Ingenieur Vol 68 Oct-Dec 2016 | Page 77

By proactively identifying hazards, assessing and characterising risks via obligatory process hazard analysis, and taking actions to reduce the identified, quantified risks, organisations can prevent accidents and reduce the potential for death, injury, property damage and environmental impacts. The PSM Standards also require written operating procedures for correct operation to ensure that tasks are conducted in a safe manner and in accordance with the safety precautions developed during process hazard analysis. Implementation of mechanical integrity assures that process equipment is in a satisfactory condition to safely and reliably perform its intended design function and operate properly within the limits of established process parameters as documented in the facility’s process safety information. In PSM, relevant changes that can affect the process safety information upon which the process hazards analysis is based, must be managed through the management of change elements to ensure that the operation and maintenance of the process continues in the safest manner possible. An audit to check that the process is operated as required is critical. The main reason for auditing or measuring the process safety performance is to provide ongoing assurance that risks are being adequately controlled. The above describes the significant purpose and integration of some of the PSM elements for safer plant operation. Without question, all the PSM elements are important and must work together to provide the multiple layers of protection that are relied upon for safe operation. Conclusion The layers of protections, even with their inherent flaws, as a whole provide thorough defence for safer process operation. Nevertheless, due to weak competency, extreme operating conditions of the processes, complexity of the processes and the safeguarding systems plus the changes driven by competition, cost pressures, management methods and human behaviour, accidents do still occur. Consequently, the provision of the structured PSM programme elements should systematically work to ensure reliable protection in order to achieve the desired operational safety objectives, which are to eliminate (or greatly reduce) the number and severity of processrelated incidents. REFERENCE [1] Chouhan, T.R. (2005). The unfolding of Bhopal disaster. Journal of Loss Prevention in the Process Industries 18, pp. 205–208 [2] Leveson, N. G., Stringfellow, M., & Thomas, J. (2009).  Systems Approach to Accident Analysis. IT Technical Report. Available: http://sunnyday.mit.edu/safer-world/refineryedited.doc, Accessed August 1, 2015. [3] Reason, J.T. (2008). The Human Contribution: Unsafe Acts, Accidents and Heroic Recoveries. Surrey: Ashgate [4] Center for Chemical Process Safety (CCPS) (1993). Guidelines for Safe Automation of Chemical Processes, American Institute of Chemical Engineers, New York. [5] Center for Chemical Process Safety (CCPS) (2008). Guidelines for hazard evaluation procedures, American Institute of Chemical Engineers, New York. [6] COMAH Competent Authority Investigation Team (July 2007), Buncefield: Why did it happen? Final investigation report, Available: http://www.hse.gov.uk/comah/ buncefield/ buncefield-report.pdf, Accessed July 25, 2015. [7] Knegtering, B. and Pasman, H.J. (2009). Safety of the process industries in the 21st century: A changing need of process safety management for a changing industry. Journal of Loss Prevention in the Process Industries 22, pp. 162-168. [8] Occupational Safety and Health Agency (OSHA) (1992). Process Safety management of Highly Hazardous Chemicals. Available: ht tps://w w w.osha.gov/pls/ oshaweb/ owadisp.show_document?p_ table=STANDARDS&p_id=9760, Accessed August 1, 2015. 75