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151 APPENDIX D Tunnel Safety Projects Additional Description D.2.4 INTERNATIONAL TECHNOLOGY have standards or guidelines specifically for highway SCANNING PROGRAM (2) or passenger and freight rail tunnels. Recently, the AASHTO Subcommittee on Bridges and Structures The nine initiatives and practices listed below relate to human created a new committee, the Technical Committee on factors, planning, design, and incident and asset management. Tunnels (T-20), to help address this problem. T-20 takes the lead in developing AASHTO standards and 1. Develop Universal, Consistent, and More Effective guidelines for existing and new tunnels, working with Visual, Audible, and Tactile Signs for Escape Routes. NFPA, APTA, FHWA, and the appropriate TRB com- mittees on standards and guidelines for highway and The scan team noted that the signs Europeans use to passenger and freight rail tunnels. Tunnel safety mea- indicate emergency escape routes are consistent and sures such as the Mont Blanc Tunnel emergency pull- uniform from country to country. Emergency escape out area and variable message sign showing maximum routes are indicated by a sign showing a white-colored speed limit and required vehicle spacing, as well as running figure on a green background. Other signs that refuge room requirements require considerations. indicate the direction (and distance in meters) to the nearest emergency exit also have the white figure on a 3. Conduct Research and Develop Guidelines on Tunnel green background, as used in European buildings and Emergency Management that Includes Human Factors airports. All SOS stations in the tunnels were identified by the color orange. This widespread uniformity pro- Tunnel design solutions may not anticipate human motes understanding by all people and helps assure behavior. Consistently predicting the way people will that in the event of an emergency, any confusion behave in an incident is difficult. During emergency related to the location of the emergency exit will be min- situations, human behavior is even harder to predict as imized. In addition, the team learned that combining the the stress of the situation replaces intellect with curios- use of sound that emanates from the sign, such as a ity, fear, or even panic. During a tunnel emergency, sound alternating with a simple verbal message (e.g., people often must be their own first rescuers and must "Exit Here") with visual (and, where possible, tactile) react correctly within a few minutes to survive. Tunnel cues, makes the sign much more effective. emergency management scenarios and procedures must take human behavior into account to be fully The U.S. tunnel engineering community relies on effective in saving lives. The European experience in National Fire Protection Association (NFPA) 130, human factor design provides a good basis for the Standard for Fixed Guideway Transit and Passenger United States to discover and include more effective Rail Systems, and NFPA 502, Standard for Road Tun- measures for tunnel planning, design, and emergency nels, Bridges, and Other Limited Access Highways, response. for fire protection and fire life safety design standards. These standards need to incorporate the most current 4. Develop Education for Motorist Response to Tunnel technology and results of recent human response studies Incidents on identification and design of escape portals, escape routes, and cross passages. During an emergency situation, most people do not immediately know what to do to save themselves and 2. Develop AASHTO Guidelines for Existing and New others. Motorists are their own first rescuers and Euro- Tunnels pean studies indicate that self-rescue may be the best first response for a tunnel incident. For this to be an Single-source guidelines for planning, design, con- effective strategy, it is important to educate the public struction, maintenance, and inspection of roads and about the importance of reacting quickly and correctly bridges have been in place for many years. NFPA has to a tunnel incident, such as a fire. developed standards for safety in highway tunnels and passenger rail tunnels. The American Public Trans- 5. Evaluate Effectiveness of Automatic Incident Detec- portation Association (APTA) has general safety stan- tion Systems and Intelligent Video for Tunnels dards and guidelines for passenger rail operations and maintenance that incorporates some of the NFPA The scan team learned of sophisticated software standards by reference. However, AASHTO does not that, using a computer system interfacing with ordinary

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152 video surveillance cameras, automatically detects tracks the structure gained from intelligent monitoring and and records incidents. As it does so, it signals the oper- analysis of the collected data, the owner can use a risk- ator to observe the event in question and allows the based approach to schedule the time and frequency of operator the opportunity to take the appropriate action. inspections and establish priorities. It makes more This concept can also be applied to detect other activi- sense to inspect less critical or more durable portions ties and incidents in areas besides tunnels, including ter- of the system on a less frequent basis and, instead, con- rorist activities, crashes, vandalism and other crimes, centrate inspection efforts on the more critical or more fires, and vehicle breakdowns. fragile components. A risk-based assessment of the condition of facilities also can be used to make optimal 6. Develop Tunnel Facility Design Criteria to Promote decisions on the scope and timing of facility mainte- Optimal Driver Performance and Response to Incidents nance or rehabilitation. This method offers a statistical process to manage the tunnel assets. The Europeans found that innovative tunnel design that includes improved geometry or more pleasing 9. Implement Light-Emitting Diode Lighting for Safe visual appearance will enhance driver safety, perfor- Vehicle Distance and Edge Delineation in Tunnels mance, and traffic operation. For example, the full-size model of one section of the twin roadway tube for the The scan team noted that in several European tun- A-86 motorway in Paris demonstrates the effectiveness nels, light-emitting diode (LED) lights were installed of good lighting and painting to improve motorist safety. along the edge of the tunnel at regular intervals of It is a particularly important consideration for a tunnel approximately 10 to 20 meters (m), or 33 to 66 feet (ft), roadway section designed with limited headroom. to clearly identify the edge of the roadway. These lights were either white or a highly visible yellow color. In 7. Investigate One-Button Systems to Initiate Emergency some tunnels, there were blue lights at 150 m (490 ft) Response and Automated Sensor Systems to Deter- intervals spaced among these edge-delineation lights. mine Response Motorists are instructed through formal (for truck and bus drivers) and informal driver education to keep a The European scan revealed that one of the most safe distance between them and the vehicle in front, and important considerations in responding to an incident that distance is indicated by the spacing of the blue lights. is to take action immediately. For this to be effective, This visual cue is more reliable than asking motorists to the operator must initiate several actions simultane- establish distance between vehicles using speed based ously. An example of how this immediate action is guidelines, such as maintaining one car length spacing accomplished is the "press one button" solution that for every 10 miles per hour (16 kilometers per hour) of initiates several critical actions without giving the speed. The LED markers are also less susceptible to loss operator the chance to omit an important step or per- of visibility because of road grime and smoke during a form an action out of order. From the Mont Blanc tunnel fire. Tunnel operations center control panel, operators can initiate several actions by moving a yellow line over the area where a fire incident is indicated on a com- D.2.5 UPTUN (8) puter screen. This "one-button" action reduces the need for time-consuming emergency decisions about WP1. This work package assesses monitoring and detection ventilation control and operational procedures. systems installed at present, assessed if improvements to those systems could be made, evaluate new methods and tech- The Europeans observed that tunnel operations per- niques for determining incidents and fires inside and outside sonnel have difficulty keeping up with events like tun- tunnels. In order to ensure that the ultimate results of UPTUN nel fires. They believe that an automatic system using are achieved it was necessary to make a detailed database of devices like opacity sensors can help determine the all road tunnels in Europe, detailing the type of tunnels in correct response. A closed-loop data collection and each country, what types of detection systems are in place, analysis system that takes atmospheric conditions, tun- whether any suppression systems are installed, and details of nel air speed, and smoke density into account may best recent incidents. This database was used to analyze these control fans and vents. recent incidents and to assess if tunnels that have better mon- itoring and detection systems achieved a quicker response to 8. Use Risk-Management Approach to Tunnel Safety an incident, which would reduce the impact of an incident Inspection and Maintenance and minimize the economic impact in the surrounding areas. The scan team learned that some organizations WP1 Technical tasks: use a risk-based schedule for safety inspection and 1.1 Categorization and listing of European tunnels. maintenance. Through knowledge of the systems and 1.2 Causes and prevention of accidents and fire.

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153 1.3 Existing detection and monitoring systems. Results of the study were summarized in the paper by 1.4 Exploration of alternative or new technology for detec- Haukur Ingason of SP Swedish National Testing and tion of moving fires, detection of fires outside tunnels, Research Institute "DESIGN FIRES IN TUNNELS" detection of the migration of fires. referenced and further discussed in this report (28). 1.5 Implementation of proposed solutions and prototypes. WP3. The main objective of WP3 was to find, develop, evalu- WP1 Objectives: ate, and promote new methods and means to remove, neutral- To categorize European tunnels. ize or correctly assess all factors that contribute to a negative To identify probabilities of incidents potentially leading human response in incidents (larger accidents always resulted to fires and propose, investigate and promote methods from smaller incidents) and accidents (resulting if no ade- to reduce these. quate action is taken). To list potential suitable existing detection and moni- toring techniques and to investigate reliability of exist- WP3 Technical tasks: ing systems. 3.1 Review of state of the art and interrelation with other To develop innovative measures to detect the fire load projects. and growth. 3.2 Response of the end-user. 3.3 Tunnel operator. Small-scale tests were performed to evaluate the new sys- tems with regard to reliability, accuracy, fire resistance, and 3.4 Emergency response teams. so forth. WP3 Objectives: WP2. (78) WP 2 aims primarily at developing cost-efficient Knowledge will be collected on the design and safety mitigation measures when a fire occurs in a tunnel. The focus measures in current European tunnels. of the work package is therefore an existing and innovative This task focuses on how information is presented, mitigating system. In support of this objective, it aims at how long it takes before tunnel users actually under- improving the necessary evaluation tools and at providing stand the situation (depending on specific scenario and innovative new tools where appropriate. Specifically envis- the information provided), and how they choose their aged tools are the mathematical models and the appropriate escape route. design scenarios that enable the prediction of hazard condi- This task will focus on an analysis of the task of the tions. The appropriate design shall be based on statistical data operator: how operators gain information, what makes and laboratory-scale tests. By providing better knowledge them miss some incidents, how the operators come to about the fire and explosion hazards involved, design fire sce- a decision, what way can they be supported, how the narios and acceptance criteria were to be developed. operators handle the occurrence of several incidents within a short period of time, and how the operators WP2 Technical tasks: communicate with the emergency rescue teams. 2.1 Development of realistic design scenarios 2.2 Define acceptance criteria (79). It seems important to discuss some results of this work 2.3 Evaluation of existing tunnels and current technology group for the benefits of agencies and operators. Simulta- (80). neous management of the problem is required in order to 2.4 Develop new innovative technologies (81). guarantee effective and on-time intervention of operators. 2.5 Engineering guidance and implementation (82, 83). The response teams get their information from the tunnel operator (or from the individual tunnel users) and have to WP2 Objectives: form an idea of the seriousness of the incident, the actions To provide design fires. Design fires will be used to mea- they have to take, the number of people that have to be sure the efficiency of all mitigation systems. Acceptance involved, followed by having to instruct their team mem- criteria for fire effluence in the tunnel shall be suggested to provide a necessary level of safety to be achieved by bers to work together. Furthermore, the tunnel operators mitigation technologies. may also help the emergency response teams by providing Establish knowledge about the performance of current proper information. technologies and to provide a path for development and verification for innovative technologies. The tunnel operator has an important role to react to a To improve and to verify the efficiency of innovative tunnel incident in a timely manner. The operator needs to fire mitigation systems in tunnels, both as stand alone stand-by in order to detect any incidents happening, to decide systems and in combinations with other systems. Focus what the proper action to take is, and needs to provide other shall be given to cost-efficiency. people with information (road users, emergency services, other Identify parameters affecting the effect of mitigation and operators, and so forth). The role of the operator is extremely to provide guidance on how to design a reliable mitiga- important (overview of the situation, possibilities to commu- tion system and to predict the resulting achievements. nicate to several services, and so forth).

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154 In the UPTUN project, an analysis was done of operator Too many incoming signals, not all of which are rele- tasks and bottlenecks based on literature reviews, a Dutch tun- vant at this time (related to overload). nel safety review, and operators interviews. The tasks identified Absence of or insufficient coordinated procedures were: between operators and rescue services. Monitoring the traffic flow and situation in the tunnel Absence of adequate incident evaluating and registra- (and vicinity) using cameras, sensor readings, and com- tion procedures. munication equipment. Constant vigilance was required. Mistake in incident is not evaluated or registered due to Preparation for effect reduction: education, training, fear for career consequences. exercises. Fast and correct detection of any event or disturbance After the tasks and bottlenecks were identified, the next likely to escalate into an incident. step was to find solutions for the most important bottlenecks Closing the tunnel; switching equipment to "emergency and designing an improvement strategy. Using a prioritized mode" (lights, ventilation, speed limits, escape doors, list of bottlenecks and general methods for influencing opera- and so forth). tor behavior generates possible solutions for the most impor- Alerting other operators (where applicable), rescue ser- tant bottlenecks. Possible solutions can be found in terms of: vices, and tunnel users (instructing them for escape if Recruitment (assess the proper criteria). necessary). Training and exercise (to improve skills, but also to test Communicating with tunnel users to help them escape the affectivity of procedures). and to help them assist others or correct the situation Personnel and organization (number of people present, (such as, extinguishing a small fire). working method with time schedules and organiza- From the control room, assisting the rescue services in tional culture). their rescue operation. Task support (such as procedures and guidelines). Control room and interface design (technical tools, such Evaluating and registering the incident. as one button to indicate a major accident, good tools to instruct the tunnel users). The main factors that have a substantial effect on task per- formance and mental effort of the operator are: WP4. The objectives are: To optimize the thermal and structural behavior of all tun- 1. Percentage time occupied: the percentage of available nel components designed for active and passive safety. time that the operator is occupied with his or her tasks. To increase the robustness and load bearing capacity The higher this percentage is, the higher the cognitive under accidental conditions. load. To assess the performance of the integral tunnel structure 2. Level of information processing: relates to the com- in all fire phase conditions: from ignition, through plexity of tasks. growth to the fully developed stage and the decay period. 3. Number of task-set switches: refers to the number of To achieve a robust working/functioning complete sys- switches the operator has to make between different tem, including the effects of fire temperatures. task-sets. The more switches, the higher the cognitive To reduce and limit non-operational time and repair load. retrofitting work. To evaluate existing technology with main emphasis on The operator overload can occur when the operator does cost-benefit (including maintenance). not have enough time to finish the tasks, the operator tasks To establish safer design and to evaluate recommenda- are too complicated, or the operator has to perform too many tions for optimal tunnel systems. tasks at the same time (or a combination of any of these elements). An underload, just as overload, may lead to sub- WP4 Technical tasks: optimal performance. Ideally, the task load matches the oper- 4.1 Structural elements functional performance, and load ator's mental capacity in a certain task setting. Other identified bearing capacity. bottlenecks (although this list does not include all bottlenecks 4.2 Improving components functional capacity. identified) were: 4.3 Innovative damage assessment and repair and recovery Vigilance problems during long periods of normal oper- and retrofitting. ation (related to underload). 4.4 Proposal of innovative solutions. Unclear allocation of responsibilities and authority to 4.5 Safety levels criteria evaluation/engineering guidance personnel. and implementation. Insufficient skills due to lack of practice exercises, espe- cially with the rescue services. WP4 Objectives: Overdue, incorrect, or incomplete detection of incident It is necessary to achieve better understanding and gain due to the combination of suboptimal cognitive load more insight in structural performance of concrete load- and suboptimal detection of risk factors in tunnel. bearing elements under fire emergency conditions

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155 To develop new mitigating measures. for both people and the infrastructure. An assessment To avoid or limit structural damage to an acceptable of fire risk profiles for a tunnel before and after upgrad- level. ing will then allow the socio-economic impact to be To provide fast repair methods. evaluated. To demonstrate the practical utility of the evaluating By means of numerical analyses and laboratory fire tests, and upgrading procedure by applying it to an existing data are established for all individual elements regarding tunnel. its resistance and functionality as a function of its exposure To demonstrate the cost-effectiveness of the UPTUN time. These data help to point out possible improvements to project and assess its wider socio-economic impact. currently available elements and to make recommendations for designing new ones. The different element with the best WP6. Objectives: characteristics is identified and, if appropriate, proposed for Demonstrate experimentally the effectiveness of the use in upgrading tunnels. innovative fire safety features in combination. Demonstrate, with before and after tests, that the in- Therefore, it is essential to: novative upgrading measures proposed in this project Assess the damage level very quickly. provide major improvements in fire safety when Propose and apply adequate repair and recovery methods. compared with the existing tunnels situation without upgrading. The rather hostile tunnel environment, in combination Provide feedback to work packages 1 to 4 in terms of with the desired limited non-operational time, requires devel- the interaction of their individual features with the fea- opment of innovative FAST and ACCURATE damage assess- tures developed in other work packages. ment techniques. For tunnels where current system design Validate the theoretical model developed in work is not suitable, alternative innovative solutions shall be sug- package 5. gested. Alternative optimized configurations and advanced Make recommendations for upgrading based on actual technological engineering solutions shall be studied and ver- testing. ified. Indications on how to achieve reductions and/or elimi- nation of explosive spalling were given. WP6 Technical tasks: 6.1 Framework for the demonstrations WP5. This task encapsulates the essence of the UPTUN 6.2 Demonstration before upgrading project; namely, the evaluation and upgrading of the safety 6.3 Demonstration after upgrading level of existing tunnels consistent with the safety levels 6.4 Analysis of results and validation of theoretical model established in this project as a whole. In that respect, this work package brings together all the various strands from WP6 Objectives: the other work packages and, therefore, inevitably requires To optimally design full-scale tests that show interaction input from and collaboration with all the partners of this major project. and validate the models developed in the previous work package. WP5 Technical tasks: To set a reference for identifying the positive effect of the 5.1 Identifying safety features. innovative measures or innovative combination of mea- 5.2 Setting criteria for evaluating safety levels and systems sures by determining the safety level of non-upgraded failure. tunnel(s). 5.3 Holistic evaluation and upgrading of existing tunnels To investigate the innovative measures in realistic con- safety. figurations and combinations to determine their actual 5.4 Example: Upgrading of an existing tunnel. beneficial effect. To gather validation information for 5.5 Financial, socio-economic, macroeconomic, and envi- the models developed in the other work packages. ronmental evaluation of upgrading tunnels to improve To provide validation information for the theoretical fire safety. models. To make recommendations for large scale data gathering and analyses. To provide adequate promo- WP5 Objectives: tional and educational material. To ensure that the safety features are clearly identified in a rational manner. Furthermore, since not all aspects can be foreseen from To ensure that the evaluation criteria are clearly defined the start of the project, nor can all problems be solved within in a rational manner taking into consideration the inter- UPTUN, strong links have been established with existing action between the different safety features. relevant research projects on the national and international To develop a procedure called "UPGRADE" for eval- level, such as the European projects DARTS, FIT, and SafeT. uating and upgrading the safety level of a tunnel as a WP 7 Promotion, dissemination, education/training, and whole and to present the output in terms of risk profiles socio-economic impact (WPL STUVA; D)

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156 D.2.6 FIT (8 ) In Technical Report Part 2, Fire Safe Design, a compilation of relevant guidelines, regulations, standards, or current best Technical Report Part 1, Design Fire Scenarios (76), de- practices from European member states (and major tunneling scribes recommendations on design fire scenarios for road, countries, like Japan) are given. The analysis is focused on all rail, and metro tunnels. Design fires are to cover different fire safety elements regarding tunnels and is classified accord- relevant scenarios, such as design fires in regard to the ing to the transport nature: road, rail, and metro. The three evacuation of people and to ventilation purposes, as well as sections in the report present the collected guidelines and in regard to the structural loads, which are presented and regulations, their analytical abstract, and table of contents. recommended. The report collects data from different coun- About 50 safety measures are presented and compared related tries, including Germany, France, Italy, and the U.K., as to structural measures (19), safety equipment (36), and struc- well as international organizations, such as PIARC, ITA, ture and equipment with response to fire (3). For each type of measure the impact on safety is presented with a synthesis and and UPTUN. It also incorporates from the experiences in a detailed comparison of the comprehensive list of safety individual tunnels, including Mont Blanc, Tauern, Nihon- measures. zaka, Caldecott, and Pfnder. The report includes basic prin- ciples of design fires, tunnel fire statistics, and impacts of The occurrence of a fire in a tunnel provokes a need for fires and smoke in tunnels on people, equipment and struc- responses from tunnel users, the operators, and the emergency ture. The data are analyzed and different sets of data are services personnel. Technical Report Part 3, Fire Response compared to ascertain the degree of confidence attributed to Management, presents the best practices to ensure a high level the information. of safety.