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Law + Order Maintenance of Performance of Electric Security System in Tunnelling

Fire Prevention in Tunneling

Safety Objectives and General Provisions

EC Tunnel Directive 2004/54/EG (Edition 2004)
Directive 2004/54/EC of the European Parliament and of the Council of the European Union on minimum safety requirements for tunnels in the Trans-European Road Network

Publisher: The European Parliament and the Council of the European Union

»Article 1: Subject matter and scope
(1) This Directive aims at ensuring a minimum level of safety for road users in tunnels in the Trans-European Road Network by the prevention of critical events that may endanger human life, the environment and tunnel installations, as well as by the provision of protection in case of accidents.
(2) It shall apply to all tunnels in the Trans-European Road Network with lengths of over 500 m, whether they are in operation, under construction or at the design stage.«

ZTV-ING (Additional Technical Conditions of Contract for Civil Engineering Structures) Part 5 Para 4 (Edition 2009)
Additional Technical Conditions of Contract for Civil Engineering Structures, Part 5 Tunnelling, Section 4 Technical Equipment used in the Operation of Road Tunnels

Publisher: Forschungsgesellschaft für Straßen- und Verkehrsführung (FGSV – Research Foundation for Road and Traffic Routing)

»(1)... (ZTV-ING T5 A4) applies to the new construction, maintenance and modernization of technical equipment used in the operation of road tunnels ... «

ZTV-ING T5 A4 describes the configuration (design loads, ensuring a long service life, other requirements to construction and system parts, requirements on fasteners and suspension devices), ancillary civil works (surveying, waste management), suitability and function tests (at the manufacturer, on site) and the as-is documents required for the technical equipment used in the operation of road tunnels.

TL/TP TTT (Edition 2010)

Technical delivery terms and technical testing standards for doors and gates in road tunnels
Publisher: Federal Highway Research Institute (Bundesanstalt für Straßenwesen - BASt)

» 1 (1) The “Technical delivery terms and technical testing standards for doors and gates in road tunnels (Technische Lieferbedingungen und Technische Prüfvorschriften für Türen und Tore in Straßentunneln - TL/TP TTT) contain the relevant requirements for the manufacture and installation of gates and doors for emergency exits (in escape and rescue routes and emergency rooms) in road tunnels.«

RABT (Edition 2006; Germany)
Directives on the Configuration and Operation of Road Tunnels
Publisher: Forschungsgesellschaft für Straßen- und Verkehrsführung (FGSV)

General Road Construction Newsletter (ARS) No. 10/2006
Re: Technical Equipment used in the Operation of Road Tunnels

Implementation in national law of Directive 2004/54/EC on minimum safety requirements for tunnels in the Trans-European road network

Directives on the Configuration and Operation of Road Tunnels – (RABT), Edition 2006

Publisher: Federal Ministry for Traffic, Construction and City Development (BMVBS)

»In recent years, possible measures to increase the safety of users have been extensively tested against the background of severe fire accidents in some tunnels in the Alps. In this context, the EU Commission (KOM) issued the Directive 2004/54/EC … (EC Tunnel Directive). As part of the necessary national implementation ... the (RABT regulations) ... have been updated and now exist as Edition 2006 ... An important aspect in the new regulations is, inter alia, the improvement of self-rescue possibilities for users in the event of an accident. In this respect it is of particular importance that such safety facilities are designed and implemented as uniformly as possible in all road tunnels.

0.1 Contents
The ... (RABT regulations) contain principles, notes and requirements for the planning and operation of road tunnel facilities.

0.2 Scope
The RABT regulations apply to all tunnels intended for road traffic with an uninterrupted length of 80 m. These regulations additionally apply to existing tunnels from a length of 400 m and, under the restriction of commensurability, also for tunnels between 80 m and 400 m length.

0.4 Overall safety concept
These regulations are not a fixed benchmark. Rather, their application requires that a balanced approach be taken and the many and varying requirements resulting from traffic quality, safety and economy as well as environmental conditions be considered and incorporated into an overall safety concept. At the outset, a typical damage scenario must be determined (accident, fire, truck, car, etc.). This concept must then provide solutions for loss prevention, damage reports, self-rescue and third-party rescue of lives as well as assistance after accidents and fire fighting by emergency rescue services.

Constructional measures necessitated by this overall safety analysis must then become a part of the planning approval documents. «

MLAR (Edition 2005)
Model Directive on Fire Protection Requirements for Wiring Systems (Model Wiring System Directive)

Publisher: Expert commission on construction supervision of the Ministerial Conference of the Minister of Construction and Housing

MLAR regulations apply in connection with the Model Building Regulations (MBO) and DIN 4102 /EN 13501-2 (Fire Resistance of Building Material and Construction Products) for any type of building. It specifies the minimum requirements in terms of fire protection for wiring systems.

An important aspect of the MLAR regulations are the fire-protection related minimum requirements on the maintenance of performance for electric wiring systems – cables and distributors of safety-related systems – in the event of a fire. It is advisable to include these in the overall safety concepts of road tunnels.

Maintenance of Performance in Tunneling

EC Tunnel Directive 2004/54/EG (Edition 2004)

»Foreword: Maintaining a high safety level requires proper maintenance of the safety facilities in tunnels.
Safety measures as referred to in Article 3
2.17.1. All tunnels shall have an emergency power supply capable of ensuring the operation of safety equipment indispensable for evacuation until all users have evacuated the tunnel
2.17.2. Electrical, measurement and control circuits shall be designed in such a way that a local failure, such as one due to a fire, does not affect unimpaired circuits.
2.18. Fire resistance of equipment ... The level of fire resistance of all tunnel equipment shall take into account the technological possibilities and aim at maintaining the necessary safety functions in the event of a fire.
Cf. “Table displaying informative summary of minimum requirements”, ibid..«

ZTV-ING Teil 5 Abs. 4 (Edition 2009)

»2.2 Design loads
(Reference to Section 1 No. 3.2.4

3.2.4.2 Pressure and suction on sheathing
Tunnels with a clear cross-section of 50 m² or more, sheathing must be dimensioned for pressure and suction of 0.5 kN/m². Suction increases in tunnels with a smaller cross-section. For a clear cross-section of 43 m² and less a suction of 0.8 kN/m² results. Intermediate values result from linear interpolation. 

2.4. Other requirements on construction and system parts
2.4.2 Maintenance of performance under thermal stress
For a minimum period, certain mandatory safety facilities must maintain their fully designed performance under thermal stress.«

RABT (Edition 2006; Germany)

»7. Central facilities

7.1 Technical rooms
Fire compartments must be determined if it is required to maintain the performance of individual groups of equipment. Connecting doors for fire compartments must fulfil a fire resistance period of 90 minutes.

The equipment listed below must be installed in separate rooms and their functional reliability must be ensured in the event of a fire:

a) medium voltage switchgear and transformers
b) low voltage switchgear
c) waiting room with central control and communication system (ZLT), fire alarm system, loudspeaker system, video system, radio system, measurement and control systems
d) UPS – supply systems with batteries
e) road telecommunication systems (for motorways).

7.3 Power supply

7.3.3 Electrical installations
Low voltage systems
Depending on local conditions (length of cable section, amount of load capacity), electrical power consuming devices must be connected

  • directly to the main switchgear or
  • via additional sub-distribution boards.

Independent of the required maintenance of performance for certain system parts, the security of energy supply must principally be designed so that no section of more than 300 m can fail in case of an incident. In general, sub-distribution boards are to be install in emergency call stations.

Emergency power supply systems
In case of a power failure, the power supply of certain power consuming devices is provided via static DC/AC converter and battery systems (static UPS system). The dimensioning of the UPS-system must consider the power consumption of the following facilities:

  • escape route signage
  • orientation lighting
  • emergency lighting
  • evacuation route lighting
  • lighting, technical rooms,
  • traffic-related technical facilities
  • communication systems
  • fire alarm systems
  • control equipment
  • measuring equipment

7.3 .4 Cables and wires
The section cabling of the tunnel cross-section must be configured according to E90 standards (maintenance of insulation 180 minutes, maintenance of performance 90 minutes) for the UPS-supplied part of the night/emergency lighting as well as for the ventilation connections and extinguishing installations. The repair safety switch must be installed in the nearest emergency call booth and/or in the electricity distributor. «

MLAR (Edition 2005)

»5 Maintenance of performance of electrical wiring systems in the event of a fire

5.1 Essential requirements
5.1.1 Electrical wiring systems for safety-related equipment and facilities required by building code regulations must be designed or otherwise separated by construction products so that the safety-related equipment and facilities remain functional for a sufficient amount of time in the event of a fire (maintenance of performance). This maintenance of performance must be guaranteed also in the event of a possible interaction with other equipment, facilities or their parts.

5.1.2 Other safety-related equipment and facilities required by law and necessary for operation may be connected to the distributors of electrical wiring systems for safety-related equipment and facilities required by building code regulations. It must be guaranteed that the operation of safety-related equipment and facilities required by building code regulations are not being impaired.

5.2 Maintenance of performance
5.2.1 The maintenance of performance is assured if the wiring meets the test requirements of

DIN 4102-12:1998-11 (maintenance of performance class E30 to E90) of if they are laid on bare floors below the floor topping with a minimum thickness of 30 mm or if they are laid into the ground.

5.2.2Distributors for electrical wiring systems with a maintenance of performance function … must be installed in rooms not otherwise used for other purposes. These rooms must be separated from other rooms by walls, ceilings and doors made of non-combustible material (with the exception of doors) and a fire resistance corresponding to the duration of the maintenance of performance function. They must be separated by cabinets that are certified by usability certification under building legislation to maintain the function of electrotechnical installations in the event of a fire for the necessary duration of the maintenance of performance function. Alternatively, they are enclosed by construction products (including their closures) with a fire resistance corresponding to the necessary duration of the maintenance of performance function and are made of non-combustible building material (with the exception of enclosures). It must be guaranteed that the function of the electrotechnical installations of the distributor is assured in the event of a fire for the duration of the maintenance of performance function. «