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Suunto EON Core User Guide - 2.0

Safety stops and deepstops

Safety stops

A three (3) minute safety stop is always recommended for every dive over 10 meters (32.8 ft).

The time for a safety stop is calculated when you are between 2.4 and 6 m (7.9 and 19.7 ft). This is presented with up/down arrows on the left side of the stop depth value. The safety stop time is shown in minutes and seconds. The time may exceed three (3) minutes if you ascend too fast during dive. Safety stops can be set to 3 (three), 4 (four), or 5 (five) minutes.

SafetyStop noDeco Core

Deep stops

Deep stops activate only when you dive deeper than 20 m (65.6 ft). During ascend, deep stops activate when you are halfway up from your maximum depth. Deep stops are presented like safety stops. You are in the deep stop area when the deep stop depth has up/down arrows in front of it and deep stop time is running. The deep stop window is +/- 1.5 m (4.9 ft). Calculation starts at deep stop target depth plus 0.5 m (1.6 ft). Calculation ends - 3 m (- 9.8 ft) away from deep stop depth.

There can be more than one deep stop during ascend. For example, if you dive to 42 m (137.8 ft), the first deep stop is prompted at 21 m (68.9 ft) and the second is at 10.5 m (34.4 ft) The second deep stop is 2 minutes long.

In the following example the diver dives down to maximum 30.4 m (99.7 ft) and has a deep stop at 15.2 m (49.8 ft):

Deepstop dive Eon

Below 20.0 m (65.6 ft), deep stop gets activated. In this case, as the diver ascends, the deep stop is necessary at halway of the maximum depth, so at 15.2 m (49.8 ft).

If the deep stop depth is 15.2 m (49.8 ft), the calculation starts at 15.7 m (51.5 ft) and stops at 12.2 m (40.0 ft). The deep stop window is +/- 1.5 m (4.9 ft) and when the diver is within the deep stop window, it is indicated with two white arrows pointing at each other on the display.

When the diver ascends above the deep stop window ceiling - in this case above 14.2 m (46.5 ft) - a downward pointing yellow arrow signals that the depth is not optimal, it is recommended to descend. The deep stop target depth number also turns yellow.

If the diver keeps ascending, after 0.5 m (1.6 ft), a downward pointing red arrow and an alarm notifies the diver to descend immediately. The deep stop calculation keeps running for another 1.5 m (4.9 ft) up but stops after that. In the above example it stops at 12.2 m (40.0 ft).


For safety reasons, you cannot switch off deepstops if helium (trimix gas mixtures) is enabled for the dive mode in use.

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