Suunto EON Steel Black User Guide 3.0
Alarms, warnings, and notifications
Suunto EON Steel Black has color-coded alarms, warnings and notifications. They are shown prominently on the display with an audible alarm (if tones are on). Alarms are always red. Warnings may be red or yellow. Notifications are always yellow.
When an alarm, warning, or notification occurs, a message is displayed as a pop-up. Pop-up messages can be acknowledged by pressing any button. The information needing attention remains on screen or as a scrollable element in the bottom field until the situation is back to normal.
Alarms are critical events that always require immediate action. When an alarm situation comes back to normal, the alarm will stop automatically.
| Alarm | Explanation |
|---|---|
 | Ascent speed exceeds safe speed of 10 m (33 ft) per minute for five seconds or more. |
 | Decompression ceiling or mandatory safety stop is broken by more than 0.6 m (2 ft) on a decompression dive. Immediately descend back below ceiling depth and continue to ascend normally. |
 | Partial pressure of oxygen exceeds safe level (>1.6). Immediately ascend or change to a gas with lower oxygen percentage. |
 | Partial pressure of oxygen below safe level (<0.18). Immediately descend or change to a gas with higher oxygen percentage. |
Warnings alert you to events that can impact your health and safety if you do not take action. Acknowledge the warning by pressing any button.
| Warning | Explanation |
|---|---|
| CNS 100% | Central Nervous System (CNS) Oxygen Toxicity level at 100% limit |
| OTU 300 | Recommended daily limit for Oxygen Tolerance Unit/Oxygen Toxicity Unit (OTU) reached |
| Depth | Depth exceeds your depth alarm limit |
| Dive time | Dive time exceeds your dive time alarm limit |
| Diluent high pO₂ | Diluent partial pressure of oxygen exceeds safe level (>1.6); no immediate danger unless diluent is used, e.g. diluent flush |
| Diluent low pO₂ | Diluent partial pressure of oxygen below safe level (<0.18); no immediate danger unless diluent is used, e.g. diluent flush |
| Gas time | Gas time is below the gas time alarm limit you set, or tank pressure is below 35 bar (~510 psi), in which case gas time is zero. |
| Safety stop broken | Ceiling of the voluntary safety stop broken by more than 0.6 m (2 ft) |
Tank pressure | Tank pressure is below your tank pressure alarm limit. There is a built in 50-bar alarm that cannot be changed. In addition to it there is a configurable tank pressure alarm, you can set to any value between 10-360 bar (145-5221 psi) and your dive computer also shows an alarm when that value and 50 bar (725 psi) pressures are reached. The tank pressure number is forced onto the display and turns yellow after the value you set and red after 50 bar (725 psi). |
Notifications indicate events that require preventive actions. Acknowledge the notification by pressing any button.
| Notification | Explanation |
|---|---|
| CNS 80% | Central Nervous System (CNS) Oxygen Toxicity level at 80% limit |
| OTU 250 | Approximately 80% of recommended daily limit for Oxygen Tolerance Unit/Oxygen Toxicity Unit (OTU) reached |
| Change gas | On multi-gas dive when ascending, it is safe to switch to next available gas for optimum decompression profile |
| Battery low | Approximately three hours of dive time left |
| Recharge needed | Approximately two hours of battery time left; re-charging required before next dive |
| Setpoint switched | Setpoint switched automatically or manually on a rebreather dive. See Setpoints. |
| Custom setpoint | Setpoint switched to custom setpoint on a rebreather dive. |