Miura Peninsula and Sagami Coast

Before Entering

• Agree on the entry, exit, depth, buddy procedures and recall signals. Share certification, recent experience and relevant medical information with the operator.
• Confirm thermal equipment and competence with it, especially for drysuits.
• Ask who carries oxygen, how emergency calls are made and where an ambulance can meet the group.
• Keep recreational routes in open water. Descriptions of overhangs or historic debris do not establish permission or training for penetration.

For freediving, use trained supervision and a dedicated buddy system; never practice alone or hyperventilate. DAN's freediving risk guidance explains the need for rescue planning. Plan substantial freediving and scuba on different days, with instructor and dive-medical advice for the actual profiles. DAN discusses the combined-activity risks.

Flights and Altitude

For divers without decompression-sickness symptoms, DAN recommends at least 12 hours after one no-decompression dive and at least 18 hours after repetitive or multiday no-decompression diving before flying. Longer intervals add margin; decompression diving needs a longer plan. Do not fly with suspicious symptoms. Check altitude exposure separately before a mountain excursion. DAN flying-after-diving guidance.

For serious illness or injury, call 119; for an emergency at sea, call 118. Give the exact access point or vessel position and say that diving was involved. The operator should have immediate first-aid arrangements and coordinate evacuation. Do not wait for an insurance callback before requesting emergency services. DAN Japan prioritizes emergency responders.

DAN Japan's +81-3-3812-4999 hotline is a 24-hour member service for diving emergencies and referral support. Visitors should also retain their own insurer or DAN-region emergency number. The JNTO Visitor Hotline can assist with language and finding medical care, but it is not rescue dispatch. JNTO emergency guidance.

No guaranteed 24-hour recompression receiving facility within these three bases was established. Yokohama Rosai Hospital published an indefinite suspension of hyperbaric treatment in August 2024; reopening was not verified during this review. The hospital notice makes old chamber lists an unreliable evacuation plan. Emergency responders and dive-medical specialists should identify a facility that can accept the patient at the time; no transfer time is promised.

At Shibasaki, leave animals, plants and rocks in place, avoid damaging the habitat, and follow the protected-area rules. Hayama Town identifies the coast and surrounding waters as a municipal natural monument.

Kanagawa protects fishery resources and restricts harvesting methods. Do not collect shellfish, seaweed, sea cucumbers or other marine life, and do not treat a dive booking as a fishing entitlement. Remain clear of working nets, boats and aquaculture. Prefectural coastal rules provide the legal detail. Keep fins and equipment off animals and vegetation, remove your litter, and leave any restoration work to an authorized supervised program.

Know the nearest tsunami evacuation route before entering the water. Follow warning flags and instructions, leave coastal areas immediately when directed, and remain away until warnings are cleared. JMA tsunami guidance.