RABT

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ROAD AND TRANSPORTATION RESEARCH ASSOCIATION

WORKING GROUP TRAFFIC ROUTING AND ROAD SAFETY

Regulations

for the

equipment and operation

of road tunnels

Edition 2006

Reproduced with permission of the Road and Transportation Research Association

publishing company (FGSV-Verlag). Authoritative for the application of the Road and

Transportation Research Association regulations shall be the version with the latest date

of issue, which is available at the Road and Transportation Research Association

publishing company: FGSV-Verlag, Wesselinger Staße 17, 50999 Köln (Germany).

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Federal Ministry for Traffic, Bonn, 27 April 2006 Building and Urban Affairs

S 18/7195.10/00-490187

General circular road construction no. 10/2006

Domain 05.9: tunnel equipment

Chief road construction authorities of the states Chief state authorities for road traffic regulations and traffic police

For the information of:

Federal Highway Research Institute Federal Audit Office

DEGES: Deutsche Einheit

Fernstraßenplanungs- und -bau GmbH

Re: Operational equipment of road tunnels

- Implementation of Directive 2004/54/EC of the European Parliament and Council dated 29 April 2004 about minimum requirements of the safety of tunnels in the trans-European road network into national law

- Regulations for the equipment and operation of road tunnels (RABT), edition 2006

Ref: Operational equipment of road tunnels

a) Meeting bridge building and construction engineering on 20/21 March 2006 b) Meeting bridge building and construction engineering on 9/10 November 2005 c) My general circular road construction no. 17/2003 dated 24 March 2003

– S 27/38.75.50/23 Va 2003 –

d) My general circular road construction no. 19/2005 dated 18 August 2005 – S 18/38.75.50/51 Va 2005 –

e) My letter dated 2 June 1999 – S 28/38.50.00-15/57 Va 99

A. In the context of the heavy fire accidents in some road tunnels of the Alpine states, possible measures for

increasing the safety of users were examined in detail in the past years. In this context, the EU commission (COM) issued the “Directive 2004/54/EC of the European Parliament and of the council of 29 April 2004 on minimum safety requirements for tunnels in the trans-European road network” (EC tunnel directive). For the required national implementation, the “Regulations for the equipment and operation of road tunnels” (RABT) were updated by the Road and Transportation Research Association in consultation with me and the chief road construction authorities; they now are available in the 2006 edition (Appendix 1).

Additions to the RABTs were basically made in accordance with the requirements of the EC tunnel directive; these include:

- the institutions of the EC tunnel directive: • administration,

• tunnel manager, • safety officer and

• examination centre as well as

- the traffic-related legal and technical regulations, - the reporting system,

- the safety documentation, - the risk analysis,

- the constructional and operational measures.

Among other things, an essential aspect of the new regulations is the improvement of the possibilities for the users to save themselves in case of an accident. For this, it is especially important that the relating safety

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equipment is designed and set up as uniformly as possible. The regulations for this according to ARS 19/2005, which have already been issued, were included in the RABTs, edition 2006.

In this context, I would also like to point out recital no. 25 to the EC tunnel directive, in which the member states are asked to provide comparable safety levels for road tunnels in their sovereign territories that are not part of the trans-European road network (TERN) and thus are not included in the scope of application of this directive.

B. In addition, I would like to point out the following:

1. Please provide me soon with the names and addresses of the administration authorities listed in item 1.1 of

the RABTs, edition 2006, including a list of the tunnels in the respective areas of responsibility, classified according to the type of road (TERN, BAB, B) in accordance with Appendix 2.

For processing, it is possible to directly request Appendix 2 as an Excel file via the e-mail address: [email protected]

Due to the tight time schedule, I would also like to ask you to send me the names and addresses of the administrative authorities as well as the filled in tables in advance via e-mail to the address specified above.

2. For road tunnels in the course of federal trunk roads that cross state borders or borders of other regional

authorities, administrative agreements must be made between the respectively responsible states or regional authorities involved, which include details on cooperation and the respective responsibilities.

For road tunnels that lead from the territory of the Federal Republic of Germany into another EU member state, one administrative authority each can either be selected by the Federal Republic of Germany and the other EU member state or the two states can name a common authority (see art. 4, para. 3, clause 2 EC tunnel directive). If one authority each is selected by every state, it is necessary to determine details on the cooperation of the two authorities in a bilateral agreement. If the two road administrations decide to set up a common authority for the road tunnel, it is necessary to make an agreement under international law (responsibility Federation), since the common administrative authority will have sovereign rights (e.g. option of making administrative decisions) that will affect both states.

The bilateral organisation plan for emergency cases must be agreed upon with the responsible authority of the other EU member state and be agreed upon on an administrative level.

3. The administrative authorities must evaluate the

- road tunnels not yet authorised for general traffic on 30 April 2006 - road tunnels authorised for general traffic on 30 April 2006

regarding their compliance with the requirements of the RABTs, edition 2006, under the particular consideration of the safety documentation in compliance with the RABTs, edition 2006, Section 1.1.5 and on the basis of an inspection.

The tests already performed in the context of the retrofitting programme can be used for this and must be supplemented where necessary. The required retrofitting measures must be included into the existing retrofitting schedule.

The respective agreements on retrofitting federal trunk road tunnels outside the TERN will be made with you in the context of the retrofitting programme.

4. According to Article 11 of the EC tunnel directive, the member states must present the COM with a report

explaining their plans regarding the consideration of the requirements of the EC tunnel directive as well as the planned measures and comment on the consequences if necessary, which result from opening and closing the most important tunnel access roads.

For tunnels belonging to the TERN, the results of the evaluation according to item B3 must be presented to the Federal Ministry for Traffic, Building and Urban Affairs (BMVBS) by the administrative authorities by 1 August

2006 in the form of a report.

The tests performed in the context of the retrofitting programme can be used for this and must be extended where necessary. The required retrofitting measures must be included into the existing retrofitting schedule. The retrofitting schedule must also be presented to me.

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5. In the future, the administrative authorities must make reports on fires and accidents in tunnels and their

number and causes in accordance with the RABTs, edition 2006, Section 1.1.9.

These reports must be presented to me for the first time for all tunnels in the area of federal trunk roads for the reporting period of 1 May 2006 to 31 December 2007 by 31 March 2008. After that, the reports always must be presented by 31 March of every year.

A respective report form is being generated at present by the BASt and will be provided to you shortly.

In addition, I would ask you to immediately inform me about accidents and fires that occurred with loss of life in the area of federal trunk roads independently of the previously named reporting obligation.

6. In order to use innovative safety equipment or safety procedures in accordance with RABT, edition 2006, Section 1.1.8, it is necessary to seek the authorisation for federal trunk roads in individual cases at the BMVBS; for tunnels in the area of the TERN, it is also necessary to obtain an authorisation by the COM. For this, I ask the COM to make timely agreements with me.

7. The administrative authorities must organise regular informational campaigns on issues of tunnel safety. These informational campaigns include the correct behaviour of road users when approaching and driving through tunnels, particularly in case of traffic jams, accidents and fires. The tunnel users must be informed about the existing safety equipment and the correct behaviour in the tunnel at appropriate places (e.g. at rest areas before tunnels, at the entrances of tunnels at which the traffic is stopped or via Internet).

Among other things, a corresponding leaflet and a brochure as well as information are provided on the homepage of the BMVBS under

http://www.bmvbs.de/Verkehr/Strasse-,1452/Sicherheit-in-Strassentunneln.htm on this subject.

C. Furthermore, the following must be considered when implementing the regulations:

1. Please consider the following in order to ensure a clear implementation of the requirements of the EC tunnel directive regarding the selection of the cross section for tunnels in the planning phase in the area of the TERN: - If a 15-year forecast for tunnels in the area of the TERN shows that the traffic volume will exceed 20,000 veh/24 h, a double tunnel with one-way traffic must be provided for the point in time at which this value is exceeded.

- The determination of the cross section of tunnels in the context of multiple-lane carriageways is made in accordance with the “procedure for selecting road cross sections in tunnels” (ARS 6/2000).

2. For tunnels on federal trunk roads outside the TERN, the number of tunnel tubes and the cross sections must be specified in compliance with RAS-Q in combination with ARS 6/2000.

For the dimensioning, the dimension parameters relevant up to now must be used aside the traffic volume. 3. In accordance with RABT, edition 2006, Section 0.5, a risk analysis is required in certain cases to ensure the

safety in tunnels. In this context, the EC tunnel directive, Article 13, demands that the member states ensure a precise, exactly defined, best-practice method for risk analysis on a national level to achieve the required safety level in cases for which the relevant safety regulations of the RABTs, edition 2006, cannot be fulfilled for personal security without additional measures. For this, the BASt already requested a corresponding examination in 2005 on my orders. I will inform you immediately as soon as applicable results are provided (first results probably in 2007).

4. The regulation stating that a maximum permitted speed of 80 km/h must not be exceeded as an assessment basis still applies. A general raising of the speed limit to 100 km/h, for example, cannot be justified due to the doubling or tripling of costs that would be imposed on the federal budget for illumination and the annual operational costs for the illumination.

However, in some justified cases it is possible to set a maximum permitted speed of 100 km/h in road tunnels with one-way traffic and hard shoulder if:

- this is justifiable due to the decreasing outside brightness in the course of the day from a light-related point of view (measuring value acquisition in 20° field), and the maximum permitted speed can already be displayed prior to entry into the tunnel with variable-message signs in the context of the light-related control of the illumination system depending on the outside brightness.

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- the immission situation at the tunnel portals makes an increased speed of the cars possible without ventilation-related additional measures (e.g. due to the increase of the NOx values by about 30%) despite the

legal limit values that must be observed (according to EC directive).

Under the above named conditions, it is possible to assume that the traffic safety will not be affected by a temporary increase in the maximum permitted speed in the individual case.

5. In the context of construction and maintenance work on individual lanes in the tunnel, the respective lanes must always be closed before entry into the tunnel due to the generally short lengths of the tunnels. This applies for tunnel tubes that are operated with two-way traffic as well as tunnels with one-way traffic. According to the regulations, a closure inside the tunnel by means of (variable-) message signs is not intended.

6. Please perform fire tests for the purpose of checking the tunnel equipment and performing exercises according to RABT, edition 2006, Sections 4 and 6, at least for tunnels with mechanical ventilation.

D. Please introduce the above named regulations for the business area of federal trunk roads with respect to the EC tunnel directive. Please send me a copy of your introductory letter. In so far as these regulations contain rules for the road traffic authorities that bind or limit their judgment, these are made in accordance with the chief road traffic authorities.

For the benefit of a uniform handling, I recommend to also introduce the edited regulations for the tunnels in your area of responsibility. The RABTs, edition 2003, shall no longer be used in the future.

I withdraw the general circulars no. 17/2003 and no. 19/2005 as well as my letter dated 2 June 1999-S 28/38.50.00-15/57 Va 1999.

The RABTs, edition 2006, can be obtained from FGSV Verlag, Wesselinger Straße 17, 50999 Köln.

P.p.

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BMVBS ARS no. 10/2006

Appendix 2 Specification of the administrative authorities

with specification of: - name, - address,

as well as the tunnel belonging to the individual authorities, sorted according to: - tunnels on federal motorways within the TERN,

- tunnels on federal roads within the TERN, - tunnels on federal motorways outside the TERN, - tunnels on federal roads outside the TERN, each with the following specifications:

- location (name of place), - road (numbering),

- status (in operation, under construction, in planning), - type of traffic (one-way/two-way traffic),

- number of tubes, - cross section, - total number of lanes, - tunnel length, - total tube length,

- longitudinal inclination, - traffic volume,

- proportion of HGVs - speed limit,

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ROAD AND TRANSPORTATION RESEARCH ASSOCIATION

WORKING GROUP TRAFFIC ROUTING AND ROAD SAFETY

Regulations

for the

equipment and operation

of road tunnels

RABT

Edition 2006

Reproduced with permission of the Road and Transportation Research Association

publishing company (FGSV-Verlag). Authoritative for the application of the Road and

Transportation Research Association regulations shall be the version with the latest date

of issue, which is available at the Road and Transportation Research Association

publishing company: FGSV-Verlag, Wesselinger Staße 17, 50999 Köln (Germany).

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WORKING GROUP TRAFFIC ROUTING AND ROAD SAFETY

Working committee equipment and operation of road tunnels

Head: Prof. Dr.-Ing. Wolfgang Baltzer, Heidelberg Staff members: Dr.-Ing. Friedhelm Blennemann, Cologne

Dipl.-Ing. Alfred Dürr, Weinstadt-Endersbach BR Dipl.-Ing. Rainer Fondel, Wiesbaden Dr.-Ing. Kurt Herzke, Wedel

Ltd. RBDir. Dipl.-Ing. Herbert Hölters, Wesel Ltd. BDir. Dipl.-Ing. Karl-Heinz Krüger, Hamburg Dr.-Ing. Peter Kündig, Zürich

OAR Dipl.-Ing. Jörg Luckmann, Bonn

Dipl.-Ing. Otfried Matthes, Hamburg

Dipl.-Ing. Georg Mayer, Aachen OBR Dipl.-Ing. Ingrid Ortlepp, Erfurt

Dipl.-Ing. Werner Riepe, Heidelberg

BOR Dipl.-Ing. Martin Schiermeier, Munich

Dr.-Ing. Jörg Schreyer, Cologne

BR z. A. Dipl.-Ing. Christof Sistenich, Bergisch Gladbach Ltd. Branddir. Dipl.-Ing. Werner Thon, Hamburg

OBR Dipl.-Ing. (FH) Wolfgang Tress, Stuttgart BDir. Dipl.-Ing. Heinz Unruh, Munich

Section 2.4 of the RABTs 2003 was adopted as Section 5 without changes in content into the RABTs 2006.

It was edited by the

Working committee: Traffic control on roads outside towns Working group: Traffic-related technical equipment in tunnels

Dipl.-Ing. Thomas Gerlach, Aachen Dipl.-Ing. Klaus Hahn, Karlsruhe Dipl.-Ing. Torsten Klein, Berlin Dipl.-Ing. Rainer Lehmann, Cologne

Dipl.-Ing. Kai Lorenz, Berlin

BDir. Dipl.-Ing. Hartmut Oßwald, Stuttgart

ORR Dipl.-Ing. Sylvia Piszczek, Bergisch Gladbach BOR Dipl.-Ing. Frank Süsser, Bonn

Dipl.-Ing. Stefan Trupat, Bergisch Gladbach Dipl.-Ing. Sabine Vogler, Hamburg

Preliminary note

The “Regulations for the equipment and operation of road tunnels” were first set up in the Road and Transport Research Association by the working committee “Equipment and operation of road tunnels” in 1985. In the years 1994 and 2003, new editions were published.

The revised version of the RABTs 2003 was necessary due to the national implementation of the “Directive 2004/54/EC on minimum safety requirements of tunnels in the trans-European road network” (EU tunnel directive) of 29 April 2004.

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0. Introduction

0.1 Content

The “Regulations for the equipment and operation of road tunnels” (RABT) contain principles, information and criteria for planning the equipment of road tunnels and their operation.

They are divided into a text part and appendixes. The appendixes contain comments, background information, examples and calculating methods contributing to the understanding of the text part and providing instructions for planning.

The regulations only cover constructional issues in so far as these are directly connected to the equipment and operation. Regulations on the constructional design of road tunnels and their equipment are included in the “Additional technical terms of contract and regulations for civil engineering works, Part 5: Tunnel construction, Section 4: Operational equipment of road tunnels” [1].

0.2 Purpose

The measures described in the RABTs are mostly used to ensure safe traffic routing, avoid critical events, protect the tunnel users and the environment as well as to support the emergency services1 in case of fires, accidents and breakdowns.

They are intended to lead to a uniform equipment of tunnels, designed according to standardised principles and criteria, and to enable safe operation at a quality adapted to the respective traffic and local conditions under consideration of cost effectiveness. The elements of the technical equipment must be designed and installed in a robust, secure and maintenance-friendly way. Communicated information must be clear. In the case of irregularities, the technical equipment supports tunnel users at rescuing themselves and security staff at their work. An element of risk still remains and cannot be ruled out generally even if the technical equipment and monitoring are provided to the best possible extent, and thus must be accepted. The regulations specified in the RABTs cannot replace the specialist technical examination and planning for every individual case. Deviations from the regulations must be reasoned; the safety standards described in these regulations still must be observed here. In the case of already existing tunnels, Section 0.5 must be observed.

1_{Emergency services in accordance with these regulations are all}

local – public and private – services or tunnel staff providing aid in the case of an incident, including police, fire brigade and medical services.

0.3 Validity

The RABTs are valid for all tunnels intended for vehicle traffic from a covered length of 80 m.

In addition, the regulations apply for existing tunnels that are longer than 400 m and, upon testing of appropriateness of the measures to be taken, also for tunnels of between 80 m and 400 m in length.

Partially covered above-ground or underground roads, above-ground noise barriers of roads, cross-road constructions with other cross-roads as well as gallery constructions are also regarded as road tunnels. If cyclists and pedestrians are also supposed to use tunnels in addition to vehicle traffic, additional requirements must be met.

0.4 Overall safety concept

The regulations are no inflexible standard. For using them, it is necessary to consider the various different requirements resulting from traffic quality, safety and cost-effectiveness as well as from the environmental conditions in a well-balanced way and include them into an overall safety concept. On the basis of a typical damage scenario that must be determined (accident, fire, HGV, car etc.), this concept must particularly contain statements on damage prevention, damage reporting, self-rescue and third-party rescue of persons as well as on assistance and fire fighting.

Among others, the following parameters influence safety:

- tunnel length - number of tunnel tubes - number of lanes - lane widths

- cross section geometry - underground entrances and exits - road layout

- construction type - one-way or two-way traffic

- traffic volume per tunnel tube (including the temporary distribution)

- risk of daily or seasonal traffic jams - access time of emergency services - proportion of HGV traffic

- existence, proportion and kind of hazardous goods traffic

- characteristics of access roads - speed-related aspects

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The constructional measures resulting from the overall safety examination must be part of the planning approval documents.

0.5 Risk analysis

If a tunnel longer than 400 m has a special characteristic regarding the previously named parameters, it is necessary to perform a risk analysis in order to determine whether additional measures and/or equipment, which lie outside the RABT standard, are required to ensure safety in the tunnel. If constructional requirements for existing tunnels lead to inappropriately high costs or if they cannot be implemented, it must be checked in what way they can be compensated for by means of other measures. The administrative authority (Section 1.1.1) can accept the implementation of risk-lowering measures as an alternative to the constructional requirements if these measures lead to an equally high or higher safety level. Their effectiveness is proved on the basis of a risk analysis. In a risk

analysis, the risks for a certain tunnel are examined under consideration of all safety-relevant planning-related and traffic-planning-related factors, while all parameters mentioned above must be considered. Furthermore, the following must be proven by means of a risk analysis:

- permissibility of a longitudinal ventilation, see Section 4.3.3

- permissibility of hazardous goods transports, see Section 9.

Risk analyses are performed by an institution that is functionally independent from the tunnel manager according to Section 1.1.2. The content and the results of the risk analysis must be included in the safety documentation (see Section 1.1.5), which is presented to the administrative authority.

Damage scenarios, empirical assessments as well as statistically acquired accident data are included in the examination.

1. Organisation and operation

1.1 Organisation

For tunnels longer than 400 m, the organisational forms and measures for planning, construction and operation are required for ensuring the required safety level permanently.

1.1.1 Administrative authority

The road building agency names the administrative authority. The administrative authority2 must make sure that all requirements relating to the safety of a tunnel are met and issues the necessary rules in order to ensure that the regulations are observed. The administrative authorities put tunnels into operation in accordance with Section 1.1.6.

The administrative authority can interrupt or restrict tunnel operation if the safety requirements are not met. It specifies the conditions under which the tunnel can be operated again.

It ensures that the following tasks are fulfilled:

a) regular tests and inspections of the tunnel equipment as well as the specification of thus related safety requirements

b) introduction of organisational and operational processes including the plans for action in case of incidents

2_{Note: The administrative authorities are not the traffic authorities}

responsible for the setting up of road signs. However, this must be included if necessary.

c) determination of the procedure for immediate closure of a tunnel in case of an incident

d) implementation of the required risk-lowering measures.

Only one administrative authority is responsible for each tunnel; however, an administrative authority can be responsible for numerous tunnels.

1.1.2 Tunnel manager

For every tunnel in planning, under construction or in operation, the administrative authority specifies a public or private institution as tunnel manager that is responsible for the tunnel management in the respective phase. These tasks can be performed by the administrative authority itself.

The tunnel manager writes a report about all significant disturbances and accidents that occur in the tunnel. The report is communicated to the safety official in compliance with Section 1.1.3, the administrative authority and the emergency services within one month at the latest.

If a supplemental examination report is written, in which the circumstances of the above named disturbance or accident are analysed or the thus resulting conclusions are explained, the tunnel manager forwards this report to the safety official, the administrative authority and the emergency services one month after he/she has received it at the latest.

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1.1.3 Safety official

The tunnel manager appoints a safety official for every tunnel, who must be accepted beforehand by the administrative authority and who coordinates all preventative and safety measures in order to ensure the safety of the users and the operating staff. The safety official can be an employee of the tunnel staff, the emergency services or a person employed externally. The official is independent regarding all issues relating to the safety of road tunnels and is not bound to any instructions in this area. Safety officials can take on their tasks in several tunnels of a region. Safety officials take on the following tasks and functions:

a) they ensure the coordination with the emergency services and help with the composition of operational procedures

b) they help with the planning, implementing and evaluating of operations in case of events

c) they help with the design of safety programmes and the determination of specifications for constructional devices, equipment and operation for new tunnels as well as for the reconstruction of existing tunnels

d) they make sure that the operating staff and the emergency services are trained and they help with the organisation of exercises that are held regularly

e) they provide specialist advice regarding the acceptance of constructional devices, the equipment and operation of tunnels

f) they make sure that the constructional devices and the equipment of tunnels are maintained and repaired

g) they help with evaluating significant disturbances or accidents.

1.1.4 Examination department

The administrative authority must ensure that inspections, evaluations and tests are performed by examination departments. The examination department must provide a high level of specialist know-how and have high-quality methods available; it must be functionally independent of the tunnel manager. These tasks can be performed by the administrative authority itself.

1.1.5 Safety documentation

Prior to the start of construction works, the tunnel managers compose the safety documentation, which they update regularly, and the safety official in. The tunnel managers provide the safety documentation together with the statement of the safety officials and/or the examination department, if available, to the administrative authority.

The tunnel managers compose safety documentation for every tunnel they are responsible for, which they

update regularly. They forward a copy of this safety documentation to the safety officials.

The safety documentation contains a description of the preventative and securing measures that are necessary under consideration of persons with limited mobility and handicapped persons, the type of road, the total design of the construction, its surroundings, the type of traffic and the requirements for action of the emergency services to ensure the safety of the users.

a) For a tunnel in planning, the safety documentation contains the following components in particular: - the documents required to display the overall safety

concept according to Section 0.4 as well as the risk analysis according to 0.5, if necessary

- specialist safety reports by a specialist in this field or a corresponding organisation, for example, the examination department.

b) For a tunnel in the phase of opening, the safety documentation contains the following in addition to the components required for the planning phase: - a description of the organisation responsible for

ensuring the operation and maintenance of the tunnel, the human and material resources and the instructions specified by the tunnel managers - the alarm and danger prevention plans that must be

set up according to Section 1.2.3

- a description of the system for acquiring and analysing significant disturbances and accidents. c) For a tunnel in operation, the safety documentation contains the following in addition to the components for the phase of opening:

- a report with an analysis on significant disturbances and accidents that occurred since these regulations came into effect

- a list of the performed safety exercises and an analysis of the conclusions derived from these exercises.

1.1.6 Commissioning 1.1.6.1 Opening

The first opening of a tunnel for general traffic (commissioning) is subject to the authorisation by the administrative authority (acceptance), for which the procedure described in the following applies.

The tunnel managers provide the safety documentation according to Section 1.1.5 to the safety officials, who comment on the opening of the tunnel for general traffic.

The tunnel managers forward this safety documentation to the administrative authority together with the statement of the safety official. The administrative authority decides whether it permits the opening of the tunnel for general traffic, permits

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the opening with restrictions or does not permit the opening and informs the tunnel manager and safety official about the decision. The emergency services obtain a copy of this decision.

1.1.6.2 Reopening

The procedure according to Section 1.1.6.1 also applies for reopening a tunnel for general traffic after extensive constructional or operational changes or important reconstruction work in the tunnel, which can result in significant changes to components of the safety documentation.

1.1.6.3 Changes

For all important changes regarding construction, equipment or operation, which can affect parts of the safety documentation significantly, the tunnel managers apply for a new authorisation for opening the tunnel according to the procedure described in Section 1.1.6.1.

The tunnel managers inform the safety officials about all other constructional and operational changes. In addition, the tunnel manager provides a copy of the documentation to the safety official prior to changing works, in which the suggestions are explained in detail.

The safety official checks the effects of the change and provides his/her statement to the tunnel manager; the tunnel manager forwards a copy of this statement to the administrative authority and the emergency services.

1.1.7 Recurring inspections

The administrative authority makes sure that the examination department performs regular inspections in order to ensure that all tunnels included in these regulations comply with the therein described stipulations.

No more than six years may lie between two successive inspections of a tunnel.

If the administrative authority detects that a tunnel does not comply with the stipulations of these regulations on the basis of this report, it tells the tunnel manager and the safety official that it is necessary to take measures for increasing the safety in the tunnel. The administrative authority specifies the conditions for continued tunnel operation or for the reopening of the tunnel, which are valid until the measures for eliminating the deficits have been applied as well as additional restrictions or conditions serving for this purpose.

If the measures for eliminating the deficits include significant constructional or operational changes, the tunnel must undergo another procedure for the authorisation of its opening according to Section 1.1.6 as soon as these measures are taken.

1.1.8 Exceptions for innovative technology

The administrative authority can allow exceptions from the requirements of these regulations on request of the tunnel manager in order to allow the installation and use of innovative safety devices or use of innovative safety procedures that offer an equal or higher level of safety in comparison to the current level of technology, which is the basis for these regulations.

1.1.9 Data acquisition for reports

The administrative authority must write annual reports on fires and accidents in tunnels as well as on their frequency and causes. In this report, the incidents must be evaluated and specifications must be made on the actual significance and effectiveness of safety devices and measures. The reports must be provided to the responsible federal ministry.

1.2 Monitoring, control and maintenance

The following is necessary for the operation and maintenance of a tunnel:

- Monitoring, controlling and securing of the traffic in normal, incident and emergency cases

- Monitoring, controlling and supervising of the technical installations in normal, incident and emergency cases

- Cleaning of the installations and the construction - Maintenance, repairing and renewing of the

technical installations

- Organisation plans for emergency cases (breakdowns, accidents, fire).

1.2.1 Tunnel monitoring

The tunnel monitoring, control, error elimination and maintenance must be transferred to an operating centre (e.g. motorway maintenance, road maintenance). From there, it must at least be possible to control the ventilation and illumination, close down the tunnel as well as inform and warn the tunnel users via loudspeakers and traffic message channels. Individual work areas can be transferred in part or entirely to third parties, e.g. maintenance companies. The administrative authority must check which organisation is the most appropriate in the individual case.

For tunnels longer than 400 m, it must be ensured that the emergency calls and video monitoring are transmitted to a continuously staffed place.

For example, the following organisation options exist for tunnel monitoring:

- Staff in a continuously staffed tunnel control room - Staff in a control centre outside the tunnel, e.g. in

a motorway/road maintenance agency - Staff in a traffic control centre.

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1.2.2 Error elimination and maintenance

Error elimination and maintenance can be performed by technical staff of the responsible institution, by maintenance companies or by both in combination. If the responsible institution has its own technical staff, this should perform the error elimination. This also includes on-call duty. In addition, this staff should perform function checks and the contractual monitoring of the maintenance companies in the context of the maintenance work. Staff-intensive work such as lamp changes and lamp cleaning should always be transferred to maintenance companies. It has proven to be beneficial to award the maintenance for 5 years together with the installation of the technical equipment (with an option for extension). In this way, it is possible to avoid conflicts between maintenance and warranty.

For the maintenance of all parts of the technical equipment, the following must be determined:

- maintenance intervals - type and scope of works - documentation of works.

Specifications are contained in the model contract for the “Maintenance of the technical equipment of road tunnels” [3].

For work that takes place in or next to the traffic area, it is always necessary to provide safety measures in compliance with the “Regulations for securing workplaces on roads” [4].

1.2.3 Organisation for emergency cases

Emergency management is intended to ensure the safety of the persons in the tunnel.

First emergency measures are:

- fast detection and recording of the emergency situation

- triggering or monitoring of the safety devices and systems as well as the traffic-related devices - immediate information of the police, fire brigade

and rescue services according to alarm plans

- information and warning of the persons in danger - execution or start of the evacuation.

The institution responsible for the operation sets up alarm and danger prevention plans. These also must include the needs of handicapped persons. The information paths must be set up in consultation with the police, fire brigade and rescue services.

In agreement with the institution responsible for fire protection, emergency plans for fire brigade use must be set up and updated in accordance with DIN 14095. The emergency plans must be made available to the fire brigade.

The action schemes specified in the alarm and danger prevention plans for the different emergency cases must be checked and exercised by the tunnel manager and the emergency services in cooperation with the safety official regularly for tunnels longer than 400 m.

These exercises should

- be as realistic as possible and correspond with the stipulated incident scenarios,

- provide clear results and

- be performed in such a way that damages to the tunnel are avoided.

- they can also be performed in part and for additional results on a model or in the form of computer simulations.

At least every four years, it is necessary to perform extensive exercises under conditions as realistic as possible. The tunnel is only ordered to be closed if suitable precautions for the diversion of traffic can be made. In the periods between these exercises, partial and/or simulation exercises must be performed. In areas in which several tunnels are located close to each another, the extensive exercise must be performed in at least one of these tunnels.

The safety official and the emergency services assess these exercises together, write a report and make suggestions for possible measures for improvement.

2. Traffic area tunnel

2.1. General

Tunnels are part of a road. The traffic conditions in tunnels thus should generally correspond with those on a road. However, tunnels are special sections of a road, which require high costs for their construction, maintenance and operation. Tunnels have to meet

special requirements of road safety and operational safety. When deciding between the requirements of the quality of the traffic flow as well as the cost-effectiveness, it is necessary and justifiable in many cases to lower the speed compared with the road outside the tunnel. Generally, a speed limit of 80 km/h is recommended.

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2.2 Longitudinal tunnel inclination

In tunnels longer than 400 m, additional and/or stronger measures must be taken for an inclination of over 3% on the basis of a risk analysis for improving safety. An inclination of more than 5% should be avoided.

2.3 Tunnel cross section, unobstructed

area, traffic area

The tunnel cross section depends on the traffic volume and the selected type of construction. The standard cross section must contain dimensions that

make it possible to provide for the equipment such as illumination, ventilation, traffic-related devices and safety devices, generally outside the unobstructed. area. Particularly, devices for ventilation and directions may require an increase in the tunnel cross section. In order to limit the variety of possible cross sections – also for economical reasons – road cross section types in the tunnel are assigned to the standard cross sections of roads outside tunnels. The tunnel cross section must be selected according to the ARS 6/2000, Appendix “Procedure for selecting road cross sections in tunnels” (Figure 1) [5].

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The unobstructed area is that area of the road cross section that must be kept free of fixed obstacles. It consists of the traffic area and the upper and side safety areas. The required cross section area for the unobstructed area results from the traffic purpose of the tunnel. It is derived from the purpose of the respective uncovered area, while the permitted restrictions of the cross section in the area of constructions are considered (RAS-Q [6]).

The total width of the unobstructed area results from the summation of the widths of the safety areas on the sides, the lanes, the shoulder and possible additional shoulders (e.g. hard shoulder). The required height is 4.50 m for vehicle traffic. For economical reasons, the edge lines on the side generally are perpendicular so that it becomes necessary to enlarge the safety area in case of a greater cross slope of the carriageway. For circular cross sections, however, it can be economical to incline the unobstructed area with the cross slope. The edge lines on the side then can be assumed vertically to the carriageway. It is not necessarily required to widen the safety area in these cases. In case of rectangular cross sections, for which the edge lines of the traffic area are applied perpendicularly, high vehicles can extend into the free area which is at least 30 cm wide if the carriageway is inclined towards the wall. For cross slopes q of more than 3.5%, the cross section thus must be broadened in accordance with table 1.

The boundary of the unobstructed area contains areas that are exclusively reserved for traffic (Figure 2).

Only at a height of > 2.25 m above the emergency footpaths on the side, areas are marked in which easily deformable equipment elements, particularly traffic signs and warning signs, can be affixed, which may only extend up to 50 cm towards the traffic area. Jet fans necessary for ventilation must be arranged in recesses or ceiling coves. Light fixtures that can be deformed easily may extend up to 50 cm towards the traffic area in a height of > 3.75 m.

Table 1: Additional width for cross slope in tunnels with rectangular cross section

q [%] Additional width [cm]

> 3.5 to 4.5 5 > 4.5 to 5.5 10

>5.5 to 6.5 15

> 6.5 to 8.0 20

If jet fans are applied within the general construction dimensions, the emergency foot paths must be made wider as a

result depending on the diameter of the ventilators to be installed.

Often, it can be appropriate to apply road signs to the frontal walls of emergency bays.

In exceptions, road signs may come up to 30 cm close to the traffic area in a height of > 2.25 m above the emergency paths; this does not apply if a widening of the emergency paths is provided for fans. If road signs must be designed with lesser dimensions than specified in the administrative regulations [7], this must be consulted with the responsible traffic authorities.

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Light fitures may reach into the traffic area up to 30 cm on the side in exceptional cases if it is ensured that the unobstructed area between the top edge of the emergency path and the bottom edge of the light fixture at least comes to 4.10 m at every position. Jet fans with outside diameters ≤ 70 cm may be positioned in the upper corners in the safety area with a minimum distance on the sides of ≥ 30 cm to the traffic area as an exception.

Figures 3, 4 and 5 show positioning options for technical equipment elements in the standard cross section depending on the cross section shape resulting from the constructional requirements. Particularly for tunnels that are driven with water pressure with the help of digger-shield moles, restrictions regarding positioning and dimensions may be possible due to the cost-benefit ratio.

Figure 3: Equipment example rectangular cross section – depiction of the technical possibilities

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Figure 5: Equipment example circular cross section – tubbing – depiction of the technical possibilities

3. Lighting

3.1 General

Generally, tunnels must be provided with artificial lighting.

The requirements of the illumination of a tunnel are determined by the properties of the human eye. A person driving a vehicle at the maximum permitted speed must be able to clearly discern road and lane limitations, other vehicles as well as obstacles on the road at least as far as the stopping sight distance. The visibility of vehicles and obstacles depends on the lighting as well as on the reflection properties of the road surface and the tunnel walls.

The chosen level of lighting of a tunnel is the result of a consideration of the safety requirements (quality of lighting) and the costs (investments and operation). For the benefit of an economical design of the tunnel lighting without reducing the quality, the requirements of the tunnel lighting are determined according to the current status of technology, which deviate from the requirements in Sections 4.1.1.1, 4.1.2, 4.2 and 4.3 of DIN 67524 [8; 9].

Tunnels are classified into long and short tunnels according to DIN 67524 from a lighting-related point of view. According to this, the tunnel exit of a long tunnel from a lighting-related point of view cannot be

seen from the tunnel entrance from a stopping sight distance or the ratio of the tunnel length to the tunnel width is greater than 5:1. A short tunnel from a lighting-related point of view does not show these characteristics. The requirements of the lighting of long tunnels are described in Section 3.2; short tunnels (with respect to lighting) are illuminated according to DIN 67524.

Appendix A contains definitions of terms and calculation methods for determining the luminance in the approach area at daytime.

3.2 Lighting of long tunnels

The schematic layout of the luminance for driving through a long tunnel (with respect to lighting) corresponds to DIN 67524 (Appendix A, Figure 26). The requirements of the lighting level in the portal area of a tunnel are determined by:

- the speed limit

- the proportion of sky in the field of vision of the driver

- the portal design

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- the kind of lighting system

- the relation of wall luminance to road luminance - the stopping sight distance

- the traffic volume, type and composition - the traffic routing

The last five parameters and the maximum permitted speed also determine the lighting level in the interior zone.

Due to these numerous influences, no fixed values can be specified for the required luminance level of the threshold zone. The requirements must be determined by means of the methods described in the following.

For the requirements of the lighting system, a general differentiation is made between maintenance and planning values. The maintenance value of luminance LW is the value that must be at least met at

every point in time at which the lighting system is in operation.

The planning value of the luminance LPl is the result

of the product of maintenance value and planning factor:

LPl = fPl * LW (1)

The planning factor fPl depends on the life cycle of

the lamps, the planned cleaning intervals of the lighting system and the tunnel walls as well as the kind of control or regulation of the lighting system and must be selected according to economical aspects. In general, the planning factor is 1.5.

3.2.1 Lighting at daytime 3.2.1.1 Classes of lighting

With respect to the required lighting level, long tunnels are classified according to various parameters, which have an impact on the visibility task. These are traffic volume, traffic type and composition, the existence of slip roads and exits within the tunnel, the proportion of wall luminance and road luminance as well as visual guidance and driving comfort. Every one of the five parameters is assigned a weighting from the predefined values of table 2.

From the selected values, the sum of the weights is generated. This constitutes the class of lighting. If the parameters in the different zones of the tunnels vary, a different sum of the weights for the different zones results so that it may be necessary to plan the lighting of the threshold zone and the interior zone according to different classes of lighting.

3.2.1.2 Lighting of the threshold zone

The maintenance value of the road luminance of the threshold zone Lth is generated by means of the

following formula:

Lth = k * L20 (2)

The luminance in the approaching zone during daytime L20 (for determination see Appendix A) is

used as a calculation parameter for the visibility conditions in the approaching zone. In Table 3, the k values are specified under consideration of the stopping sight distance according to the “Regulations for building roads, Part: Line positioning” (RAS-L) [10]),

Table 2: Classification of long tunnels

Parameter Weighting

Traffic volume Vehicles per hour and lane 1)

One-way traffic Two-way traffic > 1200 > 650 – 1200 > 350 – 650 > 180 – 350 ≤ 180 > 1200 > 650 – 1200 > 350 – 650 > 180 – 350 > 100 – 180 ≤ 100 7 6 5 4 3 2

Slip roads and exits 2)_Exist

Do not exist

2 0 Type and composition of traffic Mixed traffic 3)

Vehicle traffic (HGV proportion > 15%) Vehicle traffic

2 1 0 Ratio wall lighting density LWd to road

lighting density LR4) LWd ≤ 0.4 LR 0.4 LR < LWd < 0.8 LR LWd ≥ 0.8 LR 4 2 0

Visual guidance and driving comfort 5) 2

1)_{Determined with the factor (1.5 * DTV)/(24 h * 2 * n) [n = number of lanes per direction]. The consideration of this factor contributes}

to the fact that approx. 75% of the traffic goes through during the daylight hours on average.

2)_{Also access roads to car parks or similar}

3)_{Mixture of slow, possibly non-motorised, and fast traffic road users} 4)_{Evaluated in the threshold zone; also applies for interior zone}

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Table 3: k values as function of the class of lighting, the stopping sight distance and the lighting system

k values for the threshold zone

Class of lighting Counter-beam lighting Symmetrical lighting

Stopping sight distance (m) Stopping sight distance (m) (Sum of weightings) 60 100 160 60 100 160 16 - 17 0.045 0.055 0.080 0.060 0.070 0.120 14 - 15 0.040 0.050 0.070 0.050 0.060 0.100 12 - 13 0.035 0.045 0.060 0.040 0.055 0.080 10 - 11 0.030 0.040 0.055 0.035 0.050 0.065 8 - 9 0.025 0.035 0.045 0.030 0.040 0.050 6 - 7 0.020 0.030 0.040 0.025 0.035 0.045 4 - 5 0.015 0.020 0.035 0.015 0.025 0.040

depending on the classification according to Table 2 for counter-beam lighting and symmetrical lighting. The k values for stopping sight distances other than those listed in Table 3 must be interpolated or extrapolated.

High L20 densities that only occur for a few hours per

year and would require a high threshold zone luminance, do not need to be considered if the speed limit in the approach zone and the tunnel is reduced accordingly during these times. In this way, the stopping sight distance is reduced and the luminance L20 decreases, because the proportion of the tunnel

opening in the 20° evaluation zone is greater and the proportion of sky for tunnels on level ground becomes smaller.

When driving through the threshold zone, the adaptation luminance decreases. This process can be disturbed by the physiological glare caused by the lights of the threshold zone. In addition, the physiological glare leads to reduced object contrasts and thus to a reduced visibility of obstacles and vehicles. Therefore, this glare must be as low as possible (see Section 3.2.4).

Due to the daylight reaching in to the tunnel, the first five metres of the threshold zone for tunnels with rectangular cross sections and the first 10 metres for tunnels with vault cross sections can remain without lighting. After half of the threshold zone, the luminance must be decreased continuously or in steps that should not exceed the ratio 1:3 to 40% of the original value until the end of the threshold zone.

3.2.1.3 Lighting of the transition zone

It is necessary to provide a transition zone after the threshold zone, within which the luminance must be reduced from the level at the end of the threshold zone to the luminance level of the internal tunnel zone. The road luminance (maintenance value) in the transition zone Ltr must be greater or equal the value

of the formula specified in the CIE publication 88 [11] Ltr ≥ Lth * (1.9 + t)-1.423 (3)

(with Lth = 100% and t in s). The luminance

distribution resulting from formula (3) can be approximated in steps that are smaller 3:1. The end of the transition zone is reached when the road luminance is smaller or equals the 3-fold value of the road luminance in the internal tunnel zone. Similar to driving through the threshold zone, it is also possible that disturbances due to glare occur, which must be considered and are dependent on the type of lighting and the lights used.

3.2.1.4 Lighting of the internal tunnel zone

The maintenance value of the road luminance in the internal tunnel zone Lin must be specified in

accordance with Table 4 depending on the stopping sight distance and the sum of the weightings according to Table 2.

In the proximity of emergency and breakdown bays, the luminance level of the emergency and breakdown bay and the road must be raised to the 3-fold value of the road luminance in the neighbouring interior tunnel zone.

Table 4: Minimum values of the average road luminance (maintenance value) for the internal tunnel zone

Luminances in the internal tunnel zone (cd/m2₎

Stopping sight distance (m) Class of lighting (sum of weightings) 60 100 160 16 – 17 4 7 12 14 – 15 3.5 6 10 12 – 13 3 5 8 10 – 11 2.5 4 6 8 – 9 2 3 5 6 – 7 1.5 2 4 4 – 5 1 1.5 -1) 1)_{not common}

In tunnels with one-way traffic, which are longer than 2500 m, the luminance of the interior zone can be lowered after 500 m to the level of the passage lighting at night;

however, it must not be lowered below 1 cd/m2

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The minimum values specified in Table 4 can be exceeded if the technical measures for realising the minimum values do not provide a balanced cost-benefit ratio.

3.2.1.5 Lighting of the exit zone

In the exit zone, it generally is not necessary to provide additional lighting to the internal tunnel lighting.

3.2.2 Lighting at night time

The road luminance of the entire tunnel zone must be 0.5 cd/m2 for one-way traffic and 0.8 cd/m2 for two-way traffic (maintenance value) at night for tunnels equipped with daytime lighting that lie on unlighted roads. Tunnels that lie on lighted roads must have the same luminance as the connecting roads that must be illuminated according to DIN 5044-1 [12]. The values of the night-time lighting can be raised if the technical measures for realising the minimum values do not provide a balanced cost-benefit ratio.

3.2.3 Uniformity of the luminance

In the threshold, transition and interior zone, the following requirements of the uniformity (for definition, see DIN 67524-1, Section 3) of the luminance must be observed:

- longitudinal uniformity Ul ≥ 0.6

- overall uniformity Uo ≥ 0.4.

3.2.4 Glare limits

The threshold value increase TI caused by the lighting system must not exceed 15% at daytime or night time in all tunnel zones. The following formulas are used to calculate TI in %:

2 , 8 . 0

650

i i Bl i F

E

TI

L

⋅

∑

θ

=

for LF

≤

5 cd/m2 (4)

950

₁_.₀₈ ₂, i i Bl i F

E

TI

L

⋅

∑

θ

=

for LF > 5 cd/m2 (5)

LF is the road luminance in cd/m2 of the

corresponding tunnel section according to Section 3.2.1. EBl,i is the luminance in lx at the eye of the

vehicle driver on level ground vertical to the direction of vision generated by the ith_light;

i

θ

is the angle in degrees between the line of vision and the connecting line between the eye of the vehicle driver and the light.

3.2.5 Flicker limits

The distance between the lights must be chosen in such a way that the frequency range of the brightness variation between 2.5 Hz and 13 Hz for passage through the tunnel at the drafted speed is ruled out for a period of more than 20 s, but not if this

would mean that the requirements of the luminance uniformity cannot be met. For this, see Figure 6.

Figure 6: Disturbance range due to flickering depending on the vehicle speed and the distance of the lights

3.3 Lighting system

3.3.1 Type of lighting

In general, counter-beam lighting (CBL) in contrast to symmetrical lighting (SL) leads to higher luminances on the road surface at the same luminous flux and to higher negative contrasts to the road surface of the threshold zone. Generally, counter-beam lighting must be provided to illuminate the threshold and transition zones for economical reasons. It is necessary to provide reasons for the use of symmetrical lighting. For economical reasons, road surfaces with different reflection factors κρ (for a

definition, see DIN 5044-2, Section 3.3) must be selected for counter-beam and symmetrical lighting systems. For more details, see Section 3.4.

Irrespectively of the type of lighting used for the threshold zone, the lights of the passage lighting can also be operated in all switching levels of the threshold zone lighting.

3.3.2 Lamps

For economical reasons, high-pressure sodium vapour lamps should generally be used. It is also possible to use low-pressure sodium vapour lamps as spot lights in the interior zone. Due to the inferior colour reproduction of these lamps, traffic and information signs, however, should be illuminated. Other lamps can be used if this is as at least as economical as using sodium vapour lamps.

3.3.3 Light fixtures

Light fixtures are mainly used to direct the generated light beams in such a way that the highest possible

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luminance and a uniform luminance distribution is achieved on the road surface.

Requirements of the light fixtures, such as resistance to corrosion of the lights including their mounting parts, the degree and class of protection are determined in the “Additional technical terms and regulations for civil engineering works ZTV-ING, Part 5: Tunnel construction, Section 4: Operational equipment of road tunnels”.

3.3.4 Light arrangement

The light arrangement is determined by the tunnel cross section as well as by light- and maintenance-related criteria. The criteria that must be considered when deciding on the light arrangement can be found in Table 5. For economical reasons, a single-row light arrangement should be chosen if possible. For arrangement of the lights in corners, too, it is generally necessary to provide counter-beam lighting for the threshold and transition zone lighting.

3.3.5 Control or adjustment of the lighting system

The strongly varying light conditions during daytime lead to requirements of the luminance level in the

different tunnel sections, which change according to the time of day. The control or adjustment system is used to adapt the luminance in the different tunnel sections to the daytime light conditions continuously or in steps as small as possible, i.e. in at least 6 steps, and to the requirements depending on the time of day (day/night).

The hourly traffic volume, which generally changes in the course of the day, can lead to different current classifications according to Section 3.2.1.1 at different times of the day and thus to altered current requirements of the lighting. If the hourly traffic volume is acquired per direction of traffic, the thus resulting current classification can be considered as a parameter in the control or adjustment system. For a respective variation curve of traffic (with a lower traffic volume around midday), it can be possible to select a lower lighting level for the hours around midday in case of a high outside brightness than would be necessary according to the specifications in Section 3.2.1.1.

RABT - 2006_eng

ROAD AND TRANSPORTATION RESEARCH ASSOCIATION

Regulations

for the

equipment and operation

of road tunnels

RABT

Edition 2006

Reproduced with permission of the Road and Transportation Research Association

publishing company (FGSV-Verlag). Authoritative for the application of the Road and

Transportation Research Association regulations shall be the version with the latest date

of issue, which is available at the Road and Transportation Research Association

publishing company: FGSV-Verlag, Wesselinger Staße 17, 50999 Köln (Germany).

BMVBS ARS no. 10/2006

Appendix 2

Specification of the administrative authorities

ROAD AND TRANSPORTATION RESEARCH ASSOCIATION

Regulations

for the

equipment and operation

of road tunnels

RABT

Edition 2006

Reproduced with permission of the Road and Transportation Research Association

publishing company (FGSV-Verlag). Authoritative for the application of the Road and

Transportation Research Association regulations shall be the version with the latest date

of issue, which is available at the Road and Transportation Research Association

publishing company: FGSV-Verlag, Wesselinger Staße 17, 50999 Köln (Germany).

WORKING GROUP TRAFFIC ROUTING AND ROAD SAFETY

Table of contents

0. Introduction

0.1 Content

0.2 Purpose

0.3 Validity

0.4 Overall safety concept

0.5 Risk analysis

1. Organisation and operation

1.1 Organisation

1.2 Monitoring, control and maintenance

2. Traffic area tunnel

2.1. General

2.2 Longitudinal tunnel inclination

2.3 Tunnel cross section, unobstructed

area, traffic area

3. Lighting

3.1 General

3.2 Lighting of long tunnels

650

650

E

TI

L

⋅

∑

θ

=

≤

950

E

TI

L

⋅

∑

θ

=

θ

3.3 Lighting system