BSAC Ocean Diver Test Questions with 100% Complete Solutions Rated A+

Diving from live aboard boat - Correct Solution Booked for one week or longer - advantages - function as dive platforms and floating hotels - have large cruising range with often knowledgable crew - bigger boats have good deck and kittign up space - have compressor and provide cylinders and nitrox Disadvantages - cost, returning to shore may not be option, generally spare diving kit no readily available, need to get on with all divers on board Reef diving - Correct Solution Havens for marine life Risks = risk going over planned depth or time - some marine life hazardous - reefs can result in wave action and currents Precautions - don't touch marien creatures, plan the dive dive the plan Marine conservation - Correct Solution Good buoyancy control important - careful finning also important - don't touch marine life - Wreck diving - Correct Solution Can become man-made reefs - represent period of history - can become festooned with nets - often large sections of overhanging metal - avoid accidentally swimming into wreck - wreck penetration is dangerous and requires specialised training - pieces of wreckage may fall - metal cancause cuts - rust can reudce viz - some wrecks can contain live munitions Precautions - take knife or line cutter - maintain control of buoyancy - avoid crawling along bottom and kicking up silt -Do not take anything - wrecks are war graves, treat with respect - any item taken from wreck should be declared to the Reciever of Wreck Night diving - Correct Solution Diving at night = see different marine creatures - use a torch focuses divers attention on what see within torch beam Risks = risk of separation increased, also easier to become disorientated Precautions - torch required by each diver for illuminsation and backup light should be carried in case of failure of maine torch - if backup torch has to be used abort dive and surface - in dark necessary to shine torch on hand to illuminate signals - avoid shining torch directly at buddy A clamp - Correct Solution Makes use of an O ring set into the valve outlet 232 bar pressure DIN - Correct Solution No o ring Fitted to cylinders up to 300 bar Can add on a clamp equipment to allow use of regulators equipped with A-clamp attachment Not all DIN support all pressure types M26 - Correct Solution USed above 22% oxygen BCD components - Correct Solution Integrated gas bladder filled by direct feed which connects via an Intermediate pressure hose to the regulator - push button to inflate BC Oral inflation mouth piece Over inflation pressure relief valves Also has manually operated dump mechanism -Washed inside and out with fresh water - disinfecting solutions should be used inside BCD - should be dry and stored slightly inflated - do not breathe from BC Regulators - Correct Solution Deliver air at ambient pressure - first stage reduces pressure in cylinder to intermediate pressure around 10 bar above ambient - gas passed down interstage, intermediate pressure hose to regulator second stage-second stage reduces pressure further to ambient pressure - exhaled air expelled via exhaust valve - contain a octopus for your buddy/you -Alternative source is additional second stage regulator connected to first stage - back up system for diver or buddy - usually marked yellow and stamped with A -Contents gauge connected via hose to first stage - has to be high pressure hose as it delivers high pressure gas for gauge to read -Many designed for use in temperatures above 10 degrees - regulators with Nitrox should be in Oxygen service Regulator care - Correct Solution Wash while pressurized and connected to cylinder, do not press purge button while washing with fresh water -dry before storing Serviced once a year Weights - Correct Solution Usually on belt with quick release buckle - or can be in harness - some BCs had integrated weight pockets - require mechanism for easy jettisoning - but important weight not lost unintentionally - release mechanisms can be buckle, velcro or release clips -Washed in fresh water and allowed to dry before storage What must never be done - Correct Solution Holding breath - as pressure decreases on ascent air in lungs at ambient pressure would increase in volume, causing damage Buoyancy - Correct Solution Neutral = In equilibrium with surrounding water - weightless state - need adjustment throughout, reduces physical effort Positive = when diver is too light, positive buoyancy and ensuing struggle to remain below water is physically tiring - being too light risks the possible over expansion of lungs Negative = too heavy - tiring - damage marine life and equipment - risk descending below safe depths Buoyancy in practice - Correct Solution Input air into BC while descending as air compresses reducing buoyancy - remove gas while ascending to equalise buoyancy - Body temperature control - Correct Solution Core body temperature - consists of main body arease g. . brain, chest organs and abdomen - surrounded by peripheral limbs skin and muscles - peripheral subject to greater variation - heat loss due to cool environment can cause reduced blood supply to periphery - can feel numb - muscles contract i.e. shiver - can lead to hypothermia -Water conducts heat 25 times faster than air - need to insulate - more than 21 okay with minimal insulation - between 20 and 10 degrees wet or semi drysuit required at minimum - below 10 drysuit strongly recommended