Functional Safety 2014

There are over 100 offshore oil and gas installations in the North Sea which are in UK waters ranging

from smaller structures in the Southern North Sea to very large and heavier structures in the Northern

North Sea.

It is estimated that about 80% of the Electrical, Electronic Programmable Electronics Systems (EEPES)

for Emergency Shutdown, Process Shutdown and Fire & Gas applications (1

Generation systems such

as TMR) currently running in the process industry are in classic lifetime phase, and were installed before

the publication of current industry good practice safety standards such as – IEC 61508 / IEC 61511.

Note also that these systems were not originally subject to the present demands placed onto the

operators to run the assets longer than first envisaged. This demonstrates the challenge we face in not

just operating and maintaining new projects using the current 2

generation SIS which have high

availability and reliability through diverse technology (e.g. the ABB AC800M HI Safety system) but also

the legacy systems as identified above.

In essence, and to address the challenge of continued operations using a mix of technology systems,

many operating companies require operations and maintenance services that encompass the following

requirements:

Integrated automation and electrical products and systems for optimised manufacturing

Engineering, procurement and construction services that meet manufacturing requirements and

cost

Operations and maintenance services that provide a platform for continued operational success

1.2. Background

High hazard manufacturing and facilities operations and maintenance encompasses a broad spectrum

of technical activities that are required to assure the manufacturing environment will safely perform at

the optimised profitability level for continuous time periods for which the facility was designed and

constructed.

Operations and maintenance activities typically includes the day-to-day activities necessary for the

process plant and its supporting utilities systems and equipment to perform their intended function within

the notional technical design limits.

According to the EASHW,

‘regular maintenance is essential to keep equipment, machines and the work

environment safe and reliable. Lack of maintenance or inadequate maintenance can lead to dangerous

situations, accidents and health problems. Maintenance is a high-risk activity with some of the hazards

resulting from the nature of the work. Maintenance is carried out in all sectors and all workplaces’.

In the context of the IEC 61508 and IEC 61511 standards, it is essential that all hardware and/or

software modifications related to any SIS, which are in operation, are properly planned, reviewed and

approved prior to the execution of these activities.

Operations and maintenance activities are therefore managed as a combined entity because a

processing facility cannot operate at peak efficiency and corresponding profitability without being

maintained; therefore the two are planned and as managed as one. This will therefore be implemented

as either PM or CM which are both further defined as:-