F2A équipementier en traitement de l'air
en fr
Home > Our markets > Tunnel

Tunnel

  • Over 20 years experience
  • Many references
  • Road and Railroad tunnel
  • Smoke exhaust solutions

 

Download file

Traffic can reach up to 200 000 vehicles a day in a road tunnel and the safety of users is a major issue. A fire taking place in a tunnel can have awful consequences and the smoke propagation speed can sometimes reach 4m/second.

 

Context and issue

The risks of a fire in a confined space are: Asphyxia, loss of visibility, explosion, collapse and the rise in temperature.

Rise in temperature and radiation

In case of a light or heavy vehicle catching on fire, the heat emitted is extremely dangerous for men and safety distances must be observed to ensure the user’s survival.

Propagation of smoke

Smokes swiftly spear throughout the tunnel causing a loss of visibility and asphyxia.

Smoke exhaust processes

Depending on the tunnel’s typology different solutions are set up.

Longitudinal ventilation

It is designed to push the somkes towards the entrance of the tunnel by the mean of axial fans. There also exists variants of that strategy, using massive extraction dampers.

Transversal ventilation

In the event of fire, it is designed to renew the tunnel’s air by extracting the smoke through the ceiling and blowing fresh air through the bottom.

Equipments requirements

The many elements composing the ventilation system are subject to security standards testing their heat resistance.

Acoustic constraints

 

Context and problematic

Acoustic in tunnels must be taken care of in regards to both users and neighbors.

Road and railway tunnels

Road and railway tunnels are not always subject to acoustic measures. Silencers and acoustic walls can be applied in some situations.

Subway tunnel

Subway tunnels are located in urban areas and receive public. Acoustic measures inside are set  by the Engineering office and the neighbor’s noise regulation.

Material characteristics

Extensive studies must be led in order to set up the optimum solution so as to reach the acoustic objective.

 

Download file

Safety in road tunnels:

2000-63 Directive

It describes the measures to be taken for sanitary ventilation and smoke exhaust in a tunnel. It recommends a heat resistance test for the smoke dampers, following an accurate protocol:

Time Position T°in the tunnel T° in the duct
15 min Opening 400°C 20°C
60 min Opening and closing 200°C 200°C
60 min Opening 400°C 200°C

 

The splitters and silencers are not specifically called in the directive, but since they are located close to the fans in transversal and semi transversal ventilation, it can be considered that they have to be 200°C for 2hours resistant, or 400°C for 2hours resistant if they are located close to the smoke exhaust dampers.

http://www.vie-publique.fr/documents-vp/circulaire_25-08-2000-1.pdf

The CETU (Center of Tunnel Studies)

In 2003 they edited a ventilation file explaining the different strategies of transversal or longitudinal smoke exhaust processes. It also gives many specifications regarding the sizing of dampers or the calculation of the optimal air flow depending on the situation (sanitary or smoke exhaust ventilation)

 http://www.cetu.developpement-durable.gouv.fr/IMG/pdf/DP_ventilation_cle557d66-3.pdf

 

Safety in train tunnels

Technical ministerial instruction n°98-300

It describes the measures to be taken for safety in road rails tunnels. A smoke exhaust strategy is mandatory in tunnels located in an urban area and dedicated to public transport as well as in tunnels over 5 000 m long where the transport of hazardous materials is allowed.

 http://www.developpement-durable.gouv.fr/spip.php?page=article&id_article=3249

 

European and international regulations:

 

European Directive 2004/54/CE

It describes the measures to be taken regarding the cooperation between the different security centers of  a trans-European tunnel. It also explains the necessity of installing massive extraction dampers in bidirectional trans-European tunnels over 3 000 m long.

 http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2004:167:0039:0091:FR:PDF

 

World Road association

The WRA is an organization that publishes and gathers different elements regarding fire safety in tunnel throughout the world, be it on heat regulation, pressure regulation or leakage rates. Its activity is close to the CETU’s and their files also contain data on sizing and calculation.

http://tunnels.piarc.org/fr/equipements-et-systemes/ventilation.htm

BS476-20

The 20th article of the British Standard applies to fire and smoke dampers. The protocol is composed of:

An integrity test  with a closed damper following the ISO 834 curve (curve T°/time)
An fire tightness test :  -     No flames shall go through the damper during the test

A rod of more than 6 mm in translation of more than 250 mm through the damper shall not go through it
A 21 mm rod shall not go through the center of the damper 

 

UL555S

The UL555S (Underwritters Laboratories) specifically describes the necessary test on a smoke damper so that it can be used in the USA or in any other country that uses this regulation. Its requirements cover smoke dampers used in Heating, Ventilation and Air-Conditioning (HVAC). The tests are always operated on 3 dampers (max height/max width, min height/max width, max height/min width).

The tests on the smoke dampers bears on different criteria:

Operability: 100 000 operating cycles from opened to closed via all the intermediate positions of the blades.
Heat resistance : beginning at a temperature of 121C° with a rise of 56°C every 30minutes in closed position
The leakage rate is measured by applying heavy water pressure (from 1.1kPa to 3.1Pa) on the damper. It is then evaluated from class 1 to 3 depending on the results.

 

Acoustic regulation:

Neighboring noise, 2006-1099 directive, August, 31 2006

It describes the regulations that tunnel’s equipments are subject to when they are near an inhabited area. The maximum values for emerging sounds are 5dBA by day and 3dBA by night.

http://www.legifrance.gouv.fr/affichTexte.do?cidTexte=JORFTEXT000000459023&dateTexte=&categorieLien=id

 

<p><strong>Acoustic splitter 400°C/2h</strong></p>

Acoustic splitter 400°C/2h

SONIE BD

Tunnel


Read more
<p><strong>400°C/2h damper </strong></p>

400°C/2h damper

MO-D / MS-D

Tunnel


Read more
<p><strong>BS 476 fire damper</strong></p>

BS 476 fire damper

TRS

Tunnel


Read more
<p><strong>Custom-made flexible sleeve</strong></p>

Custom-made flexible sleeve

ELYFORM

Tunnel - Tertiaire


Read more
Croix Rousse Tunnel

Croix Rousse Tunnel

Lyon

Due to its urban location and the heavy traffic, this 1 757 meter long tunnel has specific requirements. The dense traffic (47 000 vehicles per day) puts the ventilation elements...

Read more
Cairo

Cairo's subway

Cairo

Cairo is the most densely populated city in Africa and in the Arabian world and its transport needs are considerable. It was estimated that its public transport system can handle up to 4.9...

Read more
Neuilly

Neuilly's tunnel

Neuilly, Paris

In 2009 Paris City Hall launched a series of renovation on its 22 urban tunnels. Among them, the Neuilly tunnel, 440 m long, in the center of Paris.

To...

Read more
Maurice Lemaire Tunnel

Maurice Lemaire Tunnel

Vosges Moutain

The Maurice Lemaire tunnel is one of the longest tunnels in France (6 950 m). It is located between Saint-Marie-aux-Mines(68) and Lusse (88) and has been subject to a vast program of...

Read more