Suunto is committed to achieving Level AA conformance for this website in conformance with the Web Content Accessibility Guidelines (WCAG) 2.0 and achieving compliance with other accessibility standards. Please contact Customer Service at USA +1 855 258 0900 (toll free), if you have any issues accessing information on this website.

Suunto Nautic S User Guide

Table of Content
Table of Content
  • Mandatory dive alarms

Mandatory dive alarms

The following table shows all the mandatory warnings you may see during a dive. You can find the reason for the alarm and the solution of the issue in the table.

If multiple alarms occur simultaneously, the error with the highest priority will be displayed. Acknowledge the first alarm by pressing any button and the next one will appear.

AlarmExplanationHow to resolve the alarm?
alarm ascent speedAscent speed exceeds safe speed of 10 m (33 ft) per minute for five seconds or more.Stay within the green ascent rate indicators. Monitor for symptoms of DCS. Use extra conservatism for future dives.
alarm ceiling brokenDecompression ceiling broken by more than 0.6 m (2 ft) on a decompression dive.Descend deeper than the displayed ceiling value.
alarm ppo2Partial pressure of oxygen exceeds the maximum level (>1.6).Immediately ascend or change to a gas with lower oxygen percentage.
ppo2 alarm setPartial pressure of oxygen exceeds the set level for the gas.Immediately ascend or change to a gas with lower oxygen percentage.
alarm cnsCentral Nervous System (CNS) Oxygen Toxicity level at 80% or 100% limit.Switch to a gas with a lower ppO2 or ascend shallower (within decompression ceiling).
alarm otu80% or 100% of recommended daily limit for OTU reached.Switch to a gas with a lower ppO2 or ascend shallower (within decompression ceiling).
alarm tank pressureTank pressure is below 50 bar (725 psi).Change gas to a higher tank pressure or ascend to safety stop depth and terminate dive.
alarm safety stop brokenNot inside the safety stop window.Stay within the safety stop window 3 m – 6 m.
alarm ndlNDL is less than 5 minutes.Ascend shallower to avoid mandatory decompression stops.
alarm ooamThe decompression ceiling is broken for more than 3 min and your decompression stop is missed.Descend to the ceiling depth indicated in the switch window.
ndl alarmYour NDL reaches 0 min, and decompression stops are mandatory.Perform decompression stops as directed and always stay deeper than the ceiling value.
alarm batteryBattery is low (<10%) or critical (<5%).Recharge the device.

Table of Content