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OCR for page 93
94 The following safety provisions have been applied in road munication or in the use of technical systems, such as fire tunnels worldwide (emergency passenger exit for users): hydrants. A common exercise plan between the emergency services and the tunnel operator staff is especially important. Parallel escape tubes (egress corridor) Emergency cross passages to a parallel tunnel The need for specific tunnel rescue facilities or equipment Shelter is analyzed and incorporated into the emergency services Direct pedestrian emergency exit (shafts, portals). normal rescue facilities if it is found favorable from an effi- cient and safe rescue point of view. Appendix F4 (web-only) provides comparison tables on tunnel egress requirements in different national (including In event of an accident, an efficient and clear alarm for NFPA 502, 2008 edition) and international standards. It cov- resources is essential. When emergency services from differ- ers parallel escape tubes (Table F4-1), emergency cross pas- ent organizations are involved, special attention needs to be sages (Table F4-2), shelters (Table F4-3), and direct pedestrian paid to the advantages of a computer-based alarm system, emergency exits (Table F4-4). ensuring that all involved parties receive the same information. The comparison shows that cross passage vehicle accesses The emergency services and the tunnel operator regularly are required by the international standards, if possible, with a perform common functional tests to demonstrate the technical distance of approximately 1 km (3,280 ft). Turning areas shall functionality as well as the staff's ability to handle the equip- be provided for long tunnels. ment, such as the communication radios. It is essential that reliable, efficient, and fast communication be established for the rescue staff internally in the tunnel and externally with the TUNNEL INCIDENT RESPONSE AND INTERNATIONAL rescue centers. The rescue forces must be able to communicate STANDARDS REQUIREMENTS at least with their own control center during the incident to The strategies adopted by the emergency services will recog- obtain the information about the cause of the event. They also nize that an accident could rapidly escalate into a major inci- need to be able to communicate between the inside of the tun- dent and that a fast response is necessary. Tunnel rescue nel and their control center. strategies in an emergency organization are planned, tested, and implemented. The tunnel operator coordinates the rescue Coordinated interventions are always to be performed strategy. A communication strategy is essential in tunnels. according to the rescue plans, at least with regard to the num- ber of resources for the initial rescue phase. The intervention Another important issue may be how to enter a particular follows plans concerning how and in which way to enter the tunnel in a safe way. Access times for the emergency services tunnel. It also shows how to organize the rescue vehicle dis- can be analyzed from different perspectives, including the position, both inside the tunnel and for resources waiting out- location of the accident, turnout from the rescue station, side the tunnel. Special consideration shall be given to means turnout from another place or, if relevant, with reserve rescue and methods to remove victims. forces when the normal forces are occupied. The following means for emergency access for rescue The conditions within the tunnel and the exposure limits staff has been used in road tunnels worldwide: are identified and reviewed regularly so that proper precau- tions can be taken by rescue staff in a fire situation. Separate emergency vehicular access gallery Cross-passage vehicular access An emergency response plan is implemented for prede- Emergency lane fined events. This specifies the initial responses and so forth Direct pedestrian access (lateral, upstairs, shaft) as defined in NFPA 502. Specific rescue effort plans are to Turning areas be made based on the emergency response plans. Also insti- Emergency services station at portals. tuted is a common information/media plan, which is agreed on between the emergency services and the tunnel operator. Appendix F5 (web-only) provides comparison tables on This will include providing information activities to media tunnel incident response requirements in different national with the aim of keeping tunnel users and the media focused on and international standards. It covers a separate emergency safety aspects. The plan defines the information responsibilities vehicle gallery access (Table F5-1), cross-passage rescue during and after an accident; specifically, what information the vehicular access (Table F5-2), emergency lane (Table F5-3), tunnel operator can communicate. Also implemented is an direct pedestrian emergency access (lateral upstairs shaft) education plan for all rescue staff, reflecting both the educa- (Table F5-4), turning areas (Table F5-5), and emergency ser- tion of newly employed staff and refresher courses. vices station at portals (Table F5-6). Likewise, an emergency service exercise plan is devel- The size of a fire in a road tunnel will have a considerable oped. These exercises can help to train new staff in com- effect on the ability of the Fire and Rescue Service to perform

OCR for page 93
95 FIGURE 26 Fire fighting timeline (14, 59 ). effective rescue and/or firefighting operations. When tack- The emergency response time is to be based on NFPA ling fires in road tunnels, personnel and equipment need to be 1710. Figure 26 provides a tunnel fire fighting timeline. capable of dealing with fires of any magnitude. How much water will be needed to put out the fire? This Handling fires from private cars within twin-bore tunnels is an important question to answer, as it determines the will almost always be within the capabilities of a firefighting number of jets used over a certain period of time. In turn, force. However, the same fire in a single-bore tunnel could these jets require a certain number of firefighters, working lead to considerable difficulties, depending on whether there under difficult conditions. The quantity of water needed to is any airflow through the tunnel or whether there is a venti- extinguish a vehicle fire in a tunnel, based on the extin- lation system capable of evacuating smoke from the fire or guishing requirements for fires occurring in nonresidential fixed fire suppression system available. buildings, is given in Table 29. In such instances, the fire- fighters had direct access to the fire. In this context, we The factors that will set the capacity requirements for need to remember that vehicle fires are particularly difficult fighting a fire in a tunnel will be: to put out, which means that the following simplifications must be seen as an absolute minimum requirement in terms The number of people that the rescue and fire services of water quantities. must assist to safety. The size of the fire and thus the temperature and thermal The firefighters need to get close to a vehicle on fire to radiation power that will face the firefighters. fight the fire because of the low ceiling of the tunnel. The The distance that the firefighters have to travel in a water flow rate then has to be maintained for a significant smoke-filled environment to reach the fire. period to put out the fire. It may take about 30 min, with at least the 1,250 l/min quantity of extinguishing water, to put Fires in trucks, and especially gasoline tanker fires, are out a fire in a truck. It would be possible to deal with fire likely to reach output levels that it can be difficult to effec- gases using ventilation to increase the airflow; however, tively contain. thermal radiation from the fire and from any residual back- TABLE 29 ABSOLUTE MINIMUM WATER REQUIREMENTS FOR EXTINGUISHING A VEHICLE FIRE Minimum Extinguishing Water Type of Fire Area Heat Release Requirement Number of Vehicle (m2) (MW) (l/min) 360 l/min Jets Private Car 10 5 226 1 Van 35 15 462 2 Truck 200 100 1,250 4 Sources: Rhodes and MacDonald (20) and Ingason et al. (64).