Suunto HELO2 manual Emergency ascents, Dive computer limitations, Mixed gas diving

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YOU ARE ADVISED TO MAKE A

DEEPSTOP AT 18 M. THE SECOND

INDICATOR SHOWS THAT YOU HAVE 110

SECONDS LEFT OF YOUR DEEPSTOP.

In order to optimize the response to different increased risk situations, an additional category of stop, referred to as a Mandatory Safety Stop, has been introduced. The combination of stop types depends on the user settings and the specific dive situation.

To get the most from the RGBM safety benefits, refer to Section 10.2. RGBM.

5.3. Emergency ascents

Before you dive, you must have the dive plan created with the Suunto Dive Planner printed out on a slate. You must also have a back-up plan for lost gases. In the unlikely event that the dive computer malfunctions during a dive, start using an alternative depth gauge and timer and following the ascent schedule and gas switches that are on the slate. If you dive using only air, follow these steps:

1.Assess the situation calmly and then move promptly to less than 18 m/60 ft.

2.At 18 m/60 ft, slow down your ascent rate to 10 m/33 ft per minute and move to a depth between 3 and 6 m/10 and 20 ft.

3.Stay there for as long as your gas supply will safely allow. After reaching the surface, do not dive for at least 24 hours.

In the event that the dive computer functions but a required gas is not available, you can use your diving partner's gas, which is set as a secondary gas on the dive computer. Displayed ASC TIME is not correct, but the decompressions are calculated correctly.

In the event that a required gas is not available at all, decompress for as long as you can by using the next most suitable gas that has the highest oxygen content. Notice that the oxygen content should be low enough to not violate the maximum partial pressure of oxygen (PO2).

5.4. Dive computer limitations

While the dive computer's calculations are based on current decompression research and technology, it is important to realize that the computer cannot monitor the actual physiological functions of an individual diver. All decompression schedules currently known to the authors, including the U.S. Navy Tables, are based on theoretical mathematical models, which are intended to serve as a guide to reduce the probability of decompression illness.

5.5. Mixed gas diving

Diving with gas mixes provides you with an opportunity to increase bottom times, shorten decompression times, decrease the oxygen partial pressure at depth, and reduce the risk of nitrogen narcosis or decompression illness by reducing the nitrogen content in the gas mix.

However, when the gas mix is altered or depth increased, the oxygen partial pressure is generally increased. This increase exposes the diver to an oxygen toxicity risk not usually considered in recreational diving. In order to manage this risk, the dive computer tracks the time and intensity of the oxygen exposure and provides the diver with information to adjust the dive plan in order to maintain oxygen exposure within reasonably safe limits.

In addition to the physiological effects of enriched air on the body, there are operational considerations to be addressed when handling altered breathing mixes. Elevated concen- trations of oxygen present a fire or explosion hazard. Consult the manufacturer of your equipment to check its compatibility with nitrox.

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Contents HelO2 Page Welcome to the World of Suunto Diving Instruments Care and Maintenance of MY Suunto Diving Computer Using HelO2 with Dive Manager and Dive Planner Welcome to the World of Suunto Diving InstrumentsPhysician regarding your fitness before diving Or professional diving activitiesOr death USE BACK-UP INSTRUMENTS! Make sure that you use back-up ASC Time symbol and the upward pointing arrowStop, and Rgbm adjustments are correct Diving with the dive computerBatteries. Recycle or dispose of used batteries properly Before the instrument has counted down the no-fly timeSuunto HELO2 AT a Glance Button symbols and functionsSymbol Button Press Main functions Navigating in the menusDown Long Enter Setting mode Setting the date Time mode settingsSetting the time Setting the unitsAC water contacts Setting the backlightSetting the tones Suunto Technical Rgbm Before DivingPlanning your dives Mixed gas diving Emergency ascentsDive computer limitations Audible and visual alarms Alarm indication Alarm reasonOut of calculation limits Alarm indicationError conditions Gas mixPairing and code selection Wireless transmissionInstalling the wireless transmitter Omitted decompressionTransmitting data Display IndicationDive Mixed GAS Dive mode settingsSetting the gases Setting the personal/altitude adjustments Setting the depth alarmSetting the dive-time alarm Before you have ascended above this depthSetting the tank pressure Setting the sample rateSetting the tank pressure alarm Setting the HP codeActivation and pre-checks Accessing Dive modeDive mode activation Diving at altitude Battery power indicationAlt. adjustment value Altitude range How the Altitude value is set Personal adjustmentsPersonal adjust- Condition Desired tables Ment value Before divingMandatory Safety Stops Safety StopsRecommended Safety Stops Other personal injury, and deathDeep stops Basic dive data DivingDiving-related information Decompression dives Ascent rate indicatorBookmark Ceiling, ceiling zone, floor and decompression range Than at the ceilingDisplay above the floor Accident, you should stay somewhat below the ceilingDisplay below the floor Display at the ceiling zoneDefault gas mix settings Diving in Mixed GAS modeBefore diving in Mixed GAS mode Oxygen and helium displaysOxygen limit fraction OLF Gas change and multiple breathing gas mixesDiving in Gauge mode Surface interval Alarms Symbol on displayAfter Diving Dive numberingRepetitive dive planning Plan modeDive Planning mode PLANnodec Flying after divingMixed GAS mode, it does not affect the calculations PLANNoDec modeMemory mode Dive numbering shown during dive planningDive logbook MEMLogbook Dive history Suunto Dive Planner SDPDive Planner. It ensures that you have a valid decompression Suunto Dive Manager SDMPage Care and Maintenance of MY Suunto Diving Computer Water Contacts and Push ButtonsWarranty FAQsBattery replacement and strap kits must be used Replacing the battery Battery ReplacementBattery kit Required toolsMade in a proper manner to avoid any leakage of water into Battery compartment lid, indicating a leakWireless transmitter battery replacement TransmitterTransmitter battery kit Stalling the transmitter batteryPage Technical Data Battery RgbmAfter dive planning Diver safety and Suunto Technical Rgbm modelSuunto Technical Rgbm decompression model Altitude diving Oxygen exposurePatent notice Intellectual PropertyCopyright Trademark 12.2. CE DisclaimersUser’s responsibility Warranty Period Exclusions and LimitationsLimitation of Liability Access to Suunto warranty serviceOther important notices Page Disposal of the Device Glossary EAD EANNo DEC Time Customer Service Contacts CopyrightPage TWO Year Warranty Page Page Suunto Oy 4/2009