User:Pbsouthwood/Diving safety - Alternative approaches

Diving Safety - Alternative approaches

(This will eventually be part of an article titled Diving safety)

Responsibility and duty of care

Splits diving into Occupational and Recreational

• Occupational diving includes all diving where the diver is under the control or instruction os a third party, who is responsible for safety of the diving operation and has a duty of care to the diver, whether there is remuneration involved or not. Occupational divers are responsible for the safety of other involved personnel as specified in the terms of their occupation. This may include statutory and regulatory constraints, terms of employment etc. Typically (except in the case of scientific divers) the occupational diver is under some direct pressure to perform, but usually has some discretion in accepting to dive in the prevailing conditions.
  • Commercial diving
    • Off Shore Diving
    • Inland / onshore diving
    • HAZMAT diving
    • Nuclear diving
  • Military diving
    • Combat Diving
    • Clearance Diving
    • Fleet Diving
  • Public safety diving
    • Fire Department Diving
    • Law Enforcement Diving
  • Scientific diving when done under the auspices of a scientific organization.
    • Governmental Science Diving
    • Academic Diving
    • Aquaria Diving
  • Recreational diving instruction, whether for reward or not (responsible for safety of learners with minimums, at least, defined by the certification agency)
  • Media diving
    • Film and Video production diving
    • News
  • Guidance and safety monitoring of recreational divers, whether for reward or not (responsible for safety of the customers)
• Non-occupational Diving - Recreational/Technical divers are responsible for their own safety and to an extent limited and set out by prior agreement, for the safety of other members of the team.
  • Recreational diving is all diving that is done where safety and duty of care is the sole responsibility of the dive team, and the diver is a free agent, without responsibility to other members of the team except as freely chosen in that context
  • Technical diving by teams with surface crew is included, provided that there is no hierarchy of control which overrides the diver's options.

Approaches to diving safety

Self-sufficiency in reasonably foreseeable circumstances

See also: Solo diving

Self sufficiency has the advantage of simplicity, and lower risk of confusion due to inadequate communication. In circumstances where it may be physically difficult or impossible for another diver to provide assistance this may be the best option practicable. The major disadvantages are the lack of a second point of view, and the unmitigatable risks of loss of consciousness of a solo diver.

Buddy system - relying on a diver of similar competence

Main article: Buddy diving

Team of three divers - redundancy in buddy system

A third team member in the water complicates team co-ordination to some extent, but in conditions where complex action may be needed to safely recover from a reasonably foreseeable emergency, an extra team member can reduce task loading on the team and increase the chances of a successful outcome. Adequate training and thorough familiarity with the equipment, skills and procedures of the team and the details of the dive and contingency plans is necessary to reduce the risk of confusion due to the extra team member.

DIR vs other recreational and technical approaches

See also: Doing It Right (scuba diving)

The DIR movement (Doing it Right) and their philosphical offshoots prescribe an integrated system of equipment configuration and procedures which they promote as the optimum system for technical and recreational diver safety. This opinion is disputed to a greater or lesser extent by the rest of the recreational and technical diving community. DIR has a good record of safety considering the extreme diving environments that it has been used in, but there does not appear to be statistical evidence supporting their claims that the system is optimal.

Stand-by diver

See also: Surface supplied diving § Stand-by diver

A stand-by diver on short notice to enter the water, who is rested and in good physical condition, and is suitably competent to effect a rescue in the reasonably foreseeable emergencies associated with a planned dive, allows the dive team to initiate rescue efforts immediately, with a reasonable expectation of success.

Surface monitoring with communications

Communications between diver and surface control allows more effective monitoring of the whereabouts and condition of the diver. Voice communications with normally active diver to surface transmission allows near continuous monitoring of the diver by listening to breathing sounds.

Surface supplied breathing gas and physical connection to surface control point

Breathing gas supply is not limited by the diver's ability to carry the stored gas, and the continuous connection of the umbilical makes it relatively easy for the rescue (standby) diver to reach the working diver at short notice in an emergency.

Saturation diving

Saturation diving is a strategy to improve diver safety by limiting the number of relatively high risk decompressions for a given productive bottom time by storing the diver at a pressure roughly equivalent to the working depth over a period and decompressing very conservatively at the end of the exposure.

The balance of risk of heath hazards due to prolonged pressurisation versus multiple decompressions is considered to be advantageous, and the saving of time makes saturation diving acceptable and cost effective for projects where the cost and value of diver intervention is very high.

Factors affecting safety

Human factors

• People
• Organisations

Technology

• Equipment
• Diving mode
  • Scuba open and closed circuit
  • Surface supplied: Demand and free-flow helmet, Full-face mask, Gas, Surface decompression, Bell bounce.
  • Saturation
  • Atmospheric diving suit
  • ROV and AUV

Interface between human and technological factors

• Procedures
  • Training
  • Supervision
  • Operations

Procedural aspects

HIRA

• Hazard Identification and Risk Assessment
  • Used formally by professional divers, Informally by recreational and tech divers during dive planning and pre-dive briefings
• Risk reduction - Elimination, engineering, procedures, PPE etc
• Mitigation of consequences
  • Contingency planning
  • Emergency planning, evacuation procedures.

Accidents

Near misses

Most near misses not reported. Probable numbers relatively high compared to reported incidents.

Fatalities

See also: Scuba diving fatalities

Statistics

• Records and analysis
• Analysis hindered by poor investigation and recording procedures and lack of access to inquest records.