The term "diving activity" includes snorkeling or scuba (aqualung) diving.
The term "snorkeling" as used in the preceding paragraph refers to diving equipped with diving goggles, flippers, or a snorkel; the term "scuba diving" refers to diving equipped with diving goggles, flippers, a breathing tube, and breathing apparatus.

A person engaging in scuba diving activity shall possess a diving certificate issued by a domestic or foreign diving institution.

A person engaging in diving activity shall abide by the following provisions:
1. A dive flag shall be placed in the middle of the area of water where the diving activity is taking place, and the divers shall take surface marker buoys (lift bags) to mark their diving positions.
2. Persons engaging in scuba diving activity shall be accompanied by a qualified person who holds diving certification issued by a domestic or foreign diving institution and who is familiar with the diving location.

Anyone who takes customers to engage in diving activities shall abide by the following rules:
1. A person employed to take customers to engage in scuba diving activity shall possess certification as a qualified diving instructor issued by a domestic or foreign diving institution, and each such employee may take a maximum of ten persons on each aqualung diving activity.
2. A person employed to take customers to engage in snorkeling activity shall possess qualifying certification from the responsible authorities or an organization authorized by those authorities to conduct instruction and training, and each such employee may take a maximum of ten persons on each snorkeling activity.
3. A person engaging in aqualung diving activity shall furnish documentary confirmation of his or her possession of diving proficiency certification.
4. A person employed to take customers to engage in diving activity shall be fully familiar with the conditions in the diving location, and must accurately inform the divers thereof, including informing them of at least the following matters: the time limit of the activity, the depth limit, the water-current direction, the underwater terrain, dangerous areas, and the concepts and rules of environmental protection; and shall stop the activity if he or she fails to receive the compliance of any member of the diving group.　He or she shall also instruct the divers to take into consideration their state of health and stamina.
5. Surface marker buoys (lift bags) shall be taken on every diving activity, and a dive flag shall be put in place in the diving location.

A boat used for taking customers to engage in diving activity shall be equipped with a platform or ladder as needed by divers for getting on and off the boat, and also shall be equipped with a mobile telephone or other communications equipment that has waterproofing and a satellite positioning function, to be kept on the person of the diving instructor for contact and communications purposes.

A boat captain or pilot taking customers to engage in diving activity shall abide by the following rules:
1. Shall make sure prior to departure that communication equipment is in sound working order.
2. Shall be fully familiar with the conditions at the diving location, and accurately inform the divers thereof.
3. Shall raise a dive flag on the boat at all times when passengers are in the water engaging in diving activity.
4. Shall keep the boat at the diving location until the divers have concluded their diving activity and returned to the boat.　In the event that a diver has failed to conclude the activity and return to the boat on time, shall use communication and related equipment to call for help, shall conduct search and rescue in the diving area, and shall not sail the boat away from the diving location before support vessels have arrived there.