Supv Notes Flashcards
How many times does water conduct heat compared to air?
24 times
Water is a much better conductor of heat than air.
How many times does helium conduct heat compared to air?
6 times
Helium is a good conductor but not as effective as water.
In which medium does light travel faster, air or water?
Air
Light’s speed is affected by the medium it travels through.
How many times faster does sound travel in water compared to air?
4 times
Sound waves travel much faster in denser mediums like water.
How much nitrogen does body fat absorb compared to blood cells?
5 times more
Body fat has a higher affinity for nitrogen than blood cells.
What is the affinity of carbon monoxide (CO) to hemoglobin compared to oxygen?
200 times
CO binds to hemoglobin much more effectively than oxygen.
What happens to the appearance of objects in clear water versus turbid water?
In clear water, objects appear larger and closer; in turbid water, they appear far and small.
This phenomenon is known as visual reversal.
What is the formula for gauge pressure (FGV)?
FGV = FV × P
P can be gauge or absolute depending on the situation.
What is Boyle’s Law?
At constant temperature, pressure is inversely proportional to volume: P × V = K
This law describes the relationship between the pressure and volume of a gas.
What is Charles’ Law?
For a given mass of gas, either pressure or volume is directly proportional to absolute temperature.
P α T at constant volume; V α T at constant pressure.
What does Dalton’s Law state?
The total pressure exerted by a mixture of gases is equal to the sum of the pressures of each gas.
Pt = P1 + P2 + P3.
What is Henry’s Law?
The amount of gas dissolved in a liquid at a given temperature is directly proportional to its partial pressure.
This principle is key in understanding gas solubility.
How does temperature affect the solubility of gases?
Lower temperature increases solubility; higher temperature decreases solubility.
For example, boiling kettles release gas as temperature increases.
What is the relationship between atmospheric pressure and nitrogen solubility in the human body?
At atmospheric pressure, 1.25 grams or 1 litre of nitrogen is dissolved in the human body.
This is important for divers to understand nitrogen uptake.
What is supersaturation in diving?
Supersaturation occurs when gas dissolves out of the liquid and causes decompression illness (DCI).
This is a critical concept in managing dive safety.
What is the capacity of an atypical bail out bottle?
2.5 m³ or 90 ft³ of gas
Understanding equipment capacity is essential for dive planning.
What is the formula for converting Celsius to Fahrenheit?
F = (C × 1.8) + 32
This formula is useful for temperature conversions.
What is the density of fresh water?
1000 grams/litre or 62.5 lbs/ft³
The density of seawater is approximately 1030 g/L.
What is the average blood volume in the human body?
5-6 litres
Blood volume is crucial for understanding physiological responses.
What is the primary component of red blood cells?
Hemoglobin
Hemoglobin is essential for oxygen transport in the blood.
What is the role of white blood cells?
They remove dead cells and debris
White blood cells are crucial for the immune response.
What is the average lung capacity in litres?
6 litres
Lung capacity can vary based on individual health and fitness.
What is the average respiratory rate for a male at rest?
12 breaths per minute
This rate can change with activity level.
What is the main function of the central nervous system (CNS)?
To control and coordinate body functions
The CNS includes the brain and spinal cord.
What is the definition of barotrauma?
Pressure injury due to changes in ambient pressure
Commonly experienced by divers during ascents and descents.
What is the Valsalva maneuver used for?
To clear the ears
This technique helps equalize pressure in the ears.
What is the maximum partial pressure of carbon dioxide (CO2) in a chamber and bell?
10 mb
Monitoring CO2 levels is important for safety during dives.
What are the symptoms of acute oxygen poisoning?
Visual disturbance, tunnel vision, hearing problems, nausea, twitching, dizziness, convulsions, and coma
Awareness of these symptoms is critical for divers.
What is the treatment for decompression illness (DCI)?
Recompression and decompression using appropriate therapeutic tables
Timely treatment increases the chances of recovery.
What is nitrogen narcosis?
A condition caused by high nitrogen levels affecting cognition and motor skills
It typically occurs below 30 meters.
What is the definition of hypoxia?
A state of insufficient oxygen in the body
It can lead to unconsciousness and requires immediate action.
What is the relationship between body fat and nitrogen absorption?
Nitrogen dissolves 5 times faster in fat tissues than in water
This affects saturation levels and dive planning.
What are the two types of decompression illness (DCI)?
Type 1 (pain only) and Type 2 (serious, affecting CNS)
Understanding the types helps in diagnosis and treatment.
What is the average metabolic consumption of oxygen in a chamber per minute per diver?
0.5 litres
Monitoring oxygen consumption is crucial for dive safety.
What are the symptoms of hydrogen sulfide exposure?
Cherry red complexion, headache, dizziness, nausea, confusion, shortness of breath, unconsciousness.
What is the characteristic smell of hydrogen sulfide at lower concentrations?
Bad egg smell.
What happens to the sense of smell at higher concentrations of hydrogen sulfide?
No smell as sense organ gets damaged.
What is hypothermia?
A condition where body core temperature falls below 37°C.
What is the serious threshold for a fall in body core temperature?
A 2°C fall is serious hypothermia.
What are the critical temperatures for hypothermia?
- Shivering at 36°C
- Collapse at 30°C
- Death at 25°C
What is the rule regarding hypothermic victims?
Never assume a hypothermic victim is dead until they are warm and dead.
What is hyperthermia?
A condition where body core temperature exceeds 39°C.
What is the typical drowning time frame for death?
Death occurs in 4-5 minutes.
What is secondary drowning?
A condition caused by liquid in lungs, leading to complications after initial drowning.
What is dry drowning?
Water not in lungs because epiglottis closes.
What is wet drowning?
Water in lungs.
What does IMCA stand for?
International Marine Contractors Association.
What is the IMCA D 010 code related to?
Diving procedures.
What should be done after a diving incident?
Recording of diving should be kept for a minimum of 48 hours and until investigation is complete.
What are the flying restrictions after no-stop dives?
- Short flights: 2 hours
- Long flights: 8 hours
- 24 hours for longer dives.
What is the safety factor for man riding systems?
8:1.
What should diver umbilicals be tied to?
To keep the diver 5 meters away from thruster or suction.
What is the color code for oxygen cylinders?
White.
What is the maximum allowable temperature for gas cylinders?
45°C.
What is a golden rule for gas analysis?
Analyze before putting online.
What are the maximum allowable PPM in breathing air for CO?
15 PPM.
What is the safe minimum distance from Iridium IR 192?
8 meters.
What should be done in case of a miss fire with explosives?
Wait 30 minutes before handling.
What is the maximum depth for air and nitrox diving?
50 meters.
What is the minimum team requirement for surface supplied diving?
5.
What is the maximum bottom time for mixed gas below 50 meters?
30 minutes.
What is the responsibility of the radio supervisor?
To be responsible for the radiation.
What is the requirement for the oxygen reserve for diving?
90 m³ of O2 reserve for therapeutic use.
What should be avoided during decompression?
Any hard physical work.
What action should be taken if there is a loss of communication underwater?
Give line signals and terminate the dive.
What is the purpose of a contingency plan during decompression?
To recover a diver who has been accidentally delayed to leave the bottom.
What should be done if both gas supplies fail?
Open bail-out and surface immediately.
What should be done if a diver becomes unconscious in water?
Switch to secondary gas supply and send standby diver.
What is required for hyperbaric oxygen?
Personal required
Hyperbaric oxygen therapy often requires trained personnel for safe administration.
What are the different types of diving systems mentioned?
- Surface supplied diving
- Surface mix gas
- Closed bell
These systems are used in various underwater operations.
What does MSDS stand for?
Material Safety Data Sheet
MSDS provides safety information about materials used in workplaces.
What is the purpose of the chamber in diving operations?
Sufficient air to pressurise both locks of DDC to max possible treatment depth and to complete three decompression cycles as reserve
This ensures safety during decompression procedures.
How many independent sources must air be supplied from?
Two independent sources
This is crucial for redundancy in air supply during diving operations.
What is the classification for loss of position due to a single fault?
Class I
Class I indicates that loss of position may occur with a single fault.
What is the definition of Class II in terms of loss of position?
Single fault of an active component loss of position should not occur
Class II systems are designed to prevent loss of position despite single faults.
What is required for Class III systems regarding loss of position?
Loss of position should not occur even during completely burnt or flooded single compartment
Class III systems have the highest reliability standards.
What is mutual interference in DP vessels?
Occurs when DP vessels are working close
This can affect the performance of dynamic positioning systems.
What should Class II systems have for redundancy?
A redundant engine which automatically takes over in the event of fire or failure
This is essential for maintaining operational safety.
How many independent engine rooms should Class III systems have?
Two independent engine rooms
This is a requirement for enhanced safety and reliability.
What is the maximum angle for the taut wire in DP operations?
15 degrees
Exceeding this angle can compromise the effectiveness of the taut wire system.
What does the Artemis system consist of?
- Two antenna units
- One fixed
- One mobile
The fixed antenna is battery powered for installations, while the mobile unit is on the vessel.
What should be done during radio silence for wire line explosive work?
Artemis system should be switched off
This is to prevent interference during sensitive operations.
What can cause errors in the Artemis system?
- Obstructions
- Low battery of the fixed system
These factors can affect the accuracy of position referencing.
What is the function of hydroacoustic position references?
Acoustic signals transmitted from transponders on seabed and received by a transducer at the hull
This technology is critical for underwater positioning.
What should be the distance of a beacon from a structure?
Not closer than 10 meters
This distance helps avoid interference from structures.
What is the significance of digital global positioning systems in diving operations?
Satellite-based GPS system to be compared by a known location to get accurate location
GPS is essential for precise navigation and positioning underwater.
What should be done to maintain anemometers during diving operations?
There should be two anemometers at different locations with separate supply cables
This redundancy helps ensure accurate wind speed and direction measurements.
What does SIMOPS stand for?
Simultaneous Operations
This refers to conducting multiple operations at the same time, which requires careful coordination.
What is the maximum movement of a vessel with a diver in the water?
10 meters with 5 meter stops
This limit is set to ensure diver safety during operations.
What does a yellow DP alarm indicate?
Degraded ops status; one or more redundant DP equipment has failed
This requires immediate attention to maintain operational integrity.
What does a red DP alarm signify?
Emergency status; loss of position
This is a critical situation that demands urgent corrective actions.
What is the maximum lock-out time for a two-man bell diving operation?
Max 4 hours, with a possible extension of 30 minutes
This extension requires recorded agreement with the diver.
What is the standard for breathing air purity?
- O2: 21%
- Oil: 0.5 mg
- CO2: 500 ppm
- Water: 25 mg/m3
- CO: 3 ppm
These standards ensure a safe breathing environment for divers.
What should be done every six months for bail-out bottles?
Remove pillar valve and check for water content or corrosion
Regular maintenance is critical to ensure the functionality of safety equipment.
What is the minimum medical oxygen purity required?
99.5% minimum
This level is essential for effective medical treatment underwater.
What is the maximum bell run time for a three-man bell?
Max 8 hours
This limit is set to ensure diver safety during extended operations.
What is required for diving operations in terms of first aid qualifications?
Every diver should qualify in first aid with a renewal in 3 years
This ensures that divers are prepared for emergency situations.
What is the maximum lockout time according to DMAC 20?
BELL LOCKOUT TIME
What is the maximum duration for SAT as per DMAC 21?
28 DAYS
What is the exception for SAT intervals in DMAC 21?
50% OF SAT TIME OR 10 DAYS, WHICHEVER IS LESS, MAX OF 182 DAYS A YEAR
According to DMAC 22, what percentage of DCI symptoms shows within 4 hours?
95%
What is the maximum distance a diver should be after SAT according to DMAC 22?
20 MIN DISTANCE UP TO 4 HOURS AND 2 HOURS DISTANCE FOR 12 HOURS
What is the purpose of HEO2 in treatment as per DMAC 23?
USE OF HEO2 FOR TREATMENT
What is the requirement for analyzers in monitoring as mentioned in DMAC 23?
SUFFICIENT ANALYZERS FOR CONTINUOUS MONITORING WITHOUT CROSS CONNECTION
How is oxygen treated when it exceeds 25% according to DMAC 23?
TREATED AS 100%
What is the capability requirement for a closed bell as per DMAC 23?
CAPABLE OF SUSTAINING TRAPPED DIVERS FOR 24 HRS
What is the minimum height requirement for a basket in DMAC 23?
MORE THAN 2 METERS HEIGHT
What should divers avoid approaching according to DMAC 23?
ANY PIPELINE WHICH IS PRESSURIZED AND UNDER TEST
What is the minimum uninterrupted rest requirement during SAT?
AT LEAST 12 HRS UNINTERRUPTED REST IN 24 HRS
What should be used when opening a flood valve?
DEFFUCERS
What is the requirement for well head safety according to DMAC 23?
DOUBLE BLOCK AND BLEED
What may need to be switched off as per DMAC 23?
ICCP
What environmental conditions should be considered when working near a flare?
WIND SPEED AND DIRECTION
What is the minimum duration habitats need to keep divers alive?
48 HRS
What color background is mandatory with white symbols?
BLUE BACKGROUND
What is the prohibition sign color combination?
RED BORDER AND CROSS ON BLACK SYMBOL
What colors indicate a warning sign?
YELLOW AND BLACK
What is the maximum CO2 level as per DMAC 23?
5 MB, 0.5%, 5000 PPM, 500 ML
Below what percentage of O2 will fire not take place?
8%
