Traditional Chinese Simplified Chinese Email this article
LCQ14: Number 3 alarm fire inside Lion Rock Tunnel

     Following is a question by the Hon Ip Wai-ming and a written reply by the Secretary for Transport and Housing, Ms Eva Cheng, in the Legislative Council today (March 21):


     A Number 3 alarm fire which was caused by repair works on underground water mains broke out inside the Lion Rock Tunnel (the Tunnel) on March 8 this year.  The incident has not just necessitated a two-week closure of the Tunnel for emergency repairs, but has also aroused public concern about issues of safety and means of escape in respect of the tunnels built in early days.  In this connection, will the Government inform this Council:

(a) whether the authorities have drawn up and updated the measures and equipment for safety management, emergency contingency plans for incidents inside tunnel tubes, and conducted regular training and drills for the road tunnels and cross-harbour tunnels built in different periods in Hong Kong; if they have, of the details; if not, the reasons for that;

(b) whether the drencher system installed inside the tubes of the Tunnel was activated when the aforesaid fire broke out; if not, of the reasons for that; whether the drenchers functioned normally whenever a fire broke out or a drill was conducted inside the tubes of the Tunnel in the past three years; if not, of the number of failures and the details;

(c) whether it knows, apart from the Tunnel, if the design of at-grade vehicular traffic with underground piping for public utilities is currently adopted for any road tunnel, cross-harbour tunnel or rail tunnel in Hong Kong; if so, the details of the tunnels concerned and the public utilities for which piping has been laid; how the authorities ensure the industrial safety of the workers who carry out repairs and maintenance for the tunnels and such underground facilities (including whether they will brief the workers on the escape facilities before commencement of the works); and
(d) whether it knows, in addition to the Tunnel, which tunnels in Hong Kong are not equipped with escape doors or tubes, and rely only on tunnel exits as emergency exits; whether the authorities have considered adding a pedestrian escape tube inside the Tunnel and such tunnels in order to ensure the safety of tunnel users and other people concerned; if they have, of the details; if not, the reasons for that?



     At about 3.30am on March 8, 2012, a fire broke out when a works contractor of the Water Services Department was carrying out water mains replacement and rehabilitation (R&R) works inside an underground utility chamber underneath the south-bound tube of the Lion Rock Tunnel (LRT).  All workers carrying out the R&R works immediately followed the site emergency procedures and evacuated safely.  No one was injured.  The fire was put out at around noon that day and the Fire Services Department (FSD) is investigating the cause of the incident.

     As a result of the fire, the south-bound tube of LRT was once completely closed.  The Transport Department (TD) activated the contingency measures immediately and implemented emergency traffic arrangements with relevant departments, the LRT operator and public transport operators to maintain smooth traffic between Sha Tin and Kowloon as far as possible.  The fast lane of the south-bound tube of LRT was re-opened to traffic at 6am on March 12, 2012 after round-the-clock emergency repair works by the Highways Department (HyD), and the slow lane also resumed normal operation at 6am on March 19 after days of 24-hour expedited repair works by HyD.  During the period when the repair works were carried out, the traffic at LRT was slightly more congested than usual but generally remained normal.

     My reply to the various parts of the question is as follows:

(a) All road tunnels and cross-harbour tunnels in Hong Kong are equipped with facilities that meet safety standards, including fire service installations and equipment (FSI) required by FSD such as fire hydrant/hose reel systems, portable fire extinguishers, smoke extraction systems and emergency lighting systems.  The FSI requirements are formulated by FSD according to relevant legislation as well as the conditions of individual road tunnels and actual operational needs.  Every tunnel operator is required under the law to engage a registered fire service installation contractor to conduct annual inspection on FSI to ensure their compliance with relevant standards and legal requirements.

     In addition, FSD, TD and all tunnel operators have drawn up contingency plans for handling emergency incidents including fires.  In handling a tunnel incident, TD is responsible for co-ordinating emergency traffic and public transport arrangements and disseminating relevant information on a real time basis.  On average, individual tunnel operators will conduct fire drills every six months jointly with relevant departments, including TD, FSD and the Police to test the effectiveness of the contingency plans and functionality of FSI.  Such drills ensure the efficient and prompt execution of the contingency plans in case of tunnel emergencies.  Relevant Government departments will also review from time to time the contingency measures with the tunnel operators and make adjustments when necessary.

(b) The south-bound and north-bound tubes of LRT are each installed with 11 drenchers, which are used primarily for isolating the fire and preventing it from spreading inside the tunnel tubes.  The fire that occurred inside LRT on March 8, 2012 originated from an underground utility chamber below the tunnel tube rather than from the tunnel tube itself.  As advised by the on-scene FSD officers, the LRT operator did not actuate the drenchers as the water sprayed from the drenchers could not check the spread of the underground fire.

     In the past three years, only one fire incident occurred inside the tunnel tubes of LRT, during which the drenchers were actuated to prevent the spread of the fire.  At every fire drill conducted in these three years, the tunnel operator actuated and tested the drenchers and all of them functioned normally during the tests.

(c) Each of the two tunnel tubes of LRT is equipped with utility chambers underneath.  Two water mains each with a diameter of 1.2 metres (m) and one with a diameter of 1.4m are laid inside the utility chambers below the Kowloon-bound (i.e. south-bound) tube, whereas two water mains each with a diameter of 1.5m are laid inside the utility chambers below the Sha Tin-bound (i.e. north-bound) tube.  Apart from LRT, only the Tseung Kwan O Tunnel (TKOT) and the Cross-Harbour Tunnel (CHT) have utility chambers running underneath the tunnel tubes.  There are one water mains and one towngas pipe running underneath the tunnel tube of TKOT.  The utility chamber housing the towngas pipe is a standalone one completely separated from the tunnel tube above with a monitoring system installed to ensure safety.  As for CHT, telecommunications and power cables are laid inside the utility chambers underneath the tunnel tubes.

     As stipulated in the occupational safety and health legislation, employers, including contractors engaging in repair and maintenance (R&M) works of road tunnels and their underground facilities, have to adopt adequate measures to ensure work safety and health of their workers.  Such measures include providing a safe system of work and devising emergency plans.
     To ensure that the workers of the works department / utility companies and contractors engaging in tunnel R&M works are fully aware of the means of escape and safety facilities inside the tunnels and their underground utility chambers before making an entry, the tunnel operators will explain to the safety officers of the contractors on the safety matters that workers should be aware of when carrying out works inside the tunnel tubes, including the means of escape and other safety facilities.  Before each entry into the tunnel tubes, R&M workers have to provide their contact numbers to the tunnel operator for communication between tunnel staff and the workers in case of emergency.  Furthermore, to ensure safety of the workers and tunnel users, all R&M works inside the tunnel tubes (and the underground utility chambers) will be conducted only when the tunnels are completely closed (except the towngas pipe utility chamber underneath TKOT as workers can enter the utility chamber directly to carry out R&M works via an access outside the tunnel tube without affecting the operation of the tunnel).

     Apart from the above measures, R&M works inside the utility chambers underneath the tunnel tubes are classified as works in confined spaces, which shall be governed stringently by the Factories and Industrial Undertakings (Confined Spaces) Regulation.  The Regulation requires, among other things, that a risk assessment should be carried out by a competent person to ensure safety at the works site before entry into a confined space.  Contractors of the works department / utility companies are required to take all necessary safety precautions in accordance with the recommendations of the risk assessment report, such as providing in a satisfactory condition a sufficient supply of equipment for rescue and safety protection, and emergency escape, before issuing certificates to the workers for allowing their entry into the underground chambers to carry out the R&M works.  All workers entering the confined spaces must be certified workers holding valid certificates.  Also, workers conducting the R&M works at underground utility chambers have to follow the safety guidelines compiled by the TD and tunnel operators as well as relevant safety legislation to ensure their safety at work.

(d) Except LRT, all other tunnels in Hong Kong are equipped with emergency escape accesses (EEAs) between the two tunnel tubes.  In case of emergency, tunnel users may travel from the tube where the incident takes place to the other tube via EEAs and leave the tunnel.  The two tubes of LRT were constructed at different times.  EEAs connecting the two tubes were not built as the first tube had already been open to traffic when the second one was constructed.

     As mentioned in the reply to part (a) above, LRT is now equipped with FSI that comply with relevant legislation and FSD's requirements, and FSD, TD and tunnel operators have drawn up contingency plans and will conduct emergency and fire drills regularly.  Therefore, the existing FSI and safety measures of LRT are able to effectively facilitate the safe and timely escape of tunnel users and workers in case of emergency.  In fact, the contingency plans functioned effectively during the fire incident that occurred inside LRT on March 8, 2012.  All workers carrying out water mains rehabilitation works inside the underground utility chambers followed the emergency procedures and evacuated safely.  No one was injured.

     If EEAs were to be built to connect the two existing tunnel tubes of LRT, one of the tubes will have to be closed to make room for the works site.  Prolonged tube closure will be necessary during the works, which will seriously affect the traffic between Kowloon and the New Territories East.

Ends/Wednesday, March 21, 2012
Issued at HKT 11:59


Print this page