Occupational Health and Safety Act, 1993 (Act No. 85 of 1993)Code of PracticeDiving Regulations, 2009Code of Practice for Inshore Diving5. Diving Equipment5.2 Diving equipment |
Diving contractors working under the scope of this code must use surface supplied diving equipment whenever reasonably practicable, and only use scuba or airline equipment when conventional surface supplied equipment is not practicable, or there is a significant logistical advantage and the HIRA indicates that there is no significant additional risk.
No diver may undertake a dive to a depth greater than that for which the equipment he or she is using is suitable. Suitability of equipment for purpose should be confirmed by the manufacturer. This is usually specified in the user manual for the equipment. All equipment used for a dive must be
suitable for the planned depth.
| 5.2.1 | Surface-supplied diving equipment (SSDE) |
Surface-supplied diving equipment includes as a minimum:
| • | a full-face mask or helmet |
| • | a diver's umbilical |
| • | a bail-out system, connected to the primary breathing apparatus by a valve operable by the diver, |
| • | a full body diver safety harness, |
| • | an voice communication system between the diver and the control point, |
| • | a surface breathing gas control panel, |
| • | a suitable pressurised breathing mixture supply |
| 5.2.1.1 | Diving masks and Helmets |
A full-face mask or diving helmet is an essential component of surface supplied diving equipment.
Helmets and full face masks may be supplied with breathing gas by a demand or free-flow system.
| 5.2.1.2 | Diver's umbilicals |
The required length of the diver's umbilical in relation to the worksite will need to be included in the dive plan, particularly where an emergency situation might require rapid location and recovery of the diver.
The standby diver's umbilical must be at least 2m longer than the working diver's umbilical.
The length of the umbilical should take into account the distance to hazards.
A diver's umbilical must comply with the following minimum requirements:
| • | Contain a breathing gas hose of non-toxic composition (suitable for breathing gas) and a minimum internal diameter of 9mm and a working pressure of 350 kPa (35 bar) |
| • | Contain a pneumofathometer hose of nontoxic composition and a minimum internal diameter of 6mm |
| • | Contain a hardwire communications cable for voice communications |
| • | Have a strength of at least 5 kN |
The diver's umbilical must be connected to the diver's safety harness by means of a screw gate caribiner to prevent the umbilical pulling on the diver's helmet or full-face mask.
| 5.2.1.3 | Bailout systems |
A bailout system is an independent supply of a breathing mixture that is carried and activated by the diver.
An adequate bailout system must be worn by all divers and the breathing mixture in the bailout system must be appropriate for the dive.
The bailout system capacity must be sufficient to allow the diver to reach a place of safety in emergency situations (e.g. for the time needed by the standby diver to reach the submerged diver and for both to return to the surface; or to return to the stage or wet bell, if this is being used in the diving operation).
| 5.2.1.4 | Safety harness |
A diver's safety harness must be:
| • | capable of supporting the weight of the fully dressed diver in air. |
| • | attached to the diver in such a way that it cannot be accidentally unfastened. |
| • | adjustable to comfortably fit the diver. |
| • | provided with an attachment point for lifting the diver in a posture which will minimise potential injury to an unconscious diver during lifting. |
| • | provided with an attachment point for connecting the umbilical in such a way that loads will not be transmitted to the mask or helmet. |
Other features such as support for the bailout system, ballast weights, tool pockets and clips, and adjustable buoyancy are optional.
| 5.2.1.5 | Voice communications system |
See section 8.2.9
| 5.2.1.6 | Surface control panel |
The surface gas control panel has the following functions:
| • | provide an adequate flow of primary breathing gas to each diver through the primary umbilical hose at the appropriate pressure, |
| • | provide an alternative supply of primary breathing gas to each diver through the pneumofathometer hose when required, |
| • | Indicate the breathing gas supply pressure, |
| • | indicate the depth of each diver by measuring the pressure in the pneumofathometer hose, to a resolution of 0.5msw, |
| • | provide an adequate flow of backup breathing gas to each diver through the primary and pneumofathometer hoses, |
| • | Switch between primary and backup breathing gas supplies without noticeably interrupting supply to the divers |
| • | Prevent breathing gas loss from each diver on the panel if any hose to another diver is cut |
| • | All valves and gauges must be labelled to indicate function and, where appropriate, which diver they serve. |
| • | If gases other than air are to be supplied to the diver, an oxygen analyser must be supplied from to the supply manifold. |
| 5.2.2 | Self-contained diving equipment (SCUBA) |
Scuba is a non-preferred option for diving under this code, however there may be occasions when the use of scuba may be justified by logistical constraints and a HIRA that indicates acceptable risk under the specified circumstances.
Two classes of scuba exist: Open circuit, where a the breathing gas is lost to the environment on exhalation, and Rebreather systems, where all or part of the exhaled gas is retained in the breathing circuit, carbon dioxide is removed, and oxygen added before the gas is made available for breathing again.
Open circuit systems have the disadvantage of limited gas endurance, but are more robust and have fewer critical failure modes than rebreather systems.
Rebreather systems can provide considerably longer gas endurance for an equivalent gas supply, and minimise the amount of gas released as bubbles, but have an inherently greater risk of failure while in use, even when correctly maintained and checked before use. It is possible, but unlikely that a rebreather would be acceptable for any diving operation under this code, and any contractor considering their use should ensure a particularly rigorous risk assessment for the equipment, and is strongly advised to ensure that this is done by an expert.
Open Circuit scuba may be used with either a full-face mask or a half mask and demand valve. A full-face mask allows voice communications equipment to be used and is the preferred option under this code. Most full face masks allow a bailout system to be connected to the mask in such a way that the diver can change from primary to bailout gas without removing the mask. The switchover system must allow the diver to easily check which supply is in use at any time, and to monitor the remaining gas pressure in both supplies. A large range of configurations are possible, and the contractor is responsible for ensuring that the system chosen is fit for purpose.
Scuba equipment under this code includes at minimum the following:
| • | Primary breathing air supply from high pressure cylinder/s carried by the diver on a harness, including regulator with demand valve and accurate and legible pressure monitoring gauge. |
| • | Buoyancy compensator device capable of providing the diver with neutral and positive buoyancy without the need to jettison weights or other diving equipment. The BCD is not required or expected to support heavy tools or equipment. |
| • | Full-face mask, or if not appropriate, half mask. |
| • | Bailout system as specified in section 5.2.1.3 comprising independent gas supply carried by the diver and demand regulator, with means of changeover and pressure monitoring gauge. |
| • | A diver's safety harness as specified in section 5.2.1.4 |
| • | Lifeline as specified in section 5.4.1 |
| • | Cutting tool suitable for clearing entanglement by rope or line. |
| • | A means of monitoring depth. |
A personal dive computer or recording bottom timer is strongly recommended for all dives in open water.
5.2.3 Airline diving equipment
Airline (also known as Hookah) is a non-preferred option for diving under this code, however there may be occasions when the use of airline may be justified by logistical constraints, and a HIRA that indicates acceptable risk under the specified circumstances.
Airline is customarily used for shallow water aquaculture and harvesting operations, and has a satisfactory safety record in these applications.
Airline may be used by Class IV divers with a suitable training endorsement.
Airline equipment under this code includes at minimum the following:
| • | Airline supply hose with minimum inside diameter of 9mm suitable for breathing gas, complete with demand regulator system, attached to the safety harness by a screw-gate caribiner, in such a way that loads are not transmitted to the mask or DV from the airline or lifeline. |
| • | Airline supply hose is usually buoyant when filled with air at working pressure. Neutrally buoyant or negatively buoyant airline may be considered in special circumstances. |
| • | Lifeline as specified in section 5.4.1 strapped to the airline if the airline is not suitable for this purpose alone. |
| • | Primary air supply from low pressure breathing air compressor or regulated flow from high pressure cylinders. |
| • | A loss of pressure in the airline must not allow air to flow back into the line from the mask or demand valve, or from the bailout system. |
| • | A loss of pressure in the airline must not compromise the breathing gas supply to any other diver |
| • | Full-face mask, or if not appropriate, half mask. |
| • | Bailout system as specified in section 5.2.1.3 comprising independent gas supply carried by the diver and demand regulator, with means of changeover and pressure monitoring. |
| • | A diver's safety harness as specified in section 5.2.1.4. |