SABA MOD1 limits
Maximum Working Depth 30 m
Minimum Bailout Pressure 190 bar
Maximum Cylinder Pressure 232 bar
Main Cylinder Abort Pressure 60 bar
Diver Through Water Communications Up to 1000 m
When will Cylinder Pressure Sensor activate on main cylinder?
Approx 55 Bar and stops below 15 Bar
When will Cylinder Pressure Sensor activate on bailout cylinder?
170 Bar
Pre dive procedure for standby diver
a. Once dressed the standby diver may conduct a test dive at the supervisor’s discretion.
b. In order to conserve the air in the set, the test dive is to be conducted quickly and safely to a maximum of 5 metres, for a maximum of 5 minutes.
c. On completion of the test dive, the standby diver is to ensure that the BCA is fully deflated, weights inserted, and all ancillary equipment are correct.
d. The standby diver is to report the state of the set, pressures and equipment to the supervisor prior to any dive commencing.
SABA MOD 1 HMV limits
depth/ bailout pressure/c ylinder pressure/ main cylinder abort
Maximum Working Depth 30 m
Minimum Bailout Pressure 190 bar
Maximum Cylinder Pressure 232 bar
Main Cylinder Abort pressure 60 bar
Dive safety boat contents
a. Engine, enough fuel, fuel leads and tool kit.
b. Paddles/Oars;
c. DTWC (if required);
d. Signal Set Diver Supervisor Mk 2 (SSDS Mk 2);
e. Oxygen resuscitator (means of delivering 100% O2) and MESODO;
f. Method of recording the dive time as appropriate;
g. Copy of relevant diving tables;
h. Lost Diver Marker (LDM);
i. Flag Alpha - that can be clearly displayed;
j. Hand-held VHF IMM radio;
k. Depth sounding line or digital depth sounder;
l. At night, appropriate lighting in accordance with International Regulations for the
Prevention of Collision at Sea;
m. Boat bag and contents;
n. Where minimum personnel/equipment are utilised, a Jason’s Cradle can be included in the boat’s contents
o. A method of securing a diving set to the side of the dive boat;
Methods of decompression?
Air
JSP286 pt 2 vol 2
In water
In a compression chamber on the surface
Definitions
Ascent rate
Air
JSP286 pt 2 vol 2
1m every 4 seconds
definitions
Descent rate
Air
JSP286 pt 2 vol 2
1m every 2 seconds
definitions
repetitive dive (Air)
Air
JSP286 pt 2 vol 2
When a diver carries out more than a single dive, the time, depth and surface interval will determine combined dive rules
definitions
single dive (Air)
Air
JSP286 pt 2 vol 2
A dive started after a surface interval of at least 6 hours if the previous dive was at a depth of or shallower than 42m, or after a surface interval of 12 hours if the dive was deeper than 42m.
definitions
Transfer time (Air)
Air
JSP286 pt 2 vol 2
Surface Decompression - The total time from the diver leaving bottom or the last completed or partially omitted stop to attaining a pre determined depth in the compression chamber.
definitions
combined dive
Air
JSP286 pt 2 vol 2
A series of dives where any two consecutive dives have a surface interval less than either 6 hours shallower than 42m or 12 hours greater than 42m
definitions
bottom time
Air
JSP286 pt 2 vol 2
(duration of a dive) The total elapsed time from the diver leaving the surface to the diver beginning to ascend.
definitions
Total time of decompression
Air
JSP286 pt 2 vol 2
The total elapsed time from the diver leaving the bottom to reaching the surface after completing the decompression schedule.
In the surface decompression scenario - this is the elapsed time from the diver leaving the bottom (seabed) to arriving at the surface in the chamber after completing the decompression schedule.
control of attended divers ascent
Air
JSP286 pt 2 vol 2
- Lazy shot is clipped to shot rope/ Sonar marker and mine recovery outfit
- It is then lowered to 3m in excess of the divers first planned stop
- when diver is called up with 4 pulls, the diver responds with 1 pull to indicate when they have left bottom (attendant shouts diver left bottom - diver travelling)
- on reaching lazy shot diver gives 1 pull
- Lazy shot then raised to correct depth for first stop (diver keeping lazy shot at chest height)
Diving at altitude
Air
JSP286 pt 2 vol 2 (0507)
- If a dive is carried out at alititude the surface pressure is less than 1 Bar. Therefore decompression schedules need to be adjusted to prevent the onset of DCI
Following adjustments made
- dives between 100m-300m = add 0.25 of the depth to give depth of dive
- dives between 300m-2000m = add 0.3 of the depth to give depth of the dive
- dives between 2000m-3000m = add 0.5 of the depth to give depth of the dive.
Land journeys/ flying over 300m altitude post diving
JSP286 pt 2 vol 2 (0507 d.)
Air
If diving is to be followed by a land journey traversing heights in excess of 300m above sea level or flying at altitudes of above 300m above sea level and no alternative route can be taken then one of the following precautions is to be taken:
- adjust the decompression schedule iaw diving at altitude tables
- where this cannot be done adhere to flying after diving rules
Flying after diving
JSP286 pt 2 vol 2 (0508)
Air
Where possible it is inadvisible to travel by air (over 300m) less than 24hrs after diving.
Below are minimum time intervals between diving and flying
Air (no stops)
- no restriction up to 300m
- wait 2 hours to be able to go up to 1500m
- wait 4 hours to be able to go up to unlimited altitude (commercial)
Air requiring stops
- wait 2 hours to be able to go up to 300m
- wait 8 hours to be ablt to go up to 1500m
- wait 12 hours to be able to go up to unlimited altitude (commercial)
What is omitted decompression?
Omitted decompression. When a diver has surfaced without completing the necessary in-water stops, action must be taken to prevent decompression illness in
accordance with JSP 286 Part 2 Volume 2 for Air or JSP 286 Part 2 Volume 3 for Mixed Gas
Diving.
What is surface decompression?
Surface decompression is employed when it is necessary for a
diver or divers to carry out stops and it is either undesirable or impracticable for this to
be done in the water. An attended diver is given the signal, four pulls followed by two
bells - Come up, surface decompression.
Requirements for surface decompression (Air)
(1) Table 14-Mod and Table 15-Mod are to be used as detailed in Paragraphs
0520 and 0521.
(2) A compression chamber with a 6 bar (50 m) capability is on-site at the scene
of diving operations.
Requirements for surface decompression (Mixed gas)
(1) Oxygen-in-helium diving. Table 91 is to be used as detailed in Paragraph
20.
(2) A compression chamber with a 6 bar (50 m) capability is ‘on-site’ at the
scene of diving operations
