Activity to be performed by a facility will be where the executing unit is connected to a subsea well with intervention equipment entering the well, and the unit has primary control of the wells’ block valves.
Primary control of the wellstream (christmas tree valves or well control equipment connected to the well) is handled by the executing unit (from control room and/or direct operation of check valves).
Surveillance/monitoring of the subsea well’s christmas tree can take place at the same time from another facility. Facility activities shall be carried out by a facility with AoC.
Examples of such activities include wireline work and coiled tubing work in subsea wells where the equipment string/components are physically fed through the christmas tree and well control equipment in/out of the well.
Source: Guidelines Regarding the Framework Regulations, Norway, updated December 2012. Regulatory Guidance