In principle, modern alarm systems provide process operators with an essential tool in managing plant operations and minimising unplanned abnormal events, such as plant outage or equipment damage.
In the multiple lines of defence of any process plant, they provide an invaluable layer of protection, combining the flexibility and adaptability of the plant operator with the power of technology.
However in practice, poor initial design and lack of effective alarm management have resulted in alarm systems that are not “fit for purpose”. In many cases the system ceases to be a decision support tool and becomes a noisy distraction to be ignored, or in the worst case, may distract or confuse the operator and compromise his response to an abnormal situation.
Over the years, the most extreme cases of this have led to a number of incidents in which poor alarm management has been seen as a key contributing factor e.g. Texaco Milford Haven, BP Texas City and Three Mile Island.
Good alarm management not only reduces the risk of a major plant incident by enabling good decision making in complex and stressful situations, but also brings a host of other benefits:
- Increased production and equipment availability
- Reduced equipment maintenance costs
- Smoother run ups / run downs
- Reduced outage for maintenance
- Reduced equipment damage
- Reduced demand on protective systems
- Lower risk of incidents with serious safety, environmental or financial consequences
Realising that you have a problem with your alarm system may be the first step to achieving these benefits. An alarm review will establish compliance with recognised good practice such as the EEMUA 191 guideline and ISA 18.02 standard. It provides a ‘where are we now’ analysis and represents the benchmark phase of a total alarm management initiative.
Although it is effective as a stand-alone exercise it can also serve as the first step in a larger alarm improvement programme, which should comprise the following elements:
- Integration of alarm management principles into new projects and plant modifications
- Improvement project to remediate alarm issues on existing systems
- Establishing a framework for ongoing alarm management
- Building a team with clear responsibility and motivation to deliver and maintain an effective alarm management system and the associated benefits
Companies that treat their alarm system as a key production asset; seeing the need for ongoing management to identify any problems and working to continuously improve their system are on the journey to improve. ABB Consulting has significant history of successful alarm improvement projects based on our experience and a broad range of professional skills.