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Functional Safety Experts
In the wake of the Buncefield disaster, work process operators are being called upon to demonstrate the safety of their processes, particularly if they are a COMAH (Control of Major Accident Hazards) Site.
IEC 61508 and it’s process industry orientated cousin, IEC 61511, sets out a formal process for establishing the required reliability of functional safety systems and for demonstrating that these systems meet the necessary reliability levels.
Safety and Engineering Managing Directors have the responsibility to implement functional safety systems management procedures. To ensure conformance, the correct applications need to be in a place by a process of training and management, ongoing audits are then required to ensure continuing compliance. In order to establish and maintain the management of functional safety systems the following steps should be established:
Develop a management procedure. Generic templates are available on line www.sipi61508.com/ciks/cikscontents.htm More specifically - TAS can provide project specific ‘boiler plates’.
Implement a training / awareness programme, highlighting the role of functional safety systems, and the impact upon the workforce and site.
Develop and calibrate risk graphs and LOPA (layer of protection analysis) techniques for the specific work processes. It is very important that generic risk graphs are not employed. Care & attention needs to be given to the specific risk & impact of failures on the work process.
Determine the required SIL (safety integrity level) for functional safety systems. This means establishing just how reliable a function safety system needs to be to fulfil its intended purpose.
Document existing safety systems to ensure that all system drawings are accurate and data records are up to date.
Assess the reliability of installed safety systems, ensuring that they meet the required SIL levels. Improve systems if necessary.
Establish proof test procedures & intervals & maintenance regimes.
Maintain records of testing and maintenance.
Maintain records of demands made on functional safety systems & make notes of the outcomes.
Regularly audit compliance with system requirements and implement any improvement actions that are necessary.
NOTE
The needs of the environment and of the business should also be considered. By providing protection against safety hazards, instrument systems also protect against harm to the environment and to the business.
Arc Flash in Brief
The temperature from an arc flash can reach 20,000 degrees Celsius.
A typical arc flash incident can produce more explosive energy than a pound of TNT.
The energy released in the fault instantly vaporises metal conductors.
The metal plasma arc produces a massive amount of light energy from infrared to ultraviolet.
Any object in the vicinity absorbs this energy and is instantly heated to vaporising temperatures.
Circuit breakers do not prevent arc flash.
2,000 workers are admitted to burns centres with arc flash injuries each year in the US alone.
 Download Flashpoint: Arc Flash Awareness PDF
Our thanks to IML Group for the article above which appeared in the November 2007 issue of Electrical Products and Applications journal.
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Flashpoint: Arc Flash Awareness
“Safety and Engineering Managers and Directors have the responsibility to implement electrical systems risk assessments and preventative measures. But in this dynamic environment, where multiple projects, plus ever increasing workloads, make high demands on the professional’s time and overstretched staff, completing prioritised projects can sometimes be challenging” says John Maplesden, MD of TAS Engineering. In order to help reduce the risk of electrical arc flash, there are a number of steps which can be implemented:
