The diving contractor will need to specify the size of team based on the details of the project and as specified in the diving regulations. For safe operation, this may need to include additional surface support personnel and other management or technical support personnel.

The diving contractor will normally need to provide a sufficient number of competent and qualified personnel to operate all the equipment and to provide support functions to the diving team, rather than relying on personnel provided by others for assistance.

If personnel who are not employed by the diving contractor are to be used in the diving team for any reason they will need to be carefully considered for competence and suitability before being included. Such personnel can create a hazard to themselves and others if they lack familiarity with the contractor's procedures, rules and equipment.

The team size and composition must always be sufficient to enable the diving operation to be conducted safely and effectively. This means that a number of eventualities should be considered when deciding team size and make-up including the following:

The overriding factor must always be the safety of personnel during operation and maintenance. It is the absolute responsibility of the diving contractor to provide a well-balanced, competent team of sufficient numbers to ensure safety at all times.

When a dive is taking place either a diving supervisor will need to be in control of the operation at all times. For large projects, more than one supervisor may be needed on duty. Each supervisor will only be able to provide adequate supervision of a defined area of operations, including dealing with foreseeable contingencies or emergencies.

For umbilicals that are tended from the surface, at least one tender is required for every two divers if the maximum depth of diving does not exceed 30 meters. Whenever diving exceeds 30 meters, at least one tender is required for each diver in the water.

A standby diver will need to be in immediate readiness to provide any necessary assistance to the diver, whenever a diver is in the water. The standby diver will need to be dressed to enter the water, but need not wear a mask or helmet. This equipment however, needs to be immediately on hand. A standby diver should not act as a diving tender without another tender, who is not the supervisor, being available to take over these duties.

There will need to be one standby diver for every two divers in the water. The standby diver will remain on the surface.

With regard to safe working practices, a single person should not work alone when dealing with:

On large projects, dedicated personnel may be required to provide overall management and control. These personnel are often called senior supervisors or diving superintendents.