This document sets out what is considered to be good practice for ensuring a safe degree of isolation is established prior to conducting diver intrusive works on any energy-conveying system in which pressure differentials, electrical power or laser power may exist at levels which - on loss of containment - would be harmful to personnel or cause damage to the environment or equipment.

The guidance is primarily aimed at project managers, project engineers, offshore construction managers, diving supervisors and safety personnel, all of whom have a responsibility for developing safe schemes of isolation and intervention for divers accessing subsea systems. Additionally, engineering personnel involved with the design of such systems should also use this document to ensure that all new (or being modified) subsea systems incorporate adequate isolation facilities.

The guidelines are applicable for use when preparing scopes of work, procedures, reviews and risk assessments for any diving-related work.