through the water and are known to attract sharks. Typical sounds might be struggling fish or humans swimming.

Sight - a long range sense

Most of the sharks that pose a threat to us have excellent eyesight and can readily track prey by sight, even in low light.

Electrical impulses - used at very close range only

A particularly unique sense used by sharks at close quarters, consists of hundreds of tiny gel filled pores around the snout. These are known as Ampullae of Lorenzini and are used to pick up the electrical signals emitted by the nerve impulses from living creatures. When a shark closes in for an attack, a protective membrane pulls back over its eyes rendering it temporarily blind. For the few seconds this may take, the shark is able to track it's prey by the utilisation of its Ampullae of Lorenzini.

Following the laws of Physics, the electrical signal from the Shark Shield decays rapidly in the water. A shark is therefore only attracted to the source by it's long distance senses, being scent and sound - not by the Shark Shield.

When a shark is in an investigtive mode, the electrical field from the Shark Shield presents an unfamiliar and unpleasant pulsing sensation. The unique wave form emitted from the Shark Shield is designed to overload the shark's central nervous system and inflict discomfort as it approaches at close range in its investigative mode.

The electrical field generated by the Shark Shield does not replicate that given off by a fish or seal and hence it is not recognised by a shark, as a desirable or attractive stimulus.

The testing programmes we conduct are extremely expensive to operate and as such it is vitally important to maximise shark visitation to the site. Over many years of field testing the original Shark POD, and later the Shark Shield, we have always had to stimulate the sharks long distance senses by using blood and offal to attract the sharks and carry out testing, because the Shark Shield field does not attract them.

The testing programmes, and subsequent reports from users of this technology, proves the Shark Shield deters sharks - it clearly does not attract them.
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If I am wearing a unit, but my buddy/mate is not, is he/she more prone to attack?
Anyone not wearing a Shark Shield is at more risk of being attacked than somebody who is wearing a unit.
However the fact that one person is wearing a unit does not mean that those around him/her are placed at greater risk than if nobody in the group was wearing a unit. THE UNIT DOES NOT ATTRACT SHARKS.
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Who can use the Shark Shield?
Scuba Divers - the Scuba, Freedom 2 or Freedom 4 units
Surface Air Supply Divers - the Mariner unit
Surfers - the Freedom 2 or Freedom 4 units with leg rope accessory
Snorkellers - the Freedom 2 or Freedom 4 units
Swimmers - the Freedom 2 or Freedom 4 units
Spearfishermen - the Freedom 2 or Freedom 4 units

Mariner - can be used by anyone engaged in marine activities on the ocean. It can be deployed over the side of a boat, attached to abuoy or surface air supply line, or used on fishing nets to create a shark exclusion zone to save the catch and prevent shark bycatch.

Please note: if using the Scuba or Mariner unit (for diving) a wetsuit needs to be worn to reduce the skin stimulation effect.
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Can the unit be used by children?
The Shark Shield must not be used by children under the age of twelve years old. The Shark Shield is a safety device, not a toy. It is deemed that children under the age of twelve, even with adult supervision, do not have the necessary level of maturity required to use such an electrical device, which, if not used correctly, will not give the level of protection to the user that it is designed to do.
Children above the age of 12 must be supervised by an adult to ensure that the Shark Shield is used correctly and in accordance with the instructions and warnings contained in the Instruction booklet supplied with each unit.
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On which part of the body is the Shark Shield worn?
Scuba (DIVE01) - the main housing of the unit can be worn on the thigh (a strap is provided), in a BC pocket, or attached to the front of the BC via a BC strap or D ring. The antenna electrode is worn on the ankle, with the antenna protruding out the front, so that it rests on the fin. The pad electrode is secured to the back of the scuba cylinder via the BC securing strap.
Freedom 2 (GPSS01) or Freedom 4 (GPSS02) - worn on the ankle. Both electrodes are encased in the antenna.

Mariner (BOAT01) - worn on a divers air line, attached to a surface marker buoy, a rope or decompression bar.
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Do the electrodes need to be immersed in the water for a protective field to be created?
Yes, most definitely. Both electrodes need to be immersed in the water for a protective field to be created. In the case of the Freedom and Mariner units, both electrodes are encased in the antenna.
In the Scuba unit one electrode is encased in the antenna protruding from the ankle, whilst the other electrode is worn on the scuba cylinder.
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Does the Shark Shield repel any other creatures?
One of the distinct advantages of this unique electronic wave-form is that it only repels predator sharks.
It does not repel any other form of marine life.
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Has the Shark Shield been proven to be safe to humans?
The field generated by the Shark Shield, when used in accordance with the instructions contained in the instruction booklet supplied with each unit, poses no danger to the user, to sharks or to the environment. The field can be detected if the electrodes come into very close contact with the skin.
Direct contact with, or very close proximity to the antenna, may cause twitching of the surface muscles of the skin, in time with the slow pulsing of the signal. The conductive field readily travels through seawater, it being a better conductor than the human body thus the field tends to surround the body rather than penetrate it. Scientific tests show that the type of signal generated by the shark shield is unable to pass through body tissues, unlike radio waves or microwaves that readily penetrate the body, and therefore it poses no health problems for users.

However, anyone with any health condition which could increase their sensitivity to the fields created by the Shark Shield should not use the device. Such conditions include heart disease, a history of heart attack, peripheral vascular disease, stroke, a history of fainting or epilepsy, lung disease, or if the user is on any prescription drugs that are administered for these conditions. People who have pacemakers or are pregnant must not use the Shark Shield and should also avoid swimming near any other person using the Shark Shield.
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Will I get an electric shock?
Placing the hand near the electrodes will cause stimulation of the surface muscles of the skin. It is imperative that you never touch the electrodes when the unit is switched on, as this will result in extreme discomfort.
If using the Scuba or Mariner units (for diving), these must be worn with a wetsuit to avoid skin stimulation.
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Does the Shark Shield harm sharks?
From the tests conducted to date, the Shark Shield does not harm the shark. The majority of initial testing was carried out by a team of marine biologists at the Natal Sharks Board of South Africa.
Scientific tests, as well as observations, show the field emitted by the Shark Shield causes discomfort to the shark, which can eventually lead to muscular spasms. However once the shark leaves the area, there is no lasting detrimental effect to the shark.
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How long does the battery pack last?
The battery pack supplied with the Scuba, Freedom 4 and Mariner units will last 4 hours if fully charged prior to use.
The battery pack supplied with the Freedom 2 unit will last 2 hours if fully charged prior to use.
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How do I know when the battery pack is getting low?
A green pulsing LED shows when the unit is operating normally.
If the battery pack is running low a continuous red LED lights up next to the green pulsing LED. This warns the user that they have 15 minutes left in which to leave the water before the battery is fully discharged.
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Can I “top up” the NiMH battery pack when it still has some charge left in it, or does it need to be fully drained?
Yes.
Topping up the battery pack when partially charged will not damage the battery or lead to memory effect problems. However, any rechargeable battery benefits from being totally discharged every 6 months.
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How should I store the battery pack?
The battery pack should be stored fully charged.

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How can I test that the unit is working properly?
Holding either hand close to the antenna, i.e. less than 300mm (12 inches) away, whilst immersed in water and while the unit is switched on, is a handy way of checking the field. If the unit is functioning properly, the user should feel a distinct pulsing of the skin muscles of the hand. For surfers, being on the surface of the water and often in bright sunlight, this is the easiest way to check the units operation.
Divers on the other hand will usually be in more subdued lighting where the LED status indicators may be more easily seen.
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What is the warranty period for the Shark Shield unit?
The Shark Shield has a 12 month manufacturers warranty, provided the unit is maintained as per the instructions set out in the Product Information Booklet supplied with the product. The battery pack supplied with the product, or sold as an accessory, comes with a 6 month warranty from the date of purchase.
As outlined in the Product Information Booklet, the warranty is only valid if the Manufacturers Warranty Certificate has been completed and returned. It is also a requirement that proof of purchase be supplied when making a warranty claim.
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Can I use the Shark Shield in estuarine environments?
The Shark Shield is designed for use in seawater only.
The Shark Shield cannot be used in fresh or estuarine waters, as it will not establish a protective field in freshwater due to the water's reduced ability to conduct electrical energy.
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What sort of testing has been done on the unit?
The electronic wave-form used in the Shark Shield has been on the market since 1995, in the guise of the Shark POD, and has proved its effectiveness in the field time and time again.
The Shark Shield has been thoroughly tested in the laboratory, and on site with Great Whites, both in Cape Town, South Africa and Neptune Island, South Australia.

Field testing of the Shark Shield on predator sharks involves attracting sharks using blood and offal. The unit is turned on and placed into the water with fish bait attached to attract the shark. The shark's behaviour is then observed and recorded as it investigates the food source. The testing conducted to date proves conclusively that sharks detest the effect the field has on them and will keep a safe distance between themselves and the Shark Shield.

Remember: This testing is conducted under the worst possible scenario. The shark is stimulated, hungry and excited. A situation that any responsible person will avoid at all costs.
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What is the depth rating of the Shark Shield?
100 Metres.

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Does the field of the Shark Shield interfere with a divers hoseless air integrated dive computer?
From the tests conducted to date, no interference has occurred on the Uwatec range of computers. However the Shark Shield field has on some occasions (but not usually) interfered with the Suunto Vytec if wearing the Scuba unit, but not if wearing a Freedom unit.

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Shark Shield FAQ

Shark Shield Frequently Asked Questions

Shark Shield
Frequently Asked Questions