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This comment draft has been left in the format in which it was
written during 1989-1992. The 1998 ASF council has directed that
this code be distributed to all Corporate Members for comment
during 1998.
| 1.1.1 | The use of breath-held free diving techniques to pass through (sumps) or into (syphons) water-filled passages that do not have vertical access to an air surface overhead. |
| 1.1.2 | Cave diving using SCUBA or other supplied breathing apparatus is covered in a separate code, 'ASF Cave Diving Code of Practice'. |
| 2.1.1 | Every free diver must use a line in accordance with Section 3 of this Code. |
| 2.1.2 | Caution must be exercised in the event of higher than normal water level, as a dive may become considerably longer than expected or the line may end before an air space is reached. |
| 2.2.1 | Air trapped in roof pockets should not be breathed or relied upon (see 2.2.2 and 2.2.3). |
| 2.2.2 | Air trapped in roof pockets can be at higher than surface pressures. If this air is breathed and held during ascent, the free diver risks barotrauma of the respiratory system. |
| 2.2.3 | Again, air trapped in roof pockets may be foul air. |
| 2.3.1 | Hyperventilation, to increase the free diver's breath holding capacity, is discouraged. The risk of drowning if the free diver were to black out from this practice is much greater in this environment. |
| 2.4.1 | The intending free diver must be prepared to encounter zero visibility when contemplating such a dive, even if the water at first appears clear. |
| 2.5.1 | The use of equipment to aid a free dive into an underwater passage should be considered if practical (see Section 4). |
| 2.5.2 | Hooks, opening clips or karabiners without screw-gates must not be used to attach equipment to the free diver as they increase the risk of entanglement. |
| 3.1.1 | Lines, whether permanently fixed or temporary, may be floating or non-floating. However, they must have a breaking strain exceeding 500 kg. |
| 3.1.2 | Some cave environments will require a more substantial line, which must be used accordingly and/or replaced more frequently. |
| 3.1.3 | Lines used by cave divers are usually lighter and should be replaced with one of an appropriate strength. |
| 3.2.1 | Only one fixed line should be used or left through any water-filled passage (see also 3.2.2). |
| 3.2.2 | In the case of a divided passage where both sections are negotiable, then a second line, well separated from the first line leading from the closest air space, is preferred rather than to use an underwater junction in the lines. |
| 3.2.3 | Any line must be firmly secured at each end above normal water level and well clear of any overhead projections. |
| 3.2.4 | Any intermediate tie-off that is used to avoid the line pulling into narrow restrictions must be easy to negotiate so as to avoid loss of direction or entanglement in zero visibility conditions. |
| 3.2.5 | Under no circumstances is a free end of line to be left unsecured. |
| 3.3.1 | Free diving into unknown sumps and/or sumps with no fixed lines must be done with a continuous line from the free diver leading back to the start of the dive. |
| 3.3.2 | A line can be laid by a free diver using a reel or it can be paid out by a surface party. Using either method, the line or reel must be made secure to the diver. |
| 4.1.1 | Lights must be of a type to be reliable in operation when submerged, preferably waterproof to the intended depth of the dive. |
| 4.1.2 | A second source of light should also be carried by free divers. |
| 4.2.1 | A mask is considered to be a beneficial aid - unless the free diver is reasonably experienced, a mask should be used for cave diving. |
| 4.2.2 | Goggles should only be used in the place of a mask for very shallow ducks or dives, as the diver cannot fully compensate for the change of pressure that occurs with increased depth. |
| 4.2.3 | A snorkel should not be used or attached to the face mask strap for free diving. It may have an application for moving along water-filled passage only where there is overhead air space. |
| 4.3.1 | Fins are also considered to be a beneficial aid as they increase the diver's stability and propulsion whilst underwater. They may be omitted for short and/or restrictive free dives. |
| 4.4.1 | Wetsuits can also be used to provide insulation to reduce body heat loss when immersed in water (see also 4.4.2). |
| 4.4.2 | A weight belt should be considered if using a wetsuit (or other buoyant device), so that the diver can maintain neutral buoyancy for the dive - this is especially important if full wetsuits are used. |
| 4.5.1 | Dry or semi-dry suits may be used in place of a wetsuit, as in 4.4.1. |
| 5.1.1 | A method of signalling the next diver should be determined if a party of cavers is to pass through a sump. | ||||||
| 5.1.2 | If no other signalling method is to be used, the following line signals should be adopted:
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| 5.2.1 | If paying a line out to a free diver, the following signals are to be used in addition to 5.1.2:
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| 6.1.1 | Free diving is a potentially dangerous activity and must be treated with respect. | ||||||||
| 6.1.2 | Consideration must be given to a call-out procedure to properly trained and equipped cave divers in the event that overdue free divers do not return or are trapped by increased water levels. | ||||||||
| 6.2.1 | No person should attempt to free dive in a cave unless reasonably competent in water with another water-related activity or sport eg. snorkel diving, surfing, etc. | ||||||||
| 6.3.1 | If a person has no previous free diving in caves experience, then a training program should precede their first dive (see 6.3.2). | ||||||||
| 6.3.2 | The following should be handled with ease before considering your first free dive into a cave:
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| 6.4.1 | Consider the experience or inexperience of others if in a caving party about to attempt a free dive. | ||||||||
| 6.4.2 | Remember, a clear sump will silt when the water is disturbed eg. by a free diver entering or moving through the water. This will make a return or a subsequent free diver's pass much more difficult. |
© 1988-1998 Australian Speleological Federation