A higher concentration of salt in your pool reduces the ability of the Turtle to communicate with the Base Station. The salt increases the pool's conductivity, thus increasing the power loss of a radio signal passing through a given height of water.

Therefore, for a salt chlorinated pool, the Base Station is best located pool side, at least 3 feet (1 meter) above the water surface. [AnExtended Range System is then required to accomplish alarming in the house.]

Depending on distance [and physical obstructions] between where the Turtle is immersed and the Base Station, beeping in test mode may stop (indicating the signal is lost) before the Turtle reaches the recommended test depth of 4-6 inches. If a child free falls into this pool, the Turtle may not have time to transmit before the signal is effectively blocked.

Reducing the distance [and physical obstruction] to the Base Station will increase the achievable Turtle test depth.

For maximum safety when using with pools, the Turtle wristband should be locked on your child's wrist, not attached to another part of his/her anatomy or clothing. In the eventuality the alarm is not triggered on the way down, buoyancy, weight distribution and involuntary arm movement will still result in alarming within 5 - 10 seconds.

Most salt-water chlorinator manufacturers recommend that salt concentration not exceed 3,600 ppm. Terrapin also recommends that your salt concentration be measured and kept within recommended limits.

The thing to remember is that sea water, unlike fresh water, is an electromagnetic shield. Only half an inch of sea water effectively blocks the signal from an activated Turtle. On initial entry, a Turtle may therefore sink too fast to initiate alarming.

With this in mind, to work reliably, the Turtle must break or nearly break the surface of the water after initial entry, i.e., while wet.

Consider the case of boating. If worn on a life vest a few inches above the water line, the system is 100 % reliable. If worn on the wrist of a non swimmer not wearing a life vest, alarming may be delayed, or not occur at all. But chances of a hand breaking the surface of sea water [more buoyant than fresh] after initial entry are high, even of a non swimmer, providing the subject is not weighed by shoes, etc.

Now consider a shoreline. The first concern is spatial coverage - the Base Station has the same coverage of a shoreline whether water is fresh or salt. However, with seawater, there is no depth coverage. So, as in the boating case, a wet Turtle needs to break the surface after initial entry to ensure alarming. At a beach, particularly with rollers, this is likely. For a child reaching down, e.g., with a bucket, it is almost certain. A fall into deep water from a height will not be detected if the line of site is obstructed, e.g., by a sea wall.

For reasons that should now be obvious, when using with sea water, Turtle must be worn either on the wrist or on life vest above the water buoyancy line. Safety Turtle has proven reliable with pets, providing Turtle is located on top side of collar.

Safety Turtle is not a substitute for supervision, barriers, and other measures, for children. It is only effective as a last layer of protection.