Post-dive procedures requirements

You must check the diver's physical condition immediately after the dive to ensure they show no signs of illness or injury. See 1910.423(b)(1)(i).

• Look for obvious signs of distress (confusion, breathing difficulty, numbness, severe joint pain, skin mottling).
• Ask the diver how they feel and whether they have any new symptoms.
• If symptoms are present, follow the procedures in 1910.423(d)(3) for recording suspected decompression sickness and provide or arrange for immediate treatment.

Employers must tell divers to report any physical problems or symptoms of decompression sickness right away. See 1910.423(b)(1)(ii).

• Give clear examples of symptoms (joint pain, dizziness, numbness, fatigue, difficulty breathing) so divers know what to report.
• Provide both verbal instruction and a readily available way to report (radio, phone, or in-person) immediately after surfacing.
• Document the instruction in dive records under 1910.423(d)(1).

Employers must tell divers where a decompression chamber that is ready for use is located. See 1910.423(b)(1)(iii).

• Provide the physical location and contact method (on-site chamber, nearby facility) and ensure divers can reach it quickly.
• If a chamber is required by 1910.423(c), confirm it is operational and within the required distance.

Employers must warn divers about the potential hazards of flying (or ascending to altitude) after diving. See 1910.423(b)(1)(iv).

• Explain that flying soon after diving increases the risk of decompression sickness because cabin altitude reduces ambient pressure.
• Provide specific time recommendations consistent with dive tables or medical guidance and record that the warning was given in the dive record under 1910.423(d)(1).

A diver must remain awake and near a ready-to-use decompression chamber for at least one hour after dives that are outside no-decompression limits, deeper than 100 fsw, or that use mixed gas. See 1910.423(b)(2).

• This one-hour rule includes any decompression or treatment time that occurred during the dive.
• Make sure the chamber is at the dive location and available during that period per 1910.423(c)(6).

A decompression chamber rated to at least 165 fsw (6 ATA) must be available at the dive location for surface-supplied air dives deeper than 100 fsw and shallower than 220 fsw, for mixed-gas dives shallower than 300 fsw, and for dives outside no-decompression limits shallower than 300 fsw. See 1910.423(c)(1) and its subparts 1910.423(c)(1)(i), 1910.423(c)(1)(ii), and 1910.423(c)(1)(iii).

• Confirm chamber capability before the dive and document its availability in pre-dive planning.

For any dive deeper than 300 fsw, a decompression chamber capable of recompressing to the maximum dive depth must be available at the dive location. See 1910.423(c)(2).

• Planning for deep dives must include logistics to have that chamber onsite or within the required proximity before the dive begins.

The decompression chamber must be dual-lock, multiplace, and located within 5 minutes of the dive location. See 1910.423(c)(3) and its subparts 1910.423(c)(3)(i), 1910.423(c)(3)(ii), and 1910.423(c)(3)(iii).

• Dual-lock means two separate lockable entry points so patients can be transferred without losing pressure integrity.
• Multiplace means the chamber can accommodate multiple occupants (divers and attendants) for treatment and monitoring.
• "Within 5 minutes" requires either the chamber be onsite or reachable within that time under normal conditions.

A decompression chamber must have a pressure gauge for each pressurized compartment, a built-in breathing system with at least one mask per occupant, two-way voice communications to the dive team, a viewport, and interior illumination capability. See 1910.423(c)(4) and its subparts 1910.423(c)(4)(i) through 1910.423(c)(4)(v).

• Verify these features before operations and include them in the dive-site safety checklist.

You must have treatment tables, appropriate treatment gas for the diving mode, and enough gas to conduct treatment available at the dive location. See 1910.423(c)(5).

• Treatment plans and gas supplies should be sized to support potential recompression sessions and kept ready with trained operators.

A dive team member must be available at the dive location during the dive and for at least one hour after the dive to operate the decompression chamber when one is required or provided. See 1910.423(c)(6).

• Ensure trained chamber operators are scheduled for the entire dive window and the one-hour post-dive period in accordance with 1910.423(b)(2).

You must record and keep the dive team members' names (including the person-in-charge), date/time/location, diving modes, general work performed, approximate underwater and surface conditions, and each diver's maximum depth and bottom time. See 1910.423(d)(1).

• Keep this record in a retrievable format and store it according to your company policy for incident review and regulatory inspection.

For those dives you must also record depth-time and breathing gas profiles, the decompression table designation (including modifications), and elapsed time since last pressure exposure if less than 24 hours or the repetitive dive designation for each diver. See 1910.423(d)(2) and its subparts 1910.423(d)(2)(i), 1910.423(d)(2)(ii), and 1910.423(d)(2)(iii).

• Keep complete profiles to support any medical evaluation or incident assessment.

If decompression sickness is suspected or symptoms appear, you must record a description of symptoms (including depth and time of onset) and a description and results of treatment. See 1910.423(d)(3) and its subparts 1910.423(d)(3)(i) and 1910.423(d)(3)(ii).

• These records support medical follow-up and are needed for the decompression procedure assessment under 1910.423(e).

You must investigate and evaluate each decompression sickness incident using recorded dive information, past performance of the decompression table used, and individual susceptibility. See 1910.423(e)(1).

• This includes reviewing dive profiles, gas use, table selection/modifications, and any medical factors that may have contributed.

You must take appropriate corrective action to reduce the chance the decompression sickness will happen again. See 1910.423(e)(2).

• Corrective actions can include changing decompression procedures or tables, additional training, equipment changes, or medical screening updates.

You must prepare a written evaluation of the decompression procedure assessment, including any corrective action taken, within 45 days of the decompression sickness incident. See 1910.423(e)(3).

• Keep the written evaluation on file and make it available for review by dive team members and regulators.

A decompression chamber must include a built-in-breathing-system with at least one mask per occupant. See 1910.423(c)(4)(ii).

• Ensure masks fit and that treatment gas sources are compatible with the diving mode and treatment tables in use per 1910.423(c)(5).

The decompression chamber must have two-way voice communications between occupants and a dive team member at the dive location. See 1910.423(c)(4)(iii).

• Test the communication system before diving and during use to ensure continuous monitoring and coordination.

Employers must ensure a suitable decompression chamber, trained personnel, required treatment gases, and documented emergency procedures are available at the dive location when the dive parameters trigger chamber requirements. See 1910.423(b) and 1910.423(c).

• Pre-dive planning should identify whether the dive will be outside no-decompression limits, deeper than thresholds (e.g., >100 fsw), or mixed-gas to determine chamber capability needs per 1910.423(c)(1)-(2).
• Assign and document a trained chamber operator available during and for at least one hour after the dive per 1910.423(c)(6).

The standard specifies which information must be recorded but does not set a fixed retention period; however, you should retain records long enough to support incident investigations, medical follow-up, and the written evaluation required by [1910.423(e)(3)]. See 1910.423(d) and 1910.423(e)(3).

• Make dive records available to dive team members and to OSHA upon request.
• Consider keeping records for the duration recommended by your company or medical advisors, especially after decompression incidents.

It means the decompression chamber must be sited so an injured diver can be placed in the chamber and pressurized within about five minutes under normal conditions. See 1910.423(c)(3)(iii).

• Plan the dive site layout, transport method, and staffing so transfer time to the chamber consistently meets that timeframe.
• Document the means of transfer and estimated timing in pre-dive procedures.

Use the dive type and depth thresholds in 1910.423(c)(1) and 1910.423(c)(2): a 165 fsw chamber is required for surface-supplied air dives >100 fsw and <220 fsw, mixed-gas dives <300 fsw, and dives outside no-decompression limits <300 fsw; any dive >300 fsw requires a chamber capable of recompressing to the dive's maximum depth.

• Plan equipment availability before the dive based on these clear thresholds.

You can rely on an off-site chamber only if it meets the timing and capability requirements of the standard (e.g., within 5 minutes and rated appropriately for the dive); otherwise you must have a compliant chamber at the dive location. See 1910.423(c)(2)-(3) and 1910.423(c)(3)(iii).

• If an off-site facility cannot meet the proximity or pressure-capability requirements, arrange for an on-site solution or modify the dive plan to avoid triggering those requirements.