General Study Flashcards
1
Q
How many gallons are there in 1 cubic meter of fresh water?
A
264.172 gallons
2
Q
What is the formula to convert Fahrenheit to Celsius?
A
(°F - 32) ÷ 1.8 = °C
3
Q
What is the formula to convert Celsius to Fahrenheit?
A
(°C x 1.8) + 32 = °F
4
Q
How do you convert parts per million (ppm) to percentage (%)?
A
ppm ÷ 10,000
5
Q
What is the maximum carbon dioxide partial pressure limit in a chamber?
A
5mb or 0.005 ba or 5,000 ppm
6
Q
What is the maximum carbon dioxide partial pressure limit in a bell?
A
20mb or 0.02 ba or 20,000 ppm
7
Q
What is the equivalent of 1 atmosphere in mm Hg?
A
760 mm Hg
8
Q
What is the conversion from Celsius to Kelvin?
A
°C + 273
9
Q
What is the conversion from Fahrenheit to Rankine?
A
°F + 460
10
Q
What is the air consumption on bail-out in Norway?
A
62.5 L/min
11
Q
What is the weight of 1 gallon (imp) of fresh water?
A
10 lbs.
12
Q
What is the minimum time before flying at cabin altitude above 2000’ (600m)after a no stop dive?
A
18 hours
For short flights (less than 3 hours), the time is reduced to 18 hours, while for longer flights, it extends to 24 hours.
13
Q
What is the minimum time before flying after all other air and nitrox diving (less than 4 hours under pressure)?
A
12 hours below 2000’ (600m) 24 hours all other flights
.
14
Q
What is the minimum time before flying after heliox saturation diving (more than 4 hours under pressure)?
A
12 hours for flights less than 2000’ (600m) 24 hours all other flights
15
Q
What is the minimum time before flying after air, nitrox, or trimix saturation (more than 4 hours under pressure)?
A
24 hours 2000’ (600m) 48 hours all other flights
16
Q
What is the recommended minimum time from completion of therapy too flying at a cabin altitude of more than 2000 (600m)’?
A
72 hours
This applies to cases with immediate and complete resolution of symptoms.
17
Q
Fill in the blank: The minimum time before flying @ 2000’ (600m) or under after a total dive time under pressure of less than 60 minutes is ______.
A
2 hours
18
Q
What is the principle of colorimetric gas analysis?
A
Crystals in the tube change colour by chemical reaction, and gas content is read off against a scale on the side of the tube.
This method has a reading accuracy of 80%
19
Q
How is the true percentage of gas content calculated when readings are taken inside a chamber?
A
True percentage is found by dividing Surface Equivalent Percentages (SEP) by absolute pressure.
SEP is not the true reading; it is affected by the pressure in the chamber.
20
Q
What is the function of a quartz dumbbell in paramagnetic gas analysis?
A
The quartz dumbbell is suspended in a magnetic field and deflects due to the attraction of paramagnetic oxygen, allowing for measurement of oxygen content.
The deflection is measured by a reflected beam of light across a split photocell.
21
Q
What is the basic operation of polarography in gas analysis?
A
Oxygen in the sample is absorbed by the electrolytic jelly, causing a current to flow between two electrodes, which gives a measurement of oxygen content.
The electrolytic jelly used in these cells is corrosive.
22
Q
What is the expected cell life for a B1 (Brown) fuel cell?
A
6 months cell life.
It has a 90% scale readout in 5 seconds response.
23
Q
What is the expected cell life for a B3 (Red) fuel cell?
A
18 months cell life.
It has a 90% scale readout in 15 seconds response.
24
Q
What is the principle of infra-red CO2 electrical analysers?
A
CO2 absorbs infra-red light waves, and temperature comparison between two chambers indicates CO2 content.
One chamber contains non-CO2 gas, while the other contains the sample.
25
What should be used instead of silica gel for drying samples in CO2 analysis?
Potassium Permanganate.
## Footnote
Silica gel absorbs CO2, which affects the readings.
26
Fill in the blank: The reading accuracy of colorimetric gas analysis is _______.
80%
27
What is ZONE 0 in diving operations?
High risk area - Air/Gas mixture always present
28
What does ZONE 1 indicate?
An area in which an explosive gas mixture is likely to occur
29
What is the risk level of ZONE 2?
Explosive gas mixture unlikely risk unless gas leak
30
What documents must divers have in their possession when arriving on a job?
* LOGBOOK
* MEDICAL CERT
* FIRST AID CERT (North Sea)
* DIVER TRAINING CERT
31
What does HASAWA stand for?
Health and Safety at Work Act 1974
32
What is SI 2002 - 1587?
The Merchant Shipping (Diving Safety) Regulations 2002
33
What does SI 1997 - 2776 refer to?
The Diving at Work Regulations
34
List three classification societies.
* American Bureau of Shipping (ABS)
* Bureau Veritas (BV)
* Det. Norske Veritas (DnV)
35
Fill in the blank: The Diving at Work Regulations is SI _______.
1997 - 2776
36
IMCA D050 - MINIMUM AIR & 02 REQUIREMENTS for Air Diving?
Air to be in containers or come from 2 independent dedicated sources. Rig air is not normally allowed.
One compression of twin lock chamber to maximum treatment depth 50 msw.
Two emergency dives to full intended working depth.
Three complete surface decompression cycles (SurDO2)
Plus 90m3 of O2 reserved for therapeutic use only
37
What is the maximum allowable oil content in air according to BS EN 12021:2014?
Less than or equal to 0.5mg/m³
## Footnote
This refers to droplets or mist.
38
What is the maximum allowable concentration of CO in air according to BS EN 12021:2014?
Less than or equal to 5ml/m³ (5 ppm by volume)
## Footnote
This standard ensures safety in diving operations.
39
What is the maximum allowable concentration of CO2 in air according to BS EN 12021:2014?
Less than or equal to 500ml/m³ (500 ppm by volume)
## Footnote
High levels of CO2 can be dangerous for divers.
40
What does BS EN 1089-3:2004 cover?
Colour coding of gas cylinders
## Footnote
It includes requirements for marking the chemical formula and gas content percentages.
41
What is the required diameter for marking quads/trailers according to BS EN 1089-3:2004?
20 cm (8 inches)
## Footnote
This applies to disks or hatch lines.
42
According to SI 2776/1997, what is the maximum depth for surface diving?
50 msw
## Footnote
This regulation pertains to safety in diving operations.
43
What must be present on all offshore/pipeline diving jobs according to Diving at Work Regulations?
Decompression chamber
## Footnote
The chamber must be twin lock with enough room for 2 divers to lie down in comfort.
44
What is the maximum pressure for oxygen reduced at source in diving operations in Norway?
No more than 40 bar
## Footnote
The aim is to keep oxygen levels as low as possible.
45
What is the reporting requirement for accidents resulting in loss of 7 days or more work?
Must be reported under RIDDOR
## Footnote
This falls under the Reporting of Injuries, Diseases & Dangerous Occurrences Regulations 1995.
46
What is required when serious DCI occurs according to HSE regulations?
Must be reported within 3 days
## Footnote
This is the licensee's responsibility.
47
What defines a diving operation according to Diving at Work Regulations?
When the diver enters the water or a chamber pressure exceeds 100 mb (= 1msw)
## Footnote
This is crucial for establishing safety protocols.
48
What must cylinders be marked with according to BS EN 1089-3:2004?
Chemical formula and gas content percentages
## Footnote
This helps in identifying the contents for safety and compliance.
49
What is the significance of gauge testing for cylinders?
Conducted every 6 months
## Footnote
This is essential for safety and compliance with regulations.
50
What is the frequency for testing and examining all plant and equipment used in a Diving Operation?
6 monthly
## Footnote
A certificate must be issued by a competent person.
51
Who is included in Category 1 of competent personnel?
A diving or life support supervisor appointed by the diving contractor
## Footnote
Competent to carry out or supervise various examinations and tests.
52
What specific tests can a diving supervisor perform?
Pressure leak tests on pressure vessels
## Footnote
Can also be performed by any other competent person specializing in such work.
53
Who can be classified as Category 2 personnel?
A technician or other person specializing in such work
## Footnote
May be an employee of an independent company or the equipment owner.
54
What defines Category 3 personnel?
A classification society or insurance company surveyor, or Chief Engineer certified in accordance with IMCA C 002
## Footnote
May also include 'in-house' chartered engineers or equivalent.
55
What is required for Category 4 personnel?
Manufacturer or supplier of the equipment, or a technician fully trained and certified for the specific operation
## Footnote
Must have access to necessary testing facilities.
56
What is the visual inspection requirement for Diving Chambers and Bell?
6 monthly visual inspection
## Footnote
Followed by more extensive inspections at specified intervals.
57
What is the internal and external visual inspection frequency for Diving Chambers?
Every 2.5 years
## Footnote
Includes a gas leak test at full working pressure.
58
What is the maximum allowable gas leak rate during the 5-year internal overpressure test?
1% max in 24 hours
## Footnote
This is part of the testing protocol for Diving Chambers.
59
What is the maximum saturation duration allowed for diving operations in Norway?
14 days + 7 extension
60
What should the oxygen level in a chamber not exceed?
25%
61
What must be done with oxygen lines in diving operations?
Hard plumb all O2 lines as far as possible (1m max flexible O2 approved whip)
62
How often should analysers be calibrated?
Every 24 hours or in accordance with the manufacturer's instructions
63
What is the minimum diameter required for a diver's lifeline?
8 mm
64
What is the minimum breaking strain for a diver's lifeline?
At least 500 Kg
65
According to Norwegian regulations what is the required bailout supply for divers?
Sufficient to give 10 mins supply (Based on 62.5 L/min RMV)
66
What must be used to gain access to water if a diver is tended from more than 5m above sea level?
A basket or wet bell
67
If a ladder is used for diving access, how far must it extend below water?
At least 2m
68
What should be done with all gases over 25% oxygen?
Treat as pure O2
69
How long must Pressure Vessels certificates be kept?
Lifetime of equipment
70
What is the duration for keeping General Maintenance Records?
7 years or life of equipment if greater
71
What is the test duration for Diving Chambers?
2 year pressure leak test
72
What is the hydrostatic test duration for compressors?
5 years
73
What is the hydrostatic test duration for pipework?
10 years
74
How often must gauges be tested?
6 monthly
75
Name four reference systems used in dynamic positioning.
* Taut Wire
* Artemis
* Acoustic
* Satellite (DGPS)
76
What does the 'Mobile Antenna' refer to in the Artemis system?
Antenna on the vessel
77
What does the 'Fixed Antenna' refer to in the Artemis system?
Antenna on the Jacket, Shore, Fixed Location
78
What equipment is used in the Acoustic system?
* Transducer under Ship
* Transponder on seabed
79
What is a potential problem with Taut Wire systems?
Shallow water or fouled structures
80
What is a potential issue with the Artemis system?
Blockage of Signal
81
What affects the reaction time of Acoustic systems in deeper water?
The longer time it takes to react
82
Fill in the blank: All equipment must be kept clear of wires, i.e. Tugger/Basket min ______ above and ______ to the side of any subsea equipment.
5m, 10m
83
What is the minimal reference system for diving according to IMCA ACoPs?
3 Systems 'on line'
## Footnote
Also referred to as 2 + 1 in UK Diving Regulations.
84
What does a Green Light indicate in alert levels?
Normal Operation Status
85
What does a Yellow Light signify in alert levels?
Degraded Operational Status - Discuss with Master
86
What does a Red Light (Flashing) indicate in alert levels?
EMERGENCY STATUS. No negotiation, all divers up & out of water
87
What does a Green Light mean in collision levels?
No risk of collision exists
88
What does a Yellow Light signify in collision levels?
Possible risk of collision exists
89
What is the maximum thruster power that must not be exceeded for more than brief periods?
80% of power capability
90
What is the most common cause of DP incidents?
OPERATOR ERROR
91
What is the visibility recommendation for surface-oriented diving?
Not recommended for surface orientated diving when visibility under 0.5 nautical miles
92
How much more dangerous is AC current compared to DC current?
5 times more dangerous
93
What is the maximum voltage allowed underwater for DC without ELCBs?
24v DC
94
What is the maximum voltage allowed underwater for AC with ELCBs?
110v AC
95
What is the preferred maximum voltage on deck and in workshops?
110v AC via Transformer
96
What type of electrical supply is recommended for underwater use?
DC in preference to AC
97
What is the primary passive defense against electric shock?
Insulation
## Footnote
Insulation serves as a barrier to prevent electric shock in various environments.
98
What is the approximate weight of a 16 Cylinder quad?
1.5 tonnes
99
What is the approximate weight of a 48 Cylinder quad?
4 tonnes
100
What is the maximum working pressure for water jetting?
8000 psi
101
What is the working pressure range for grit entrainment to SA 2½2?
210 - 500 bar (4000 - 8000 psi)
102
What is the minimum retro lance length for water jetting?
60 cm
103
What is the maximum trigger pressure in water jetting?
12 PI (Pound inches)
104
What is the most common cause leading to fires?
Bad housekeeping
105
What is the team size for Surface Diving (air)?
5
106
What is the team size for Surface Diving (Mixed Gas)?
6
107
What is the team size for Saturation Diving?
9
108
What color represents Helium in IMCA gas cylinder color codes?
Brown
109
What color represents Helium Oxygen mixtures?
Brown & white quarter
110
What color represents Industrial Oxygen?
White
111
What color represents Carbon Dioxide?
Grey
112
Who holds the ultimate responsibility onboard for radiation safety?
Radiation Protection Supervisor (RPS) with letter of appointment
113
Who is the emergency contact ashore for radiography?
HSE Duty Radiography Officer or Radiation Protection Adviser (RPA)
114
What is the common radiation source used in diving radiography?
Iridium (IR192)
115
How is radiation dosage measured?
Micro Sieverts (uSv)
116
What is the safe distance away underwater during exposure?
8 Metres
117
At what dosage do alarm badges illuminate?
25 micro Sieverts
118
What regulation governs ionising radiations in the UK?
The Ionising Radiations Regulations 1999
119
Which regulation focuses on the management of health and safety at work?
The Management of Health & Safety at Work Regulations 1992
120
What act regulates radioactive substances in the UK?
The Radioactive Substances Act 1993
121
What is the Diver Gas Consumption rate for recovery systems?
5 LPM or 0.18 cfm
## Footnote
This rate indicates the consumption for divers utilizing recovery systems.
122
What is the Diver Gas Consumption rate on bail-out (Norway)?
62.5 LPM
## Footnote
This figure reflects the bail-out gas consumption specific to Norway.
123
What is the Chamber BIBS Consumption rate?
20 LPM or 0.7 cfm
## Footnote
This consumption rate is measured for the Chamber BIBS system.
124
What is the metabolic oxygen consumption in DDC's per diver?
30 L/hour (0.5 LPM) or 0.72 m3 /day
## Footnote
This indicates the amount of oxygen consumed metabolically by a diver in a DDC.
125
What is the rate of CO2 absorption by Soda Lime per Kg?
120L of CO2 per Kg
## Footnote
Each diver typically uses about 6Kg of Soda Lime per day.
126
What are the typical oxygen partial pressure limits for chamber emergency gas BIBS?
0.2 to 0.8 bar
## Footnote
These limits are crucial for ensuring safety in emergency gas situations.
127
What are the typical oxygen partial pressure limits for saturation storage?
0.35 to 0.45 bar
## Footnote
This range is essential for maintaining safe saturation storage conditions.
128
What are the typical oxygen partial pressure limits for saturation dive or decompression?
0.5 to 0.8 bar
## Footnote
These pressures are important for saturation diving and decompression processes.
129
What are the typical oxygen partial pressure limits for gas diving therapeutic treatment (BIBS)?
2.2 to 2.8 bar
## Footnote
These limits are critical for therapeutic treatments using gas diving systems.
130
What is the average bell scrubber duration?
20 - 30 man/hours
## Footnote
This duration indicates how long a scrubber can effectively function for divers.
131
What does EH 75/2 document refer to?
Occupational Exposure Limits in Hyperbaric Chambers.
132
What is the common reply frequency of Diver Handheld Locator?
37.5 KHz.
133
How often should chambers be cleaned?
Every 24 hours.
134
What is the purpose of On Board Gas (OBG) in diving?
To provide sufficient gas for divers and bellman to last 30 minutes at the maximum excursion depth of the dive.
135
What is the first action of the Bellman in case of emergency unconscious diver recovery?
'OBG ON'.
136
What should be done if a diver experiences an ear infection?
Stop diving, take a swab, and send it ashore for analysis.
137
What does SOLAS stand for?
Safety Offshore Life at Sea.
138
What must the HRV be colored according to UK legislation?
International orange.
139
What are the requirements for marking HRV as per UK legislation?
Must be clearly marked with 3 signs visible at all times.
140
How long must the HRV carry a supply of fuel according to UK legislation?
For a minimum of 4 days (96 hours).
141
What is the interrogation frequency for Channel A?
38.5 KHz.
142
What is the interrogation frequency for Channel B?
39.5 KHz.
143
IMCA D050 - MINIMUM MIXED GAS & 02 REQUIREMENTS
BOUNCE DIVING
One Emergency dive to full intended depth
Two Chamber compressions to transfer depth with enough supplied gas to carry out any necessary flushing for two complete decompressions (if using air it should be container stored or be from TWO independent dedicated sources. Not to be rig air).
One Chamber pressurisation to maximum diving depth and carry out full saturation decompression in the event of medical emergency.
Enough Oxygen for saturation decompression, plus 90m3 for therapeutic use.
144
Minimum Gas and O2 requirements SATURATION DIVING
Enough gas for intended bell run plus same amount in reserve. (This does not include bell on-board gas).
Enough gas to pressurise all required chambers to storage depth plus same amount in reserve. This reserve to be maintained throughout sat.
Two full decompressions from storage depth plus that required for daily use in leakage, locks, toilet etc.
Enough Oxygen for metabolic consumption and maintaining PPO2 during the decompression plus same amount in reserve.
Plus 90 m3 of Oxygen for therapeutic use only.
145
BELL - Emergency unconscious diver recovery - last thing before leaving Bell?
Flood trunking.
146
What emergency capability must the bell have?
24 hour emergency capability
147
What is the frequency for thorough visual examination of HEL's?
6 monthly
148
What are the requirements for yearly function tests of HEL's?
Static load test at 1.5 x maximum SWL plus NDE of critical items
149
What is the frequency for visual examination of Survival Packs?
6 monthly
150
Doing so Good
151
What is the frequency for checking hyperbaric evacuation system survival packs?
Every 3 years
152
How long are Diver records kept for?
5 years
153
What is the taut wire operating radius in 35m of water?
9.31 meters
.266 x the depth
154
At what percentage of O2 is it considered complete combustion?
21 %
155
What is the vital capacity of the lungs?
The maximum amount of air a person can exhale. Avg male is 5000 ml
156
What does BSP stand for?
British standard pipe
157
How often should hydraulic oil be changed on man riding equipment?
Every 12 months
158
What is the blue alert in the DP system?
Advisory status
Where any of the Green conditions are not met
159
What is the minimum length of
Electrical lead for LSP?
20 M
160
To meet the required standard of safety, a weak link device must be capable of?
1) supporting a fully equipped working diver and/or their umbilical against current or other forces
in water
2) breaking/releasing reliably on application of an appropriate load, considered to be in the region
of 70 kg
3) withstanding environmental conditions, such as mud, water, grease etc.
Any weak link should be used in conjunction with a device capable of manual release under tension by
the diver, such as an over-centre snap shackle which also allows the attachment to swivel
161
List three sources of contamination that divers may encounter.
* Drill mud and cuttings
* Chemicals being recovered
* General contamination from heavy metals or radioactivity
162
What are the three main hazards to consider when diving in contaminated waters?
* Direct contamination of the diver
* Contamination of the diver's equipment
* Contamination of the atmosphere in the diving bell or DDC
163
What could be released when breaking containment of sealed or abandoned assets?
H2S or biofouling
## Footnote
Biofouling is created from the organic breakdown of internal materials over time.
164
What gases can biological microbes produce that affect breathing gas supplies?
H2S
165
Name three examples of heavy metals that may be encountered in contaminated waters.
* Mercury
* Cadmium
* Arsenic
166
What are the required dimensions for signs on the exterior of a hyperbaric lifeboat?
1200 mm long x 450 mm high
167
Magneto dynamic oxygen analysers work by?
Dumbbell low power particle in a strong polar magnetic field.
168
Babinski reflex is found where?
Planter
169
What marking on a cylinder is highlighted with a distinctive colour patch (usually grey/silver)?
Hydrostatic test date
170
List the sequence of air filters in order of precedence on a LP compressor?
Water trap
Particle
Moisture (silica gel)
Co2 (soda sorb)
oil + water vapour (activated illumina)
CO (Activated charcoal)
