Guide for Fire Hazard Assessment of Rail Transportation Vehicles
|Publication Date:||10 July 2000|
|ICS Code (Equipment for railway/cableway construction and maintenance):||45.120|
1.1 This is a guide to developing fire hazard assessments for rail transportation vehicles. It has been written to assist professionals, including fire safety engineers, who wish to prepare fire hazard assessments of rail transportation vehicles, including assessments for possible use in the design of such vehicles.
1.1.1 Potential users of this guide include professionals, who may assist manufacturers of materials, components, or products for use in rail transportation vehicles, manufacturers of the actual rail transportation vehicles, designers of such rail transportation vehicles, or specification writers.
1.2 Hazard assessment is a process resulting in the development of an estimation of the potential severity of the fires that can develop under defined scenarios, once defined incidents have occurred. Hazard assessment does not address the likelihood of a fire occurring. Hazard assessment is based on the premise that an ignition has occurred, consistent with a specified scenario, and that potential outcomes of the scenario can be reliably estimated.
1.3 This guide cannot be used for regulation. It is not in itself a fire hazard assessment but only a guide for developing a fire hazard assessment. Moreover, it does not give instructions on acceptance criteria or recommendations, which only can come from a specifier or an authority having jurisdiction.
1.3.1 Selective use of parts of the methodology in this guide and of individual fire- test- response characteristics from Table X1 does not satisfy the fire safety objectives of this guide or of the table. This guide shall be used in its entirety to develop a fire hazard assessment for rail transportation vehicles or to aid in the design of such vehicles.
1.4 This guide includes and applies accepted and clearly defined fire safety engineering techniques and methods whose applications are consistent with both existing, traditional prescriptive codes and standards and performance based fire codes and standards under development throughout the world.
1.5 This guide is intended, among other things, to be of assistance to personnel addressing issues associated with the following areas.
1.5.1 Design and specification of rail transportation vehicles.
1.5.2 Fabrication of rail transportation vehicles.
1.5.3 Supply of assemblies, subassemblies, and component materials, for use in rail transportation vehicles.
1.5.4 Operation of rail transportation vehicles.
1.5.5 Provision of a safe environment for all occupants of a rail transportation vehicle.
1.6 This guide is intended among other things, to provide assistance in mitigating potential damage from fires in rail transportation vehicles; thus, it provides recommended methods to accomplish this overall objective. Such methods could include changes to the materials, components, products, assemblies, or systems involved in the construction of the rail transportation vehicle or changes in the design features of the vehicle, including the number and location of automatically activated fire safety devices present (see 4.4.4 for further details).
1.7 The techniques used in this guide can be used for help in assessing the comparative fire hazard of particular products, assemblies, or systems intended for use in rail transportation vehicles. This is accomplished by providing standard bases for quantifying levels of fire safety associated with particular design choices made.
1.8 Consistent with 1.2, this guide provides designers, railtransportation vehicle builders, and operators with methods to estimate whether particular rail passenger designs provide an equal or greater level of fire safety when compared to designs developed based on the traditional applicable fire-test-response characteristic approaches currently widely used in this industry. Such approaches are typically based on the traditional guidelines of the Federal Railroad Administration (FRA) and recommended practices of the Federal Transit Administration (FTA). The performance-based methods provided will differ from commonly used material or product specifications and selection processes and from prescriptive selection processes, traditionally used in common rail transportation vehicle design methodologies.
1.9 The techniques provided in this guide are based on specific assumptions in terms of rail transportation vehicle designs and fire scenarios. These techniques can be used to provide a quantitative measure of the fire hazards from a specified set of fire conditions, involving specific materials, products, or assemblies. Such an assessment cannot be relied upon to predict the hazard of actual fires, which involve conditions other than those assumed in the analysis.
1.10 In terms of design and construction and consistent with 0the statements in 1.2, this guide provides the means for estimating fire hazards associated with the design and construction features of a given rail transportation vehicle, and acknowledging that such fire hazards may be affected by the anticipated use pattern of the vehicle. Characteristics of the vehicle analyzed must include specific designs, fabrication techniques, and materials of construction for the actual use intended. The predicted fire hazard will depend upon specific design and construction assumptions made and will not apply to vehicle designs based on other assumptions.
1.11 This guide can be used to analyze the estimated fire performance of the vehicle specified under defined specific fire scenarios. Under such scenarios, incidents will begin either inside or outside a vehicle, and ignition sources can involve vehicle equipment as well as other sources. The fire scenarios to be used are described in detail in Section 9.
1.12 The techniques provided in this guide do not address vehicle performance under fire scenarios other than those that are defined as part of the fire hazard assessment made. For example, fires with more severe initiating conditions than those assumed in an analysis may pose more severe fire hazard than that calculated using the techniques provided in this guide. For this reason severe conditions must be considered as part of an array of fire scenarios. In addition, the assessment techniques provided in this guide do not necessarily predict the hazard of actual fires which involve conditions other than those assumed in the analyses made (see Section 9), especially in cases where a more severe fire challenge than the ones assumed occurs.
1.13 This guide is to be used to predict or provide a quantitative measure of the fire hazard from a specified set of fire conditions involving specific materials, products, or assemblies. This assessment does not necessarily predict the hazard of actual fires, which involve conditions other than those assumed in the analysis.