API RP 2FB-2006 pdf free download

API RP 2FB-2006 pdf free download.Recommended Practice for the Design of Offshore Facilities Against Fire and Blast Loading.
2.3 NOMINAL LOADS Nominal loads for fires have been in use since the publication of the Interim Guidance Notes [24] in 1993, and have been updated and extended in more recent references [16]. For fires, these take the form of recommended radiation levels and flame temperatures for pool and jet fires in confined and open conditions. Jet fires may give rise to radiation levels up to 300 kW/m 2 in open conditions whereas in confined situations radiation levels may rise to 400 kW/m 2 where re-circulation of the flow occurs. Pool fires generally give rise to lower radiation levels of the order of 100-160 kW/m 2 . For blast considerations, the nominal loads are space averaged peak blast overpressures determined for specific platform types from a set of data. The details are provided in the section C6.3 of the Commentary. If available and considered suitable for use for the particular facility, these nominal loads may be used for the assessment of the platform. The sensitivity of the available data set will determine whether assessment using nominal load cases should be restricted to preliminary design only. Nominal loads are intended for use at an early project phase where Safety input is most effective and detailed geometry of the layout, particularly small bore pipe work, is not known. They may be applied as static loads if this can be justified. Each element of the structure will respond according to its natural period and resistance. An alternative method presently under development [46], the response spectrum method takes into account variations in natural periods and allowable plastic deformations (ductilities). The method is briefly described in the section C6.3 of the Commentary.
2.4 EVENT BASED Fire and blast events originate from the release of hydrocarbons. Causes of release may include dropped objects, ship impact, intervention, fatigue, corrosion, wear, vibration, extreme environmental conditions, imperfections and/or faulty equipment, exceedance of design conditions and human error [37]. Generic release scenarios based on historic evidence in the Gulf of Mexico [35] and the UK sector of the North Sea [36] can be found in the references cited. The event based assessment process is intended to be a series of evaluations of specific events that could occur for the selected platform over its intended service life and service function(s). For facilities not considered as low-risk (see Section 2.2) and where nominal loads (see Section 2.3) are not considered applicable, the risk assessment process should identify the risk levels for each credible fire and blast event. A formal hazard identification study will usually be required for the definition of credible events and assessment of the associated risk. More detailed guidance on hazard identification is available in the API RP 14 series and other sources [7,16,24]. For each credible event, the need for consideration within the structural design of the facility should be determined using the flow chart shown in Figure 2.8-1. Low Risk: Insignificant or minimal risk that can be tolerated because of low potential for escalation and no significant impact on either life safety or the environment. This level of risk need not be considered further for structural design purposes. Medium Risk: The risk level requiring further study or risk assessment may be needed to better define the risk level, consequence and cost of mitigation. In some instances, medium risk may be deemed acceptable as low as reasonably practicable (ALARP) when the effort and/or cost of mitigation become disproportionate to the benefit.