Suunto D4 manual Altitude diving, Oxygen exposure

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10.2.3. Altitude diving

The atmospheric pressure is lower at high altitudes than at sea level. After traveling to a higher altitude, you will have additional nitrogen in your body, compared to the equilibrium situation at the original altitude. This "additional" nitrogen is released gradually over time and equilibrium is restored. It is recommended that you acclimatize to a new altitude by waiting at least three hours before making a dive.

Before high-altitude diving, the instrument must be set to the Altitude Adjustment mode to adjust the calculations for the new altitude. The maximum partial pressures of nitro- gen allowed by the mathematical model of the dive computer are reduced according to the lower ambient pressure.

As a result, the allowed no-decompression-stop limits are considerably reduced.

10.3. Oxygen exposure

The oxygen exposure calculations are based on currently accepted exposure time limit tables and principles. In addition to this, the dive computer uses several methods to conservatively estimate the oxygen exposure. For example:

the displayed oxygen exposure calculations are raised to the next higher percentage value

for recreational scuba diving, the recommended upper limit of 1.4 bar PO2 is used as a default

the CNS % limits up to 1.6 bar are based on 1991 NOAA Diving Manual limits

the OTU monitoring is based on the long-term daily tolerance level and the recovery rate is reduced

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Contents Page Getting Started with Your Suunto D4 Diving Care and Maintenance of MY Suunto Diving Computer Intellectual Property Welcome to the World of Suunto Diving INSTRU- Ments Page Any confusion resulting from neglecting to follow this users Page Selected O2% and a Maximum PO2 of 1.4 BAR Have not Personally Verified ITS Contents Dive Computer will not Accept Fractional Page Suunto D4 AT a Glance Navigating in the menusButton symbols and functions Symbol Button Press Main functions ModeDown Long Enter Setting mode Time mode settings Getting Started with Your Suunto D4Setting the alarm More than 5 secondsSetting the time Setting the dual timeSetting the date Setting the unitsSetting the backlight Setting the tonesStopwatch AC water contactsPage Before Diving Suunto RGBM/Deep Stop Algorithm Emergency ascentsDive computer limitations NitroxAudible and visual alarms Free divingAlarm type Alarm reason Oxygen alarms in Nitrox mode Alarm typeError conditions Omitted decompressionDive mode settings Setting RgbmSetting the depth alarm Setting the depth notify alarm Free mode Setting the dive-time alarmSetting the nitrox values Setting the personal/altitude adjustmentsSetting the surface time notify alarm Free mode Setting the sample rateSetting the Deep Stops Setting the Rgbm valuesActivation and pre-checks Accessing Dive mode Dive mode activationPage Battery power indication Diving at altitudeAlt. adjustment value Altitude range How the Altitude value is setPersonal adjustments Personal ad Condition Desired tables Rgbm setting Desired Tables Effect Safety StopsRecommended Safety Stops Mandatory Safety Stops To or below Ceiling Deep stops Diving in AIR mode DIVEair DivingBasic dive data Down Button Toggles Between Maximum Depth and Current Time Ascent rate indicator BookmarkDecompression dives Ceiling, ceiling zone, floor and decompression range Page Display below the floor Display above the floorDisplay at the ceiling zone Display above the ceilingDiving in Nitrox mode DIVEnitrox Before diving in Nitrox modeDefault nitrox settings Oxygen displaysDown Button Diving in Free mode DIVEfree Oxygen limit fraction OLFThere is no ascent rate monitoring in the Free mode Day HistoryNew one Free dive time limit Alarms Symbol on display After DivingSurface interval Dive numbering AIR and Nitrox Free Dive Repetitive dive planningFlying after diving Memory mode Dive Planning mode MEMPlan See .7. Error conditions Dive numbering shown during dive planning Dive logbook MEMLogbookBeen replaced according to the instructions Dive history MEMHistory Scuba HistoryFree Dive History Suunto Dive Manager SDM Page Page Care and Maintenance of MY Suunto Diving COM- Puter Water Contacts and Push ButtonsMaintenance FAQs Water Resistance InspectionWhat are Original Suunto ACCESSORIES? Page Battery Replacement By the warrantyDepth gauge Technical DataTemperature display Calendar clockDisplays only in Nitrox mode Logbook/dive profile memoryOperating conditions Tissue calculation model BatteryRgbm Diver Attention Symbol Advice to Extend Surface Interval Suunto Rgbm adaptive decompressionNo-decompression limits No-decompression time limits for various depths m No-decompression time limits for various depths ft Altitude diving Oxygen exposurePage Intellectual Property Copyright TrademarkPatent notice Disclaimers User’s responsibility12.2. CE Page Warranty Period Exclusions and LimitationsAccess to Suunto warranty service Page Other important notices Limitation of Liability Disposal of the Device Glossary DAN DCI103 104 105 Customer Service Contacts Suunto Oy 10/2007