Technical Notes

Immersion Alarm and Salt Water

Natural fresh water does not greatly impede the signal radiating from an immersed Turtle. No matter how fast a Turtle descends in the water, it will always alarm on the way down.

An increase in salt concentration increases water’s conductivity, making propagation of a radio wave more difficult. This has the effect of reducing “depth coverage”, the depth below which a Base Station cannot decipher the signal transmitted by an immersed Turtle.

Note: Salt does NOT affect the operation of the electronics or a Turtle’s operating life.

Child Use with Natural Fresh Water

The following applies to fresh water having NO sea water influence.

The Turtle may be attached anywhere a child cannot remove it, except under clothing that might prevent or delay it getting wet on entry in the water.

Use with Sea Water

The Turtle will not alarm reliably on entry in the water. To work reliably, the Turtle must thereafter break or nearly break the surface of the water.

Boating – Alarming is not 100 % reliable unless the subject is also wearing a life jacket.

Attach Turtle to rear shoulder strap [above the buoyancy line] using Velcro Adaptor, or to wrist using locking wristband.

Shoreline – While not 100% reliable in all cases, Safety Turtle is effective with a graduated beach. Even if the child is knocked down by a breaker, alarming will occur when the breaker recedes.

Attach Turtle to wrist only.

Use with Salt Chlorinated Pools

Do you have a salt chlorinated pool? If you aren’t sure, consult your pool contractor. If you do have a salt chlorinated pool, read the following:

The salt concentration of chloride salt pools and spas is typically 2,400 to 3,600 ppm, but this varies in practice. The concentration of bromide salt pools and spas is about half this. The salt concentration of non-salt chlorinated pools and spas, including pools using ozonators, varies from 50 parts per million [ppm] to several hundred ppm.

For succesful set up with a chloride salt pool, the Base Station may have to be less than 50 ft. [15 m.] from the pool. Above a 4000 ppm salt concentration, the Base Station may have to be pool side. Consider a Commercial/Extended Range System that alarms at both the pool and in the residence.