IMCA D0 22 Flashcards
IMCA promotes what four standards?
Health
Safety
Environment
Technical Standards
How does IMCA promote it’s 4 standards?
Information notes
Codes of practice
Safety flashes
Are IMCA members self regulating?
Yes
How are IMCA members self regulating?
They commit to following relevant guidelines.
Willing to be audited by clients to those guidelines
What are the two core activities of IMCA?
1) Competence & Training
2) Safety, Environment & Legislation
What are the 4 divisions of IMCA?
1) Diving
2) Marine
3) Offshore survey
4) Remote systems & ROV
What are the 5 regions of the world IMCA cover?
1) Asia Pacific
2) Central & North America
3) Europe & Africa
4) Middle East & India & South America
Inside the 12 mile limit what 5 activities are specifically excluded from the IMCA International Code of Practice D0 14?
1) Civil
2) Inshore
3) Inland
4) Habour works
5) Activities not conducted from a vessel or structure associated with oil & gas / renewable industries
If national standards are more stringent that DO14 they take precedence:
True of False
True
Diving supervisors in charge of each part of the operation have direct
responsibility for diving operations carried out under their control?
True or False
True
The examination and training for an air diving supervisor does not included surface mixed gas
diving techniques.
True or False?
True
A diving superintendent or senior supervisor is an appropriately qualified diving supervisor who is in overall charge of an operation - and is responsible for the dive.
True or False
FALSE
DIve supervisor is the responsible person.
How many hours to become an LST?
2400
IMCA offshore diving supervisor and life support technician certification schemes is DO..
DO13
All divers at work need to hold a suitable qualification for the work they intend to do. They will need
to have the original certificate in their possession at the site of the diving project.
Are copies accepted?
No
IMCA only recognises two grades of diver under the Code
What are these?
Surface Supplied
Closed Bell
Guidance on competence assurance and assessment: Diving Division is document CO..
C003
What is the D014?
International code of practice
What is DO13
Certification schemes for Diver Supervisor and LST
What is CO03
Competency assessment
What is the MKS system of measurement?
Systeme International:
Meter
Kilogram
Second
How many pascals = 1 bar
100,000 Pa = 1 bar
What is the FPS system of measurement?
Imperial System:
Foot, Pound, Second
1 imperial ton is how many lbs?
2,240 lbs
1 US ton is how many pounds
2000 lbs
1 therm is how many BTU
100,000
1 atm is how many FSW?
33 FSW
How many PSI in one ATM
14.7 psi
1 imperial gallon = how many US gallons?
1.2 US gallons
1 US gallon = is how many imperial gallons?
0.83 US gallons
How many feet are there in a meter?
3.281
How many feet in a cubic meter?
35.32
How many cubic feet are there in a meter?
28.31
How many pounds are in a kilogram?
2.204
How many bar in an atm?
1.01
How many psi in 1 bar
14.5
How to convert C to F?
C x 1.8 + 32 = F
How to convert F to C
F -32 / 1.8 = C
A DDC with a floodable volume of 6m3 is pressed from the surface to 30 msw. How much gas is used
18m3
A DDC is at 30 msw with 6% oxygen showing on the surface analyser. What is the pO2 at 30 msw?
0.24 pO2
A DDC is pressed from the surface to 30 msw using 6% oxygen. What will be the pO2 at 30 msw?
0.39 pO2
A commercial diver is calculated using how many litres and feet / min?
35 litres / min
1.25 ft3 / min
A commercial diver is calculated using how many litres and feet / min in an emergency?
40 litres / min
1.5 ft3 / min
62.5 Norway
1.8 ft 3 / min
Gas reclaim losses are calculated as how many litres / min?
5 litres / min
0.18 ft3 / min
diver is working at 20 msw for 4 hours. What volume of gas will he use?
The diver will use 25.2 m3 of gas
A diver is working at 100 fsw for 30 minutes. What volume of gas will he use?
The diver will use 151.2 ft3 of gas
The volume of a 64 bottle quad is 64 x 50 ltr is?
3.2 m3.
A 64 x 50 ltr quad contains gas at a pressure of 100 bar. What is the total volume of useable gas in the
quad?
320 m3
A dive is planned to 40 msw. The bail-out is charged to 200 bar. What pressure is available to the diver?
185 bar
Ambient + 10 bar for regulator
In practice, diving supervisors should allow a considerable margin of error and would normally change
over to a new gas quad when the pressures drops to
40 bar
A diver is working at 80 msw, breathing from a 16 x 50 ltr quad at a pressure of 150 bar. How long
could he work for (assume that the quad will be changed over at 40 bar)?
4 hours and 39 minutes
A quad contains 5,800 ft3 when it is at a pressure of 3,000 psi. How much gas does it contain when the
pressure is 1,800 psi?
3,480 ft3
A quad contains 5,800 ft3 when it is at a pressure of 3,000 psi. How much gas is available to the diver if
the quad was to be taken offline at a pressure of 1,800 psi?
2,320 ft3
A diver is working at 250 fsw. He is breathing from a quad which contains 22,500 ft3 of gas when it is
at a pressure of 3,000 psi. It is now at 2,750 psi. How long could the diver work for (assume that the
quad will be changed over at 500 psi)?
26 hours 13 minutes
An LP compressor supplies 30 ft3/min at 300 psi. The diver plans to work at 100 fsw. Is the air supply
sufficient (allow 10 atm for the operation of the regulator)?
The compressor delivers 300 psi, so the pressure is suitable
A lightweight LP compressor delivers 250 l/min at a pressure of 15 bar. Two divers are planning to
work at 30 msw. Is the air supply sufficient?
The compressor delivers 15 bar, so the pressure is suitable
But the compressor only delivers 250 l/min, so the volume is insufficient.
A bail-out bottle has a floodable volume of 8 ltr. How much time has a diver got if his surface supply
fails at 50 msw? The bail-out bottle is at a pressure of 200 bar.
6.13 minutes
A bail-out bottle has a floodable volume of 12 ltr. How much time has a diver got if his surface supply
fails at 200 msw (660 fsw)? The bail-out bottle is at a pressure of 180 bar.
2.12 minutes
After filling to 3,000 psi a bail-out bottle is at a temperature of 100°F. What will the pressure be when
the temperature drops to 40°F?
2,679 psi
A diver at 250 fsw is breathing a 15% mix. What is the ppO2 in his mix?
1.287 ata
In a chamber at 80 msw, the oxygen percentage reading is 4.5%. What is the ppO2 in the chamber?
405 mb
A diver at 125 msw is breathing a 4% mix. What is his ppO2?
0.54 bar
During a saturation dive at 600 fsw, divers require a ppO2 between 0.5 and 0.8 atm. What is a suitable
mix?
2.6% to 4.2%
If the ppO2 must lie between 1.2 and 1.6 bar, what is the greatest depth at which a 15% mix could be
used?
= 96.7 msw
What is the EAD formula in metric?
EAD = Nitrogen % x Absol Depth / 79 - 10 msw
What is the EAD formula in imperial?
EAD = Nitrogen % x Absol Depth / 79 - 33 fsw
A diver is breathing a 40:60 nitrox mix at 25 msw. What is the EAD?
The EAD is 16.6 msw, so use the next deepest table
A diver is breathing a 30/70 nitrox mix at 100 fsw. What is the EAD?
The EAD is 84.8 fsw, so use the next deepest table
You have an empty quad and you want to make 200 bar of 9%, using 2% and 12%. What pressure of
each gas do you need?
You need 140 bar of 12% and 60 bar of 2% to make 200 bar of 9%
You have 100 bar of 4% and you want to turn it into 10%, by pumping in 20%. What will the final
pressure of the mixture be?
160 Bar 10%
A chamber is to be pressurised to 90 msw, using 18% and 2%. The final ppO2 must be 600 mb. What
depth of 18% should be added to start the pressurisation?
13 msw
A chamber is to be pressurised to 250 fsw, using 16% and 2%. The final ppO2 must be 0.5 ata. What
depth of 16% should be added to start the pressurisation?
32.6 fsw
A chamber system has a volume of 40m3. What volume of gas would it take to pressurise it to 150 msw?
600 m3
A chamber system has a volume of 1,200 ft3. What volume of gas would it take to pressurise it to
500 fsw?
18,180 ft3
A chamber system has a volume of 30m3. It is to be pressurised to 90 msw, with 21 msw of 12% and
69 msw of 2%. What volume of each gas would be needed?
63 m3 of 12% and 207 m3 of 2%
A medical lock is 0.8 m long and 0.3 m in diameter. The chamber is at 160 msw. How much gas is used
when the lock is operated?
0.912 m3 of
1 msw of oxygen increases ppO2 by
0.1 bar
3 fsw of oxygen increases ppO2 by
0.09 atm
Nine divers are in saturation for 5.5 days. How much oxygen will they use in the chamber?
35.64 m3
1237 ft3
A decompression from 95 msw takes two days, with a ppO2 of 600 mb. There are two divers in the
chamber, and the chamber volume is 10 m3. How much oxygen is used?
16.98 m3
Six divers are in saturation for eight days at 110 msw, with a ppO2 of 400 mb. Before starting the
decompression, the ppO2 is raised to 600 mb. The decompression takes three days. The chamber
volume is 15 m3. How much oxygen is used?
72.84 m3
At the start of the shift, a chamber is at 145 msw and 32°C. During the shift, the temperature fell to
28°C. If the life support crew had not added gas to maintain depth, by how much would the depth have
decreased?
2 msw
Chamber 1 is at 320 fsw, with a ppO2 of 0.4 ata and a percentage of 3.74%. It is bled to 100 fsw. What
is the ppO2 at 100 fsw?
0.15 ata
Chamber 1 is at 97 msw, with a ppO2 of 400 mb. It is blown down to 130 msw, using 2%. What is the
ppO2 at 130 msw?
466 mb
After equalisation, Chamber 1 has a volume of 12m3 and a ppO2 of 480 mb. Chamber 2 has a volume
of 8m3 and a ppO2 of 400 mb.
448 mb
During a saturation dive, nine divers will live at 95msw for 10 days, including decompression. How
much absorbent would they use?
540 kg
What is soda lime (soda sorb made of?)
Calcium hydroxide
Describe the chemical process of scrubbing C02 using calcium hydroxide (soda lime)
Co2 absorbed by moisture reacts with the calcium hydroxide to form carbonic acid. An exothermic reaction (gives off heat).
How many kilos of soda sorb will each diver use per 24 hours?
6 kilos
How many liters of Co2 does a diver generate in a day?
720 liters
Equal to o2 consumption
How many liters of Co2 will 1kg of soda sorb adsorb?
120 liters
A chamber and bell are at 185 msw, with a ppO2 of 400 mb. For the dive, the bell is separated from
the chamber and blown down on 4% to a working depth of 200 msw. What is the ppO2 in the bell at
working depth?
460 mb
A chamber and bell are at 70 msw, with a ppO2 of 500 mb. For the dive, the bell is separated from the
chamber and blown down on 4% to a working depth of 90 msw. What is the ppO2 in the bell at working
depth?
580 mb
A diver takes a chemical sampling tube reading of 0.4% in the bell at 110 msw. What will be the reading
on the percentage surface analyser (i.e. the true percentage)?
0.033%
The bellman uses a chemical sampling tube to take a CO2 reading in the bell. The scale reading is 1.4%.
If the bell is at 400 fsw, give the true percentage of CO2, the pCO2 and the SEP.
True percentage = 0.107%
Partial pressure = 0.014 ata
SEP 1.4%
What IMCA document deals with minimum gas volumes?
IMCA D050
How is heat energy measured in the metric and imperial systems?
Metric: Joules or Calories
Imperial: BTU’s
What is the specific heat capacity of of substance?
Amount of energy it takes to raise the temperature of 1 kilo of the substance by 1 degree C
What are the 3 ways to transfer heat?
conduction, radiation, convection
How many times faster does water conduct heat that air?
24 times
How many more times conductive is Helium than air?
6 times
How many more times conductive his hydrogen than air?
7 times
A low hot water temperature with a high flow rate can transfer as much heat at a high temperature with a low flow rate to the diver.
True or False
True.
What is the rough calculation guide for hot water temp drop over the length of an umbilical?
Temp drop = Umbilical length / flow rate
Describe buoyancy
volume of water displaced x density of water
What is the density of sea water? (Metric & Imperial)
1.03 kg/l, or 1.03 t/m3 or 64.38 lbs/ft3.
What is the density of fresh water? (Metric & Imperial)
1.00 kg/l,
or 1.00 t/m3 or 62.5 lbs/ft3.
A diving bell displaces 5 m3 of sea water and weighs 4.8 tonnes. Is the bell positively buoyant?
Positive buoyancy = 0.35 tonnes
A diving bell displaces 180 ft3 of sea water and weighs 5.2 imperial tons. Is the bell positively buoyant?
Negative buoyancy = 0.03 tons
How much does diver weigh?
150 kg
A block of concrete, 2m x 2m x 3m, is lying on the seabed. The density of concrete is 2,400 kg/m3.
How much force is required to lift the block clear of the seabed?
16.44 tonnes
What is the maximum breaking force of a weak link?
70 kg
Maximum pO2 supplied to the diver on bailout
1.4 bar
Therapeutic treatment PPo2
1.6 to 2.8 bar
Other acceptable bailout mixes
Bottom mix
>350 mb (chamber mix)
IMCA Saturation (in water) PP02
0.5 to 0.8 bar
Saturation (in chamber) PPo2
0.35 bar to 0.5 bar
Maximum PPO2 for surface supplied diving
1.4 bar
Diver gas consumption from a bail-out bottle or other supply source in an emergency
40 l/min
1.5 ft3/min
Reclaim losses
5 l/min
0.18 ft3/min
Bell Co2 (Maximum)
20 mb
0.02 bar
2%
20,000 ppm
Chamber Co2 Maximum
5 mb
0.005 bar
0.5%
5,000 ppm
Co2 Poisoning PPM
40,000 PPM
Loss of consciousness PPM Co2
100,000 PPM
Anterior means
front of the body
posterior means
to the back
midline is
imaginary line down
the center of the body.
Superior means
towards the top
inferior means
towards the bottom
Proximal means
closer to
distal means
further away
carbon dioxide in the blood is dissolved as
carbonic acid
Carbonic acid levels in the blood stimulate breathing
True of False
True
dioxide poisoning is called
hypercapnia
Oxygen will only pass into the bloodstream if the pO2 (partial pressure or tension of oxygen) in the
lungs’ alveoli is higher than the pO2 in the blood in the capillaries in contact with the alveoli.
True or False
True
What is internal respiration
The exchange of oxygen and carbon dioxide at cellular level
What is external respiration
The exchange of oxygen and carbon dioxide in the lungs
Inadequate oxygenation of the cells is known as
Hypoxia
Total lack of oxygen is called
Anoxia
There are ….. organ systems in the body.
11
The 4 important to diving are
skeletal;
respiratory;
circulatory;
nervous.
How many bones in the human body
206 separate bones
How many vertebrae in the spine
26 vertebrae
Top 7 vertebrae in the spine known as
cervical vertebrae
Rapid pressurisation can cause discomfort or even pain in the joints is
compression arthralgia
Blood cells are created in
Bone marrow
How many sinus cavities are there in the cranium? (skull)
4
five principal body cavities
cranial cavity
spinal cavity
thoracic cavity
abdominal cavity
pelvic cavity
the pharynx is
throat
larynx is
voice box
food and liquids are normally prevented from entering the lower airway by
epiglottis
tubes are about 1mm in diameter in the lungs are known as
bronchioles
The bronchioles continue to branch, eventually terminating in grape-like clusters of tiny, hollow air sacs
known as
alveoli
In an adult male lung surface area area is about
70 m2
The alveoli are covered in a network of fine blood vessels called
capillaries
arterial gas embolism is
Rupture of aveloi wall allowing gas to enter bloodstream
Each lung is covered by a double layer of membranes
called
pleura
The two layers of the pleura are so close together that they are virtually in contact with each other.
They are separated only by a thin layer of fluid called
pleural fluid
pleural fluid acts as
lubricant
to allow the pleural membranes to slide over each other
If the space between the pleural membranes
becomes filled with gas is is known as a
pneumothorax
haemothorax is
blood between the two plural layers surrounding the lungs
De-oxygenated blood is carried to the lungs by
pulmonary artery
Oxygenated blood is carried from
the lungs back to the heart by the
pulmonary vein
exhaled gas contains about …%
oxygen
16%
The average adult male takes about …. breaths
12
Tidal volume is about …. ml of gas
500 ml
The total lung capacity is about ……. ml
6000 ml
in very deep breathing about
5000 ml of gas can be moved. This is known as the …… capacity of an individual
vital capacity
During normal respiration at rest, the body uses about ….. ml of oxygen per minute
250 ml
During exercise
oxygen use can be …… ml per minute or more.
1000 ml
IMCA D050 recommends using a consumption of …..ml per minute
500 ml
During normal breathing about ….ml of gas remains in the dead space
150 ml
Arteries carry
blood ….. from the heart
away
veins return blood ….. the heart
to
gas exchange with the tissues takes place from the
capillaries
There are how many blood circulation circuits.
two
The systemic circulation supplies all the
body
* except lungs
The pulmonary circulation passes only through the
…….
lungs
Haemoglobin carries about …..% of the oxygen with the remainder dissolved in the plasma
95%
leucocytes are
white blood cells
platelets preform what function
Blood clotting
The right heart
receives blood from the ………. circulation and sends to to the lungs
Systemic
left heart receives the oxygenated blood from the lungs and pumps it through the
systemic circulation to supply all the body tissues and then back to the right heart
True of False
True
…………. blood pressure is the pressure exerted against the walls of the arteries when the heart is contracted
Systolic
………… blood pressure is the pressure when the heart is
relaxed.
Diastolic
Optimum blood pressure is what?
120 / 80
Mild hypertension is what blood pressure ?
140 / 90
No radial pulse indicates a systolic blood pressure below what?
80 mmHG
Below …… the femoral pulse will not be detectable
70 mmHG
below ……. the carotid
pulse will not be detectable
60 mmHG
Capillary refill gives a quick indication of blood pressure in a casualty. How fast should a fingernail return to pink colour after it is blanched by pinching lightly?
2 seconds
The heart muscle is stimulated to beat regularly by a series of electrical impulses. Various circumstances
such as electric shock, hypoxia, severe hypothermia, electrolyte imbalance caused by near drowning,
trauma and a variety of medical conditions can cause this rhythm of electrical impulses to become
chaotic.
This is known as?
ventricular fibrillation
The normal heart rate may be anything from ….. to …….
40 to 80 bpm
Although there is a single, continuous nervous system it is convenient to subdivide it into the central
nervous system and the peripheral nervous system.
True of False
True
The organs of the central nervous system are covered by layers of membrane known as the …….
meninges
……….. fluid circulates around brain and spinal cord under the meninges
Cerebro-spina
The 3 principal parts of the brain are the…..
cerebrum, cerebellum and brain stem
The cerebrum is the largest part of the brain and controls…..
higher functions such as thought,
speech and voluntary movement.
The cerebellum lies beneath the cerebrum and is of similar shape but considerably smaller. It exerts
unconscious control over…
basic functions
The brain stem links into the spinal cord and also controls the …….
operation of the heart and lungs
The middle ear is connected to outside atmosphere via the …………. ……………
Eustachian tube
The ossicles transmit the vibrations to the ……… in the inner ear. The cochlea contains the hearing
sense organ, which transmits the information to the brain via the ………. nerve.
cochlea
auditory
fluid filled semi-circular canals which control ………..
balance
IMCA international code of practice DO14 that at least how many team members are diver medics
two
What is DMAC 15
Medical Equipment to be Held at the Site of an
Offshore Diving Operation
What is DMAC 28
The Provision of Emergency Medical Care
for Divers in Saturation
Barotrauma, is a …….
pressure injury
10 types of baraotrauma
Aural Barotrauma
Sinus Squeeze
Dental Barotrauma
Mask Squeeze
Nips
Helmet Squeeze
Pulmonary Barotrauma
Interstitial Emphysema
Pneumothorax
Arterial Gas Embolism
Nitrogen has an affinity for fat …… times that of fluids in the body
Five times
Nitrogen will saturate the body fluids within …… minutes. But it will take …….. hours to saturate fat.
60 minutes
Several hours
an air diver ascends from 10 msw to surface, about 65% of the dissolved nitrogen will have left his
body in …… and about 90% after …….. ………. He will not, however, be completely free of the
excess gas for 12 hours.
60 minutes
6 hours
DCI cases treated
within 30 minutes have a ……% success rate.
90%
A delay of 5 hours reduces the success rate to only ……%
50%
Pain only DCI is likely caused by bubble formation in
muscles or joints
Skin bends are caused by bubble formation in the …… …….. under the skin
Fat layer
Minor pains or twinges are often described as ‘niggles’ should be treated at DCI
True or False
True
If they resolve at depth then it’s a DCI
Serious DCI is caused by bubble formation in the central nervous system (CNS)
True of False
True
Spinal DCI, for example, is caused by bubble formation in the spinal cord or in the sheath covering the
cord. Typical symptoms are
Numbness or tingling
Pain around the waist,
Loss of bladder
Excessive tiredness
Weakness in the legs Paralysis
Cerebral DCI symptoms include
Irritability
Hallucination
Paralysis (one side)
Vestibular DCI is caused by bubble formation in the inner ear. The symptoms are
loss of balance,
Nausea
Vertigo.
Ringing ears.
‘Chokes’ is included as serious DCI because
it is immediately life threatening.
Caused by rapid decompression.
What are the symptoms
The diver is unable to breathe properly because large numbers of
bubbles have formed in the pulmonary circulation.
Osteonecrosis, is
patches of dead bone
During chronic oxygen poisoning, the lungs become congested, there is a fluid build-up and damage to
the capillaries. The first symptom is….
mild tickling, or irritation in the lungs and a slight cough
Sever chronic o2 poisoning symptoms include….
Severe and constant burning sensation on inhalation.
Persistent cough.
Extreme fatigue,
muscle aches,
headaches,
dizziness,
tingling and numbness in
the fingers and toes.
Acute oxygen poisoning symptoms
Vision
Ears (ringing)
Nausea
Twitching
Irritation
Dizziness
For DCI treatment in a chamber, the diver can breathe a pO2 as high as …… bar
2.8 bar
No attempt should be made to decompress a diver during a convulsion, even if a move is due. He will be unable to exhale and may suffer pulmonary barotrauma.
True or False
True
It is standard practice to
analyse gas before it goes to the diver and always have an on-line analyser, with audio alarms turned on…. why?
To avoid wrong gas going to the diver making him hypoxic or anoxic
Hypoxia is generally considered to occur when the pO2 is less than ….. mb
160 mb
Minimum PPo2 in the water is usually?
450-600 mb.
At what PPn2 does nitrogen narcosis generally occur
approximately 3.2 bar.
The symptoms of hypercapnia or carbon dioxide poisoning are
headache
sweating
increased respiration
feelings of apprehension
Carbon monoxide is typically found in the air supply from a….
faulty compressor or a compressor with a
badly placed air intake.
It may also be encountered in habitat welding
Carbon monoxide has an affinity to hemoglobin …… times more than oxygen.
200 times
Carbon monoxide poisoning symptoms are
cherry red complexion
What is the IMCA D021?
Diving in contaminated waters
What is IMCA DO31
Cleaning for oxygen service
Divers breathing heliox mixtures must have some form of active heating.
True of False
True
Past 150 meters divers must have a heated gas supply.
True or False
True
Normal body temperature is about
37°C
Shivering starts to occur at about
36°C
The clinical phases of progressive hypothermia can be classed as
- Mild body core temperature 35-34°C
- Moderate body core temperature 33-30°C
- Severe body core temperature < 30C
Rapid re-warming can cool the blood as it flows though the cold outer tissues
and cause a fatal temperature drop as it returns to the core.
True or False
True
Hyperthermia is considered to occur when the body temperature exceeds what temperature
39°C
Secondry drowning can occur up to how long after a near drowning?
72 hours, and is a hospital case.
After a water jet injury you should do what?
Seek arrange surgical examination as soon as possible.
maximum wave height is defined as the greatest wave height observed in a what period.
10 minute
Significant wave height is the average height of the largest …… ……. of all waves observed in a
10 minute period
One third
How many knots max for working on bottom construction sat diving
1.2 knots
How many knots max for mid water construction sat diving ?
1 knot
How many knots max for air diving mid water work observation air diving?
1 knot
How many knots max for light construction air diving on bottom?
1 knot
How many knots max for light construction on bottom sat diving?
1.5 knots
How many knots max for non routine observation air diving on bottom
1.5 knots
How many knots max for observation sat diving on bottom?
1.8 knots
How many knots max for non routine sat diving on bottom?
2 knots
The force exerted on a diver and his equipment by the current is proportional to the water velocity
squared.
If the velocity doubles, the force increases how many times?
four
Diving may also be stopped by whom apart from the dive supervisor ?
master of a vessel
The thermal boundary between layers, known as a …………..
thermocline
The velocity of sound in air is?
330 m per second
In water it is?
1,440 m per second
What is DMAC 12?
Diving in the vicinity of seismic operations
Sonar transmissions may have ……….-………… effects on the dive, causing disorientation
audio-vestibular
Recent incidents have demonstrated that significant adverse effects may be experienced
by divers at distances of up to how many km
27 km
Good practice is to notify relevant parties within ….. kilometers of a proposed sonar activity
45 kilometers
Within how many kilometers should a joint risk assessment should be conducted, between the clients/operators involved and the seismic and diving contractors in advance of any simultaneous operations?
30km
When simultaneous operations are conducted, the diving contractor should generate and submit a short online
Report of Simultaneous Seismic and Diving to DMAC
True or False?
True
Because of
the attenuating effects of the helmet, divers with helmets are safe from any known sonar transmissions
with frequencies above …..Hz.
500
A supervisor can pass over the total communications responsibility to anyone.
True of false
False.
Only to another qualified and appointed supervisor.
Communications:
Name OPEN dedicated lines from dive control.
Bridge & crane
What are the two other dedicated lines (not radio)
Sat control
ROV
Documentation:
What the are the 17 documents to be kept on a dive site?
1) Company operations manual.
2) Safety management system (SMS).
3) Management of change procedure.
4) Bridging document (interface document between clients’ and companies’ SMS).
5) Risk assessments.
6) In date system audit document.
7) Technical manuals.
8) Equipment on site.
9) Planned maintenance system.
10) Repair an maintenance reports.
11) Diving project plan.
12) Diving operations logbook.
13) Dive records sheets.
14) Pre and post dive checklists.
15) Use of equipment checklists.
16) Incident investigation documentation.
5 other regulating bodies documentation that may be on board?
National ACOP’s
IOGP
AODC & IMCA
IMO Code - DIving Sytems
IMO Guidelines Hyperbaric Evacuation
What is the individual documentation required?
Passport
Record of competence
Letter of appointment
Job description
Qualification certs
Medical Cert
Offshore survival cert
Who requires a log book?
Supervisors
Divers
Inspection divers
Life support techs
Dive techs
Diving tenders (record of training and assessment)
Minimum information to put into divers log book
1) Name of diver
2) Date
3) Address of company
4) Location / Vessel
5) Max depth
6) Left surface / Bottom time . Arrived surface
7) Time in deco chamber
8) Type of breathing apparatus used.
9) Work done tools used
10) Deco schedules
11) Illness or injury
12) Incidents or special notes
What is IMCA D0 11
Guidance on auditing of diving systems
What is MCA D0 18
Code of practice for the initial and periodic examination, testing and certification of diving plant and equipment
Verification of certification and the planned maintenance system should normally be carried out at least?
annually
What is IMCA Diving Equipment Systems Inspection Guidance Note (DESIGN)
audit document
There are currently DESIGN audit documents for air?
DO 23
What is the IMCA DESIGN audit documents for sat?
DO 24
What is the IMCA DESIGN audit documents for surface supplied mixed gas?
D0 37
What is the IMCA DESIGN audit documents for mobile/portable diving systems?
D0 40
What is the IMCA DESIGN audit documents for hyperbaric reception facility forming part of a hyperbaric evacuation system?
DO 53
What is RIDDOR in the UK?
Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013
What records need to be kept under RIDDOR?
Work related accidents that cause…
1) Death
2) Serious injury
3) Industrial diseases
4) Dangerous occurrences (near misses)
Do non work related accidents have to be reported to RIDDOR?
No
What is a non-conformance reports are report?
Occurrences which do not cause a near miss or other incident, but do not conform to laid down procedures or standards
Accidents and incidents should also be reported to the master of the vessel or offshore installation
manager (OIM)
True or False
True
Each team
should include how many personnel qualified in advanced first aid as a diver medic
At least one
Does the diver medic need to be a diver?
No. Only has to be able to be fit and competent to enter the chamber
If the diver medic IS a member of the dive team then how many diver medics do required.
At least one to be available on shift on surface.
The absolute minimum for a surface supplied air/nitrox diving operation under the IMCA international
code of practice for offshore diving is how many?
5
air diving supervisor;
working diver;
standby diver;
tender for working diver;
tender for standby diver.
The absolute minimum number of personnel required to carry out an offshore surface supplied mixed
gas dive is?
6
The absolute minimum team size to support divers during a closed bell diving operation and 24 hours’
life support operations under the IMCA international code of practice for offshore diving is?
9
closed bell diving supervisor
two life support supervisors;
two life support technicians;
two divers in the bell;
surface standby diver;
tender for surface standby diver.
In all cases, the precise arrangement, including responsibilities and chain of command, needs to be agreed
in writing.
True or False?
True
if a member of the diving team is asked to work for more than 12 hours, he needs to have had at
least …….. …….. off in the previous 24 hours
eight hours
The longest period a member of the diving team will be asked to work, and only in exceptional
circumstances, will be how many hours before being given eight hours of unbroken rest
16 hours
in saturation diving, bell runs will not last more than how many hours from seal to seal and the divers
must then have how many of unbroken rest
8 hours seal to seal
12 hours unbroken rest
no person will be expected to work for more than 12 hours without an intermediate meal break
taken away from their place of work
True of False?
True
Maximum pO2 supplied to the diver from the bail-out bottle should be
1.4 bar
minimum pO2 supplied to the diver from the bail-out bottle should be the
same as the pO2 in the diver’s primary breathing gas mixture, with an absolute minimum of PPo2 of….
0.4 bar.
IMCA D 035 is?
Guidance on selecting vessels of opportunity for diving projects
IMCA DO 15
Mobile/portable/daughtercraft surface supplied systems
What are 4 dive support locations?
Daughter craft.
Small air range DSV or supply boat.
Large Monohull or multihull DSV.
Fixed platform or temp platform
What is IMCA D10
Diving operations from vessels operating in dynamically positioned mode
What is IMCA M103
Guidelines for the design and operation of dynamically positioned vessels
DP system can be divided into what five sections
power, propulsion, control, reference and sensors
Name the 3 DP propulsion systems
Tunnel thruster
Azimuth thruster
Main engines
Name the 5 DP reference systems
Hydrocoustic
Laser
Radar
DGPS
Taut wire
Name 3 DP environmental sensors
Altitude
Movement
Environmental
What is a DP excursion
any change of position or heading, either intentional or unintentional. It can range from many meters to less than a meter.
During proving trials, the system is tested in all normal modes of operation and failure modes are
simulated.
True or False
True
Minimum DP trial time is ?
30 minutes
During trials how many modes of failure are simulated?
All modes ie:
DP 3 = 3 redundancies
On the basis of the trials, calculations of station keeping capability are made for various
situations, including the maximum number of thrusters and/or power units that could be operational
after the worst single failure
Ture or False
True
What is a polar plot form?
Data collected over time showing the capability V’s historically encountered environmental conditions.
A fully operational DP system should reliably keep a vessel in position in such a way that the maximum
excursion from vessel motions and position keeping will not be more than….
half the critical excursion for the work being carried out.
A critical excursion means…
an excursion where, because of the speed and/or extent of the movement,
personnel could be injured and/or substantial damage could be sustained
What is operational safe working limit?
These are environmental limits within which a critical excursion caused by a single fault is very unlikely.
(Either because there is adequate control and power remaining, or because the environmental loads are small)
IMO recommends that every DP vessel built after July 1994 should be assigned to an equipment class.
How many classes are there?
DP 1
DP 2
DP 3
What class is the minimum for diving?
DP 2
Define DP 1
Loss of position arising from a single fault
Define DP 2
Single point failure won’t cause loss of position ie: generator fail. But additional failure of a static component can cause loss of position
Define DP 3
Loss of position won’t occur from a single point failure including fire in one sub division or flooding of a compartment.
Define a green DP light
Normal operational status. Adequate equipment is on-line to meet the required
performance within the safe working limits;
Define a yellow
Degraded operational status. In general it is the condition where one or more items of
redundant DP equipment has failed, safe working limits are being exceeded or an excursion of
heading or position is likely but will not be critical
The minimum DP control requirement for diving
operations is
two automatic fully redundant control systems
There should also be what other manual control system?
joystick for manoeuvring, which can either be separate from or an integral part of the DP control system
Class 3 vessels should have an additional DP control room, in case the main control room is put out of action by fire or flood.
True or False?
True
For diving work at least …….. position references need to be on-line and at least two should
be of different types.
Three
Position references should have independent ……….. ………. and cable routes should be separate
power supplies
Name the 5 different DP position sensors
Taut wire
Hydroacoustic)
DGPS
Laser radar systems: FanBeam and CyScan
FM radar systems:
RADius and RadaScan.
HPS positioning in shallow water, the cone
is very narrow and it is possible for the vessel to miss the transponder signal and overshoot the position.
True or False?
True
If there is only one transducer on the vessel, the acoustic system can only count as one reference
system, regardless of the number of transponders on the seabed
True or False
True
Two major causes of problems with DGNSS are scintillation…
The effect of solar activity.
Shadowing of antenna by nearby structures
DP 3 should have a separate DP control room to serve as a back up.
True or False
True
How many position sensor have to be online for diving operations?
3 sensors
2 must be of different type
Different position references have to have what?
Independent power supply
Different cable routes
Name the 5 different DP position sensors
Tautwire
Hydroacoustic
DGPS
Laser
FM radar
Limitations of tautwire are?
Minumum depth req’d
Short excursions shallow
Affected by heavy swell
Potential hazard to divers
Limitation of Hydroacoustic Position Reference (HPR)?
Minimum depth req’d
Affected by thrusters, bubbles and water jetting.
Limitations of DGNSS?
Affected by solar flares and shadowing of receiver.
Limitations of laser positioning systems?
Affected by heavy rain, snow and fog.
Line of sight only.
Degraded performance by direct sun shine.
Target can’t be near reflective surface.
What’s the range of a Fan Beam laser radar?
<2000 meters
What’s the range of Cyslan laser radar?
<400 meters
Limitations of an Artemis system?
Line of sight
Low battery in fixed unit
Radar transmissions
Other DSV’s in area
Is an Artemis system safe to use in a ZONE ONE environment?
Yes. No explosion hazard.
What should Artemis not be using during?
Wire line operations
Explosive works
Name the 3 environmental sensors of a DP system
Anemometers
Gyro compass
Vertical reference systems
How many anemometers need to be on line in a DP system
Two.
In different locations and have separate cable routes
How many gyro compasses need to in a DP system?
At least 3
How many vertical reference systems does a DP system need to have ?
At least two. With different cable routes and power sources.
Communications:
Dive control needs to have direct comms (with back up) to whom?
DP control
ROV
Crane
Are DP joystick operations acceptable during diving ops ?
No
Can changes of heading and position are not made simultaneously?
No
What is the maxium single move allowed in DP with divers on seabed?
5m
Umbilical diver’s umbilical must be physically restrained to prevent it from coming within how many metres of a hazard?
Five meters
Bellman should be restrained to prevent it coming within how many metres of any identified hazard.
Three meters
Golden Gate Rules:
What are the 3 golden gate rules?
Which ever is lesser:
Distance from golden gate to diver must not exceed distance from bell to thruster - 5m
Distance from golden gate to diver must not exceed golden gate to thruster - 5m
And:
Distance from bell to golden gate must be 2m less than golden gate to diver.
Suppose the distance from the basket/bell to the thruster (Distance A) is 17m and from the in water tend point to the thruster (Distance D) is 20m. Calculate C.
The distance from the basket/bell to the in-water tend point (Distance B) is 8m
Because it is shorter than Distance D, Distance A (17m) is selected.
Distance C, therefore, must be between 10 and 12m.
Suppose the distance from the basket/bell to the thruster (Distance A) is 25m and from the in water tend point to the thruster (Distance D) is 20m. Calculate C
The distance from the basket/bell to the in-water tend point (Distance B) is 10m.
Because it is shorter than Distance A (25), Distance D (20m) is selected
Between 12 and 15m
Diving withing anchor patterns what over what horizontal distance does a mooring chain not require second means of confirmation?
250 meters
DPO is to monitor the moored vessel via ………. and ……… and diving operations are to be stopped immediately if contact is lost.
Radar and radio
Moored vessel is not to adjust ………. or ………. without first notifying the DPO
tension or draft
Ideally how much horizontal distance should be between a bell and mooring line or chain?
50 meters
If a bell is within 50 meters of a mooring line / chain what contingencies are in place?
Position of mooring line / chain actively monitored (ROV or beacon) and plotted.
Time within anchor pattern kept to a minimum
Provision of lost bell(s) considered during planning.
Risk assessments to cover touch down visibility and snagging
Gas handling rules:
Never operate a valve in a gas system without first checking with who?
LSS or Supervisor
Always ……….. a quad or kelly before connecting it
analise
Never put a gas on line to the panel without?
analysing it again
Never put gas online to the diver without an inline ……… with a …… and ……. alarm
Analyser
High
Low
Before connecting hoses always visually inspect them for what?
cracks in the fittings and that they are fit for use
Never use a flexible gas line without what?
A whip check
Open valves on bottles how?
Slowly, arms length, looking away, open all the way and back half a turn
Helium bottle cylinder is …….. colour on the body and ……. colour on the shoulder
Brown
Brown
Diving oxygen cylinder is …….. colour on the body and ……… colour on the shoulder
Black
White
Heliox cylinder is …….. colour on the body and …….. on the
Brown
Brown / White quarters
Nitrogen cylinder is ……….. colour on the body and ……… colour on the shoulder
Grey
Black
Argon cylinder is ……… on the body and ……….. on the shoulder
Dark blue
Dark blue
Breathing air cylinder is ………. on the body and ………. on the shoulder
Black
Black / White
Co2 cylinder is …………. on the body and ……… on the shoulder
Black
Grey
Calibration gas bottles are coloured?
Pink
Oxygen must never be
stored in a
confined space
oxygen analyser with an audio and visual hi-lo alarm should be placed in
the gas hold
The European standard for gas colour coding is?
EN1089
EN1089 does not require cylinder body to be coloured
True or false?
True.
Quarters or bands colour coded on neck only
According to DO43:
If cylinders in a quad are completely encapsulated, with no bottle shoulder showing then what denotes quad content?
20cm circular flag painted on each face in the appropriate colour code of the condense.
Quads may be stored below deck and should have provision for what ?
Fire fighting and o2 analysis of the atmosphere.
According to the DO43 bottles in a quad don’t have to be colour coded if the quad frame is painted in the appropriate colours for that gas.
True or False
True
Cylinders that go under water need to be tested how often according to DO18?
6 Monthly visual
2 yearly MWP + opt hdro
4 Yearly Hydro to 1.5 MWP.
Greater than what % is oxygen considered pure for safety reasons ?
25%
What is the maximum recommended line pressure for pure oxygen?
40 bar
Flexible hoses should be kept to a minimum for oxygen handling.
True or False
True
1/4 turn valves are allow in oxygen lines but only as emergency shut offs.
True or False
True
Over what % and pressure is not recommended that 1/4 values be used
25 percent
15 bar
DMAC 05 and IMCA DO14 recommend what as the minimum oxygen content for heliox from 50 to 150 meters?
2%
Can 100% He be used offshore in special and controlled circumstances ie: extremely deep sat?
Yes.
What is BSEN 12021
British compressed air purity standard
How much
CO, Co2, Oil under BSEN 12021
5 ppm
500 ppm
0.5 mg / m3
How much H2O under BESN12021?
LP comp
40 - 200 bar
200 + bar
LP = 25 mg/m3
40 to 200 bar = 50 mg/m3
200 + bar = 35 mg/m3
What fraction is the BSEN 12021 of the compressed air breathing standard
1/6 th 8 hour exposure limit for breathing compressed air.
Contaminates are less due to increased pressure
What DMAC doc deals with flying after diving?
DMAC 07
How long before you can fly after a no stop air dive in the previous 12 hours?
2 hours (600m)
8 hours (short haul)
24 hours (long haul)
How long before you can fly after air / nitrox / heliox surface supplied dive >4 hrs?
12 hours (600m)
24 hours (commercial)
How long until you can fly after a heliox saturation?
12 hours (600m)
24 hours (commercial)
How long until you can fly after a air / nitrox or trimix sat?
24 hours (600m)
48 hours (commercial)
How long before you can fly after a bend with immediate recompression and resolution after treatment?
24 hours (600m)
48 hours (Commercial)
LARS:
Man riding wire should be …… ……. and have a saftey factor of …… to …..
Non rotating
8 to 1
According to the DO50 what is the minimum gas requirements for surface supplied diving?
Sufficient gas for:
Two emergency dives of 30 minutes to working depth.
Pressurise to max treatment depth (50 msw) plus 3 full surface decompressions.
90 m3 medical oxygen
HP / HP + LP / LP + LP
What is the recommended max depth of SRU (SCUBA Replacement Units)
30 MSW
No Deco
What is the absolute max depth of SRU - with appropriate risk assessment?
50 MSW
No Deco
DO15 recommends SRU consists of a minimum of how many cylinders?
2 x 48 liter cylinders @ 150 bar
How far can the daughter craft operate from the DSV?
15 minutes
Line of sight
What other contingencies should be in place.
Means to transfer diver to DDC
Prop guards to protect diver
Second craft to assist if req’d
According to the DO23 a ladder can not be used as a primary egress if the diver has to climb more than how many meters above the water line?
Two meters
How far beneath the water line should the ladder extend?
Two meters
How much OBG should a wet bell have?
Enough pressure and volume to sustain the divers at depth and complete required decompression.
What provision is there for an unconscious diver?
Means to hold his head above water in the air space.
The wet bell to remain negatively buoyant when the dome is full of air.
True or False
True
Surface gas dives must only be conducted from a proper wet bell.
True or False
True
Maximum depth of a surface gas dive shouldn’t exceed ?
75 meters
> 50 msw in water deco shouldn’t exceed how long?
100 minutes
50 to 75 meters the bottom time shouldn’t exceed what?
30 minutes
What is the minimum team size for surface gas diving?
6
What is the minimum OBG requirements / diver for surface gas?
7 m3 heliox
7 m3 compressed air
Mixed Gas DDC should be what minimum size for single diver operations?
1.37m / 54’’
Mixed Gas DDC should be what minimum size for two diver operations?
1.5m / 60’’
What does 1.5m / 60’’ require?
A bunk 1800mm long
Means of environmental control
After what build date does a DDC need to be 1.5m / 60’’ ?
1 Jan 2015
How much treatment gas is required?
Sufficient for two therapeutic treatments
What other additional procedures are recommended?
Procedures and tables as contingency for deeper tables using heliox and deeper treatment depths should they be required.
After what depth should consideration be given to the stand by being in water?
<50m surface stand by
>50 in water stand by
Closed Bell:
What is the minimum sized team for closed bell operations?
1 Dive sup
2 LSS
2 LST
2 Divers
1 Intervention diver
1 Tender
—————-
NINE
—————-
What are the recommendations for sat divers work / rest periods?
6 hours in the water max
A break after 2 hours
8 hours seal to seal
12 hours uninterrupted rest.
what is the the diving project plan?
Consists of the company’s standard operating procedures together with
site or task specific procedures
What needs to be done in order for an extension beyond the 28 day recommended duration of a sat?
Written agreement of the company’s medical
adviser, the divers and the diving supervisors.
Bell:
AODC 009 recommends what be in the bell?
emergency waterproof checklist of all valves that
must be closed to ensure pressure integrity in the bell and all those valves that must be kept open.
A duplicate should be kept in dive control
Photographs of all internal and external bell valves should be available in dive control.
True or False?
True
What is the minimum OBG requirement for the bell?
30 minutes at a breathing rate of 40 litres
(1.5 ft3) per minute at the maximum depth of the diving operation
24 hours o2
What is the frequency of a bell emergency transponder?
37.5 kHz
A common manifold block for attachment of an emergency umbilical is internationally agreed.
True or False?
True
A lost bell can be located using a locator deployed from a surface vessel, a diver hand-held locator or a locator mounted in an ROV. The transponder and locators should be checked and tested regularly.
True or False
True
AODC 61 states what about bell drop weights?
No single component failure to allow release
Two stage release
Won’t release accidentally if bell is tilted - but still will release intentionally in such circumstances.
Pneumatic or hydraulic systems won’t actuate by pressure bell is subjected to.
AODC 0192 recommends that all worksites should carry up-to-date internal and external photographs
of the bell to provide information to those attempting to rescue the divers if the bell becomes lost or
stranded.
True or False
True
The bell handling system should allow what?
the bell to be locked off the chamber system, lowered safely through the splash zone without undue spinning or swinging and positioned accurately at working depth.
It should maintain the bell at working depth without undue movement and allow it to be recovered
safely to deck and locked onto the chamber system.
The main elements of the handling system are what?
A-frame or trolley and cursor
Winch, main cable and guide wires
Umbilical handling system
Heave compensation gear (if fitted)
Cross haul system (if fitted)
Secondary recovery systems.
Minimum gas for sat under IMCA DO50?
Enough for:
4 hours BIBs in chamber
Intended bell runs plus same in reserve (excl OBG)
Pressurise all chambers to depth twice
Full deco twice allowing for medlock runs, toilet flush and leaks
Enough o2 for metabolic consumption x 2
The ppO2 in the diver’s mix will normally be
in the range of 0.6-0.9 bar
The ppO2 in the chamber will normally be
about 0.4 bar
Chambers:
Minimum chamber size for chamber manufactured after 1 Jan 2015?
60 inches / 1.5m
Minimum chamber size 1 Diver mixed gas
54’’ / 1.37m
Minimum chamber size for 2 Diver mixed gas?
60’’ / 1.5m
What must a 60’’ / 1.5m in addition?
A bunk 1.8 long
Environmental control
What is the minimum diameter saturation chamber manufactured after 1 Jan 2015?
72’’ / 1.8m
What are the main classification societies for chambers
DNV
German Lloyds
Lloyds
ABS
Bureau Veritas
US Coast Guard
What is the minimum oxygen for combustion in a chamber?
6%
What is the minimum percentage for complete combustion in a chamber? (Flash fire)
16%
What is the USN fire zone calculation?
PPo2x33 / (o2% / 100) - 33
Chamber atmosphere is 0.48 ata PPo2. Minimum oxygen percentage for combustion what depth does the fire zone start?
231 fsw
What are the IMCA D050 requirements for an air chamber?
Enough gas for:
Maximum treatment depth (50m)
3 x surface deco’s
90 m3 therapeutic oxygen.
When not in use are air chamber BIB’s normally open or closed?
Closed
What is the maximum o2 % in a air chamber?
23%
sat BIB’s are to be online at all times and will have what mix online?
Bottom mix
Do BIB’s need to be oxygen cleaned?
Yes
Water supply is fed by a pump or a tanks pressurised with what HeO2%
2%
Can the potable water also be used for FiFi?
Yes
Chamber toilet mus have an ………… mechanism. There must be a ……. between the bowl and the seat. ……………. must be posted by toilet and peanut tank. During deco the holding thank must be …………. to prevent blow back.
interlocking
bowl
procedures
vented
interlock must
make it impossible to open the clamp if there is still pressure inside the lock, and
impossible to obtain a gas tight seal on the lock if the clamp is not properly closed
What is the service life of a view port?
10 years
Were must the certification be marked on a viewport?
Around its circumference
What is the DO50 gas requirements for saturation?
4 Hours BIB’s supply
Sufficient for treatments for the depths involved
Sufficient to pressurise to max depth, plus same again
Oxygen sufficient for metabolic consumption, plus what is required for deco - held in two separate banks
Plus sufficient gas to carry out intended bell run (or both bell runs if bottom turn around) Plus same in reserve.
OBG and Hyperbaric evacuation not included.
Hygiene: How often should bedding be changed out in sat?
Every 3 rd day.
Every day if there is an infection.
How often should preventative drops be used in saturation?
Every 8 hours
What are the parameters for saturation checked every hour?
Oxygen: 400mb *
CO2 : <5mb
N2 : 1 Bar *
Temp : 25 to 33 c
Depth: : + / - 0.3 msw / 1 fsw
- = not checked hourly
What is DMAC 28?
Provision of medical care for divers in saturation
What does the DMAC 28 recommend? (10 things)
Chamber at least 1.8m
Ability to make room for treatment bunk.
Treatment bunk waist height with access from at least one side.
Firm base to medical bunk with ability to tilt either end at 30 degrees.
Have a work surface for medical equipment
Means of suspending a drip
Convenient medical lock 300mm in diameter
Good comms close to causality
Suitable extra lighting
Sufficient additional hull and electrical penetrators for medical equipment.
What is a HES?
Hyperbaric Evacuation System
What 5 things does the HES include?
Hyperbaric evacuation procedures.
Means of evacuation
Reception facility
Contingency plans
Safe havens
How many hours should a HRU support life minimum?
72 hours
What are the two types of HRU?
SPHL
HRC
Phase 1: How many minutes should it take to transfer divers to the HRU maximum?
15 minutes
Phase 2:
How many minutes to launch & 100m clear maximum?
30 minutes
Phase 3: How long should it take to reach HRF ideally?
75% of endurance
72 hrs - 25% = 52 hours.
What is the safe haven?
Where the HRU arrives on completion of transit.
Either to HRF or transport to HFR
Phase four:
Complete safe decompression of the divers one of what two ways?
LSP to HRC in safe location
TUP from SPHL to HRF
Evacuation planning is risk assessed on what 5 points
Working depth / Storage depth
Prevailing weather and sea conditions
Distance and duration to safe haven
HRC or SPHL
Anticipated medical treatments required
How many ‘Diver Rescue’ markings should there be on a SPHL / HRC
Three
One on each side
One on top
What 6 instructions should be visible?
Towing arrangements
All external connections
Gross weight in air
Lifting points
Name of parent ship
Emergency contacts
What 5 things should be written on the warning sign?
Don’t touch valves
Don’t get occupants out
Don’t make connections
Don’t give food, water, meds
Don’t open hatches
How often should the SPHL / HRC be deployed / float tested
Once every 6 months
Wire Ropes:
What is the general safety factor on a working wire rope?
5 to 1
What is the safety factor for a man riding wire rope?
8 to 1
Multi-legged slings should ideally be used with the legs at less than ….° to each other and never with the
legs at more than …..°.
90°
120°
The SWL with legs between 90° and 120° is about …. of the SWL with the legs
at less than 90°.
0.7
What is the maximum fleet angel of a winch wire?
1.5°
There must be at least 38 m of lead for every metre of fleet.
The drum should not be overloaded with cable. Normally there should be about …… times the
diameter of the winch wire between the outside of the top layer of the wire and the edge of the
drum flange
2.5 times
Lift bags:
What are the two uses of lift bags?
Static ‘sky hook’
Dynamic ‘lift & shift’
A bag should be labeled with what in addition to it’s rating?
Unique serial number
A bag should not be used if its components have been modified or replaced unless approved my manufacturer.
True or False
True
No more that …… ft of slack should be in an inverter line of an inflated lift bag.
One foot
Before use the bag(s) serial numbers should be checked against the certification package.
True or False
True
What other 4 things need to be checked?
Certification period
Components of bag
Operation of dump
Inverter line attachment point and rating of line.
Oxy-Arc cutting:
What is the maximum recommended amps for broco?
150 amps
What is the polarity of a broco torch?
Negative
How can you test this in the water?
Hydrogen bubbles from electrolysis migrate from tip to job.
Earth should be as close as practical to job.
True of False
True.
Power tools:
All power tools need to have what?
A dead man handle
SPHL / HRC Markings:
How many sides does an SPHL / HRC need to be marked on?
Three.
Each side and top.
What are the required dimensions of the signage?
1200 / 450 minimum
What height are the words ‘Diver Rescue’ to be?
150mm high
What size does the ‘Call rescue services and keep in sight’ need to be?
50mm
And the yellow diver helmet?
300 mm high
What are the six instructions that must be visible above the water line?
Towing arrangement
External connections
Gross weight
Lifting points
Name of ship & rego.
Emergency contacts
What are the 5 warning instructions?
Don’t touch valves
Don’t get occupants out
Don’t make connections
Do not feed the animals
Do not open hatches
Hyperbaric life boats need to be wet tested every?
6 months
Bell Drills:
How often do IMCA recommend unconscious diver recovery drills?
Withing first 3 bell runs and every two weeks there after.
