scuba Flashcards
Planned exceptional exposure dives shall not be conducted except by specific authorization from whom?
Chief of Naval Operations (N97)
Diving supervisors should consider employing an independent back-up air source for dives exceeding what depth?
100fsw
What is the Maximum depth for standby SCUBA diver using a fully charged single cylinder with less than 100 SCF air available?
60fsw
What is the normal and maximum working limit for SCUBA diving operations?
Normal: 130fsw
Maximum: 190fsw
SCUBA diving operations deeper than 130fsw may be made with approval of whom?
The Commanding Officer or Officer-in-Charge
Who can approve SCUBA decompression dives?
Commanding Officer or Officer-in-Charge
Who designates officers as Officers-in-Charge?
By BUPERS order
Officers not designated by BUPERS as OICs are serving under the authority of the Commanding Officer and may not exceed depth or no decompression limits without specific authority delegated from whom?
The Commanding Officer
What are the restrictions of USN civilians conducting SCUBA dives?
Depths deeper than 100fsw or outside no-decompression, requires a recompression chamber that is available within 5 minutes of the dive location.
Cylinder manifold must be equipped with a manual reserve (J valve), or an independent reserve cylinder gas supply with a separate regulator.
A submersible pressure gauge must be worn by each diver.
What governs the USN civilian SCUBA diving restrictions?
29 CFR Part 1910
How long shall USN Civilian divers remain at the location of the recompression chamber after surfacing for all dives that require a recompression chamber to be available within 5 minutes of the dive location?
1 Hour
What is the minimum equipment to conduct SCUBA diving operations?
Open-circuit SCUBA with J-valve or submersible pressure gauge Life preserver/buoyancy compensator Weight belt (if required) Dive knife Face mask Swim fins Submersible wrist watch Depth gauge Submersible Pressure Gauge
What are the principle applications of SCUBA?
Shallow water search
Inspection
Light repair and recovery
What are the advantages of SCUBA?
Rapid deployment Portability Minimum support requirements Excellent horizontal and vertical mobility Minimum bottom disturbances
What are the disadvantages of SCUBA?
Limited endurance (depth and duration)
Limited physical protection
Influenced by current
Lack of voice communication (unless equipped with a through-water communications system or full face mask)
Standby diver must have a minimum of how many SCF of air for dives deeper than 60fsw?
100scf
What is maximum current to conduct SCUBA diving operations?
1 knot
What is required to conduct SCUBA diving operations in currents greater than 1 knot?
ORM analysis; at a minimum the divers(s) must be tended or have a witness float.
What is mandatory for diver recovery during open-ocean diving when diving off of a large platform or when the diver is untended and may be displaced from dive site?
Small Craft
What is the required number of personnel required for a SCUBA dive with a single diver?
4 personnel: Supervisor, Diver, Dive Tender, Standby Diver
What is the required number or personnel required for a SCUBA dive with a buddy pair?
4 personnel: Supervisor, (2) Divers, Standby Diver
What can a diving supervisor additionally act as on a SCUBA dive side?
Logs Standby Diver (if deployed)
What may the diving supervisor utilize as manning based upon operation necessity?
3 qualified divers and one non-diver tender
What is the single greatest safety practice in Navy SCUBA operations?
The use of the buddy system
Never leave a dive partner unless under what circumstances?
The partner has become trapped or entangled and cannot be freed without additional assistance.
When may a SCUBA standby diver remove the tanks?
At the discretion of the Diving Supervisor if the hazards of remaining dressed outweigh the need to have standby immediately ready to deploy.
What equipment shall the SCUBA standby diver be equipped with?
Need not be equipped with the same equipment as the primary diver, but shall have equivalent depth and operational capabilities.
Can you use non-divers as tenders on a SCUBA dive-side?
Yes; the Dive Supervisor shall ensure they are thoroughly instructed in their required duties.
How often shall tenders signal the divers with a single line-pull?
Every 2 to 3 minutes
If the divers fail to respond to line-pull signals, what action must be taken immediately?
The standby diver must investigate immediately
What are the 4 basic open-circuit SCUBA components?
Demand Regulator Assembly
One or more air cylinders
Cylinder valve and manifold assembly
Backpack or harness
What is the central component of the open circuit system?
Demand Regulator Assembly
The first stage regulator reduces high-pressure air from the cylinder to an intermediate pressure, also called what?
Over-bottom pressure
What is the principle disadvantage of the single-hose units?
Increased disadvantages of the single-hose unit
Exhaust of air in front of the diver’s mask
What is required when using an AMU approved full-face mask for SCUBA diving operations?
Approved single-hose first-stage regulator with an octopus
What is the depth limitation in SCUBA when using an approved full-face mask?
Maximum approved depth of the regulator
What is the required length and markings of a SCUBA octopus?
Length and designation markings are at the discretion of the diving unit
When is an octopus required?
Standby Diver
Diving with a full-face mask
Ice Diving
What is the preferred method of buddy breathing during SCUBA diving operations?
Buddy breathing with an octopus
What is the most common length of SCUBA intermediate hoses?
2 to 3 feet
When diving without a reserve, the dive shall be terminated when the cylinder pressure reaches what psi?
500 psi for a single cylinder or 250 psi for twin manifold cylinders
What specifications must all seamless steel or aluminum cylinders meet in order to be approved for use in the Navy?
Department of Transportation (DOT) specifications
The volume of a cylinder, expressed in actual cubic feet or cubic inches, is a measurement of what?
Internal volume of the cylinder