Hazards analysis offshore

While RP14C provides guidance on the need for process safety devices, it is desirable to perform a complete hazards analysis of tlie facility to identify hazards that are not necessarily detected or contained by process sLifety devices and that could lead to loss of containment of hydrocarbons or otherwise lead to fire, explosion, pollution, or injury to personnel. The industry consensus standard, American Petroleum Institute Recommended Practice 14J, Design and Hazards Analysis for Offshore Facilities (RP14J), provides guidance as to the use of various hazards analysis techniques. 

American Petroleum Institute (API), RP 14J. Recommended Practice for Hazard Analysis for Offshore Platforms. First Edition, API, Washington, D.C., 1994. 

RP 14J—Design and Hazards Analysis for Offshore Production Facilities. 

Most hazards analyses review a subset of a larger system. For example, a refinery hazards analysis team may carry out a hazards analysis on just the catalytic cracking unit, a pipeline company may analyze just the marine loading operations, or an offshore team may analyze just one platform in a larger complex. Yet these subsystems are part of larger systems, which means that hazards can be transferred to or from the other units across the interfaces. 

Hazards analyses should be carried out in accordance with API RP 14J— Design and Hazards Analysis for Offshore Production Facilities . 

This standard brings together in one place a brief description of basic hazards analysis procedures for offshore production facilities. This recommended practice discusses several procedures that could be used to perform a hazards analysis and it presents minimum requirements for process safety information and hazards analysis that can be used for satisfying the requirements of API RP 75. 

Applioation to Offshore Operations Hazards Analysis Methods... 

Process Hazards Analysis (PHA) techniques were developed for the onshore chemical and refining industries. These industries typically work with a much wider range of chemicals than are used offshore, and many of those chemicals are highly toxic and/or corrosive—something that is rarely a major consideration offshore. Therefore, the use of onshore-style PHA methods when analyzing the risks associated with offshore facihties can feel like something of a misfit. Where possible, these techniques should be modified so that problems to do with hazardous chemicals receive less prominence, but other issues, such as dropped objects and escape and evacuation routes, are analyzed more thoroughly. 

Many books and papers, including Process Risk and Reliability Management, explain the various types of hazards analysis techniques that are used. A very brief overview of some of the techniques that are used offshore is provided in this section. 

A hazards analysis technique that is widely used on offshore facilities is known as Bow-Tie Analysis. The name is based on the shape of the final analysis product as shown in Figure 5.1. The method is used not only to identify risks, but also to assess the effectiveness of the system s safeguards. 

Traditionally, the hazards analysis team would use P IDs and PFDs for their base documentation. However, given that a large fraction of the hazards on an offshore facility have to do with layout and the movement of equipment and people, it has been found that it is more useful to project a 3D model of the rig or platform on an overhead screen so that people can visualize what is being talked about. 

As noted above, in the discussion to do with Hazards Analysis, offshore facilities do not generally handle highly corrosive or toxic chemicals, hence reducing the associated integrity problems. However, offshore platforms operate in a marine environment where much of the equipment is exposed to salt water and harsh environmental conditions. 

Vinnem, J.E. (2010) Analysis of root causes of major hazard precursors in the Norwegian offshore petroleum industry , Reliability Engineering and System Safety, 95 (11) 1142-1153. 

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