Pre-dive procedures

Employers must follow a set of planned checks and steps before any dive starts to protect divers and support personnel. Under 1926.1081 (which is identical to 1910.421), pre-dive procedures normally include confirming the dive plan, checking diver fitness and certification, inspecting diving and emergency equipment, establishing surface support and communications, and verifying site conditions and hazards.

• Verify that a written dive plan or checklist exists and is understood by all team members.
• Confirm divers are medically fit and hold required training/certifications.
• Inspect breathing gas supplies, regulators, harnesses, weights, and emergency gear.
• Establish reliable communications and a surface standby person or team.

See the requirements in 1926.1081 and the duplicate provisions at 1910.421 for the formal regulatory reference.

The employer is responsible for ensuring a pre-dive plan exists and is approved by competent persons before diving begins. 1926.1081 (and the identical 1910.421) require employers to implement pre-dive procedures; this duty usually means the employer must designate a competent diving supervisor or other qualified person to develop, review, and approve the dive plan.

• The designated supervisor should ensure the plan addresses hazards, emergency response, communications, and equipment checks.
• Employers must keep records that show the plan was reviewed and that responsible persons were assigned.

Before each dive, the employer must ensure breathing gas supplies and regulators are inspected and verified safe for use. The pre-dive procedures required by 1926.1081 (see also 1910.421) include checking gas purity, cylinder condition, pressure, valve functioning, and regulator performance.

• Confirm gas cylinders are properly labeled and within hydrostatic test dates.
• Verify gas composition and purity (oxygen and other mixes) where applicable and ensure compatible components for enriched gases.
• Inspect regulators, hoses, and O-rings for damage and proper seating; test free-flow and demand performance at surface pressure.
• Ensure reserve or emergency gas supplies are available and accessible.

Document inspections where your dive program requires records as part of the pre-dive checks.

Yes — employers must ensure divers are medically fit and competent before permitting them to dive. The pre-dive procedures in 1926.1081 (and 1910.421) require checking diver qualifications and health status appropriate for the type of dive.

• Verify the diver's training, certifications, and recent dive experience.
• Confirm medical clearance or fitness-for-duty examinations if your program or the specific dive environment requires them.
• Remove or postpone any dive if the diver reports symptoms (e.g., congestion, recent illness) that could increase risk.

Keep records of medical clearances and the competency checks as required by your employer policies and applicable regulations.

Surface support personnel must be identified, briefed, and ready before a dive begins so they can operate communications, manage ropes/lines, monitor the diver, and execute emergency response. 1926.1081 (identical to 1910.421) requires employers to include surface support duties in pre-dive procedures.

• Assign a surface attendant or tender whose only duties are to monitor the diver and maintain contact.
• Ensure surface personnel understand signals, communications equipment, and emergency protocols.
• Verify rescue equipment (boat, tow line, first aid/oxygen) is present, functioning, and operable by surface staff.

Document assigned roles and the briefing in the pre-dive checklist.

Employers must verify reliable communications between diver and surface personnel during pre-dive procedures. 1926.1081 and 1910.421 require confirmation that signals or electronic communications work and are understood by all team members.

• Test voice, hard-wire, or line-pull signals before immersion.
• Confirm backup communication methods (e.g., rope signals, hand signals for shallow dives, or spare communication gear) are available.
• Ensure everyone recognizes the meaning of standard signals and the abort/emergency signal.

If communication fails, the dive must be delayed until it is restored and verified functional.

Yes — employers must evaluate dive site hazards and incorporate that assessment into pre-dive procedures. 1926.1081 (and 1910.421) requires that pre-dive checks consider site-specific risks such as currents, visibility, entanglement hazards, vessel traffic, overhead obstructions, and water contamination.

• Identify and control hazards: mark or remove entanglement risks, restrict vessel traffic, and set exclusion zones.
• Check environmental conditions: current, tide, wind, water temperature, and visibility.
• Confirm hazardous atmospheres or contaminants are addressed (e.g., polluted water, sewage, chemical contamination) and that respiratory/protective measures are in place if needed.

Adjust the dive plan or cancel the dive if hazards cannot be controlled to an acceptable level.

Employers must ensure appropriate emergency equipment is present and functional before any dive. The pre-dive procedures in 1926.1081 and 1910.421 require checks of rescue and medical equipment as part of preparing for dives.

• Verify availability and operation of first aid supplies, oxygen resuscitation equipment, and a means to rapidly recover a diver to the surface (e.g., lift lines, boat, davit).
• Confirm emergency communications (radio/phone) and access to emergency medical services, including directions to the nearest hyperbaric facility when applicable.
• Ensure trained personnel are present to administer first aid and oxygen and to perform rescue operations.

Record that emergency equipment was checked and ready before the dive.

Yes — pre-dive procedures must include review and confirmation of decompression obligations and planned depth/time limits for the dive. 1926.1081 and 1910.421 require that divers and supervisors agree on the dive profile and appropriate decompression tables or computers.

• Confirm planned bottom time, maximum depth, and required decompression stops per applicable tables or dive computer settings.
• Ensure backup plans exist if the dive exceeds planned time or depth (e.g., emergency gas, standby diver).
• Brief all team members on expected profile and actions to take if decompression obligations change.

Keep dive records that document the planned profile and any deviations during the operation.

Yes — pre-dive procedures must include a buddy check or equivalent equipment inspection to ensure diver gear is correctly assembled and functioning. 1926.1081 (and 1910.421) expect employers to include gear inspections as part of pre-dive checks.

• Perform a standardized buddy check that covers cylinder valves, regulator connections, BCD/harness fittings, weight system, and alternate air source.
• Confirm seals and suit integrity for surface-supplied or SCUBA systems.
• Document that checks were completed and correct any defects before entering the water.

If defects cannot be corrected, remove the affected equipment from service until repaired.

Employers should maintain records that show pre-dive procedures were completed and critical checks were made before each dive. 1926.1081 and 1910.421 support keeping documentation demonstrating compliance with pre-dive requirements.

• Examples: written dive plans/checklists, equipment inspection logs, gas analysis certificates, medical clearances, and assignments of surface support/rescue personnel.
• Retain records for the period required by your company policy and relevant OSHA recordkeeping where applicable.

Good recordkeeping helps demonstrate that pre-dive procedures were followed and aids accident investigations.

Yes — employers must verify breathing-gas mixtures are of the correct composition and safe for use as part of pre-dive procedures. 1926.1081 and 1910.421 require that gas safety checks be completed prior to the dive.

• Analyze and record oxygen (and other gas constituent) fractions for enriched or mixed gases before filling or using cylinders.
• Label cylinders with the gas mix and maximum operating depth (MOD) or maximum oxygen partial pressure as appropriate.
• Ensure personnel filling or analyzing gas are trained and use calibrated gas analyzers.

Do not use mixed gases without documented analysis and proper labeling.

If conditions change after pre-dive checks, the employer must reassess hazards and update or postpone the dive as needed. 1926.1081 (and 1910.421) require pre-dive procedures to account for site conditions; therefore changed conditions trigger a new assessment.

• Re-evaluate wind, waves, visibility, current, temperature, and vessel stability.
• Re-check communications, surface support positioning, and emergency plans for any new risks.
• Delay or cancel the dive if hazards cannot be controlled or mitigated.

Document the reassessment and decisions to proceed, modify, or cancel.

Employers must consider diver fitness for duty, including fatigue, during pre-dive procedures and should not allow fatigued divers to dive. 1926.1081 and 1910.421 require assessing diver readiness as part of pre-dive checks.

• Ask divers about sleep, recent workload, illness, medication, or alcohol use that could affect performance.
• Limit consecutive dive hours and manage shift schedules to reduce fatigue where the operation exposes workers to fatigue-related risk.
• If a diver is judged fatigued or unfit, replace them with a rested, qualified diver before proceeding.

Document fitness-for-duty assessments when required by your dive safety program.

Yes — supervisors must brief all team members on the emergency plan as part of pre-dive procedures. 1926.1081 and 1910.421 require employers to ensure everyone understands emergency roles, signals, and response actions.

• Cover rescue procedures, oxygen administration, rapid recovery methods, and communication with medical services.
• Identify who will contact emergency medical services and where the nearest hyperbaric facility is located if required.
• Confirm everyone knows the location and operation of emergency equipment.

A documented briefing is good practice and helps ensure quick, coordinated response in an emergency.

When diving in contaminated water, employers must identify the contamination hazards and include controls in pre-dive procedures to protect divers and support staff. 1926.1081 and 1910.421 require addressing site-specific hazards.

• Test water for chemical, biological, or sewage contamination where feasible and use appropriate personal protective equipment (PPE) such as dry suits and specialized respirators when required.
• Decontamination plans must be established for divers and equipment, and first-aid measures for exposure should be in place.
• Ensure medical follow-up and reporting procedures are available for exposures.

If contamination hazards cannot be controlled to acceptable levels, do not perform the dive.

Employers must verify that each diver and required support personnel have the appropriate training and certifications before they participate in the dive. This verification is a required element of pre-dive procedures under 1926.1081 and 1910.421.

• Check current certification cards or documented training records for divers, tenders, and supervisors.
• Ensure personnel have training specific to the dive type (e.g., surface-supplied diving, mixed-gas diving, confined-space underwater work).
• Provide refresher training or restrict duties if a required skill or certification is expired.

Keep copies or entries in personnel files showing that training/certification verification was completed.

For hazardous or complex dives, employers should designate a properly equipped and ready standby diver as part of pre-dive procedures; this is consistent with the safety expectations in 1926.1081 and 1910.421. A standby diver provides immediate rescue capability.

• The standby diver must be ready, trained, and have the appropriate equipment to execute a rescue.
• Ensure the standby diver’s equipment is inspected and they are briefed on rescue procedures and communications.
• If a standby diver is not required by the specific dive profile, ensure other rapid rescue methods are in place and tested.

Document the assignment of a standby diver or the alternative rescue arrangements in the pre-dive plan.

Employers must inspect and verify any lifting or recovery equipment used for diver retrieval during pre-dive procedures to ensure safe recovery capability. This is part of the pre-dive responsibilities under 1926.1081 and 1910.421.

• Inspect slings, winches, davits, and attachment points for rated capacity, good condition, and proper rigging.
• Confirm operators are trained and competent to use the lifting equipment and emergency retrieval systems.
• Test recovery procedures as part of the pre-dive brief so the crew knows how to recover an unresponsive diver.

Keep inspection records for the hoisting equipment and document any functional tests performed before the dive.

Pre-dive procedures must be repeated or updated at the start of each shift and whenever conditions, personnel, or equipment change during multi-shift or multi-day operations. 1926.1081 and 1910.421 require that dives always begin with current checks appropriate to the operation.

• Conduct a fresh briefing and equipment inspection at the start of each shift or when a new diver or support person comes on duty.
• Reassess environmental conditions, gas supplies, and emergency readiness if the site or schedule changes.
• Update and document any changes to the dive plan to reflect new risks or staffing.

Maintaining up-to-date pre-dive checks helps prevent lapses in safety across shifts.