ISO 37175:2024

International
Standard
ISO 37175
First edition
Smart community infrastructures —
2024-08
Operation and maintenance of
utility tunnels
Infrastructures urbaines intelligentes — Exploitation et
maintenance des tunnels techniques
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Benefits to stakeholders . 3
4.1 General .3
4.2 Authorities.4
4.3 Investors.4
4.4 Developers .4
4.5 Operation providers .4
4.6 Maintenance providers .5
4.7 Pipeline operators .5
4.8 Citizens .5
5 Basic elements and overall requirements . 5
5.1 General .5
5.2 Utility tunnel body .6
5.3 Ancillary facilities .6
5.4 Pipelines .6
5.5 Operation and maintenance management platform (OMMP) .7
6 Operations and maintenance . 8
6.1 General .8
6.2 Operations .8
6.2.1 General .8
6.2.2 Duty .8
6.2.3 Detection and monitoring .9
6.2.4 Routine inspection .9
6.2.5 Safety operations .10
6.2.6 Financial management .11
6.3 Maintenance . 12
6.3.1 General . 12
6.3.2 Requirements . 12
6.4 Management . . . 12
6.4.1 Emergency management . 12
6.4.2 Data management . 13
6.4.3 Space management . 13
6.4.4 Energy savings and emissions reduction .14
7 Evaluation and continuous improvement . 14
7.1 General .14
7.2 Sustainability evaluation . 15
7.2.1 Evaluation principles . 15
7.2.2 Evaluation elements . 15
7.3 Continuous improvement . . 15
7.3.1 General . 15
7.3.2 Technology improvement .16
7.3.3 Management improvement .16
7.3.4 Improvement methods .16
Annex A (informative) Evaluation elements . 17
Annex B (informative) Application of BIM, GIS and CIM in OMMP .20
Bibliography .21

iii
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
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This document was prepared by Technical Committee ISO/TC 268, Sustainable cities and communities,
Subcommittee SC 1, Smart community infrastructures.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
Introduction
A utility tunnel is typically constructed underground to carry pipelines. A utility tunnel is also used to carry
communications cables such as telecommunication cables, radio cables and television cables.
In a smart community, a utility tunnel is an important part of the infrastructure that accesses energy
distribution, city information / data acquisition as well as transmission systems, while also being crucial for
the redistribution of social resources. It is a valuable aspect of public infrastructure and a lifeline to ease the
congestion of community traffic by fully utilizing the community underground space.
If the utility tunnel is well-planned, constructed and managed, it can have the following advantages:
— effectively conserves underground space;
— reduces the need for repetitive road / pavement excavations in contrast to traditional buried pipelines;
— eliminates the risk of overhead facility accidents caused by inclement weather, thereby enhancing the
landscape and public safety of the community;
— reduces the operation and maintenance costs of pipelines and improves infrastructure management;
— increases community energy carrying capacity and promotes community efficiency and sustainable
development.
This document provides a general overview and framework for the operation and maintenance of utility
tunnels. It aims to provide requirements and recommendations for stakeholders of utility tunnels to improve
safety, maintainability, cost-effectiveness, technology application, sustainability and management efficiency.
This document benefits the stakeholders of utility tunnels, including but not limited to, authorities,
investors, developers, operation providers, maintenance providers, pipeline operators and citizens. It
provides requirements and recommendations for cooperation between the public and private sectors and
their regulators. Effective cooperation ensures the safe, orderly and intensive development and rational
utilization of community underground space. The document also assists operation and maintenance
providers in delivering safe and reliable energy supply services, improving the quality of community living
for citizens.
This document contributes to the digitalization and smartness of the operation and maintenance of utility
tunnels. Several global innovations have been made for the digitalization and smartness of the operation
and maintenance of the utility tunnel, such as:
1)
— National Underground Asset Register (NUAR) in the UK provides a digital map for stakeholders to
access information about underground pipelines and cables, enabling stakeholders to obtain the data
required for safe operation and maintenance based on their roles;
— The community underground pipeline network management platform in China are integrated platforms,
2)
for example, Beijing Government Services ;
3)
— Before You Dig Australia (BYDA) in Australia is a national infrastructure information system platform
that ensures the safety of construction workers and communities during excavation projects, promoting
the vision of zero damage and zero harm.
This document encourages a platform-based approach for managing the operation and maintenance of the
utility tunnels. It aims to strengthen information exchange and sharing, and ensure the safe and effective
operation and maintenance of the utility tunnels.
1) https://www.gov.uk/guidance/national-underground-asset-register-nuar
2) https://banshi.beijing.gov.cn/
3) https://www.byda.com.au/
v
International Standard ISO 37175:2024(en)
Smart community infrastructures — Operation and
maintenance of utility tunnels
1 Scope
This document specifies requirements and recommendations for the operation and maintenance of utility
tunnels in terms of application, safety, energy conservation, advanced technology and economic rationality.
This document aims to ensure the sustainable development as well as safe and stable operation and
maintenance of utility tunnels.
This document is applicable to communities of any size that have utility tunnels.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
utility tunnel
enclosed structure and ancillary facility built under the city to access two or more pipelines, e.g. electricity
cables and water supply pipes
Note 1 to entry: A utility tunnel is also used to carry communications cables such as telecommunication cables, radio
cables and television cables.
Note 2 to entry: For the purposes of this document, "utility tunnel" is used, but other terms that can be used such as
utility corridor, common services tunnel, common ditch or utilidor.
3.2
utility tunnel body
enclosed structure that can independently withstand the effects of external water and soil within the design
service life, including the main body structure of the utility tunnel and the various entrances and exits,
maintenance roadways, ventilation ducts and other structures
3.3
ancillary facility
supporting facility of the utility tunnel for the purpose of safe operation and maintenance
EXAMPLE Firefighting system, ventilation system, power supply system, illumination system, monitoring and
alarm system, water supply system, drainage system and identification system.
3.4
pipeline
pipe or cable utility line that is installed inside the utility tunnel for carrying water, rainwater, sewage,
reclaimed water, gas, heating water, cooling water, steam, electricity and communication data

3.5
operation and maintenance management platform
OMMP
integrated platform that meets the monitoring, management, processing, and decision-making needs of
stakeholders of a utility tunnel based on the latest smart community infrastructure technologies, e.g. smart
monitoring, Internet of Things (IoT), big data, building information modelling (BIM), geographic information
system (GIS) and related smart equipment
Note 1 to entry: An OMMP should be reliable, safe, advanced, usable, maintainable, extensible and open.
Note 2 to entry: An OMMP should be able to be accessed to the development map of the utility operator and provider.
3.5.1
building information modelling
BIM
use of a shared digital representation of an asset to facilitate design, construction and operation processes
to form a reliable basis for decisions
[SOURCE: ISO 23386:2020, 3.6]
3.5.2
geographic information system
GIS
information system dealing with information concerning phenomena associated with location relative to
the Earth
[SOURCE: ISO 19101-1:2014, 4.1.20]
3.6
stakeholder
organization or individual who obtains investment returns, supply quality, safety guarantees and city
management benefits through the operation and maintenance of utility tunnels EXAMPLE A u t h o r i t y ,
investor, developer, operation provider, maintenance provider, pipeline operator, citizen.
3.6.1
authority
organization that develops, maintains, administers and / or enforces regulations to ensure safety, quality
and performance as well as other important aspects of a utility tunnel
Note 1 to entry: The role of authority sometimes can be performed by the government or land owner.
EXAMPLE Community governmental agency.
3.6.2
investor
organization that invests in the development of a utility tunnel
Note 1 to entry: The financing institution can also be an investor when they provide funding for the development of a
utility tunnel.
EXAMPLE Development bank, commercial bank.
3.6.3
developer
organization that is responsible for the plan, design and construction of a utility tunnel and operation of a
utility tunnel by organizing it in whole, or in part
Note 1 to entry: The developer can delegate utility tunnel operation and maintenance providers to operate and
maintain the utility tunnel.
EXAMPLE Private developer, municipality.

3.6.4
operation provider
organization that is responsible for operating a utility tunnel
3.6.5
maintenance provider
organization that is responsible for maintaining a utility tunnel
3.6.6
pipeline operator
organization that is responsible for operating and maintaining a portion or the entirety of the pipelines
EXAMPLE ICT vendor, water supplier, electricity supplier, gas supplier.
3.6.7
citizen
member of a smart community who benefits from the development and operation of a utility tunnel
4 Benefits to stakeholders
4.1 General
The main relationship among stakeholders is shown in Figure 1:
Figure 1 — Relationship among stakeholders
The operation and maintenance of a utility tunnel covers the stakeholders' benefits involved in the plan,
design, construction, operation and maintenance of the utility tunnel throughout its life cycle. The main
benefits that the stakeholder contributes to the process are as follows:
— improve the level of community governance and operation, to plan and use underground space efficiently,
and to promote the sustainable development for the city authority;
— generate investment income for the investor;
— balance the sustainable development of community construction for the developer;
— realize the safe and efficient operation of the utility tunnel, as well as certain economic benefits for the
operation provider;
— realize the normal operation of the utility tunnel and specific economic benefits for the maintenance
provider;
— ensure the safety of pipelines and meet the energy supply needs for the sustainable development of
smart cities for the pipeline operator;
— save costs for operation and maintenance of utility tunnels;
— ensure smart management in the operation and maintenance life cycle of the utility tunnel.
4.2 Authorities
The authority is responsible for the overall management of the operation and maintenance of the utility
tunnel. Application of this document helps authorities to:
— coordinate the issues and activities in the entire life cycle of the utility tunnel including plan, design,
construction, handover of the operation and maintenance services, smart operation and maintenance,
to promote the formulation of requirements related to smart infrastructure, reduce operation and
maintenance costs, and achieve cost efficiency;
— operate as a "system of systems" to improve efficiency of the smart utility tunnel as an integrated
infrastructure;
— ensure the safe operation of the utility tunnel through efficient distribution and optimized management;
— achieve a better balance of benefits among all stakeholders.
4.3 Investors
The investor focuses on investment returns. Application of this document helps investors to:
— identify relevant risk during the operation and maintenance period by understanding the technical
requirements during the operation period before investing;
— provide a basis for investors to formulate possible operational risk management strategies;
— understand the relevant technical requirements of operation and maintenance, and monitor investment
or loan control more accurately;
— contribute to decision-making on collaborative investment or fund-raising.
4.4 Developers
Application of this document helps developers to:
— identify the relevant requirements during the plan, design and construction stages which can improve
the efficiency and cost control during the operation stage, and increase the developer's income;
— contribute to the systematic development of a smart integrated utility tunnel operation and
maintenance system;
— specify the requirements for the plan, design and construction, and operation and maintenance of the
utility tunnel to the entrusted party.
4.5 Operation providers
Application of this document helps operation providers to:
— develop organizational policies, overall management plans and control requirements for the operations
and maintenance of utility tunnels that suit operation providers’ specific characteristics;
— identify safety management and emergency requirements to help operational safety and risk management;

— adopt new technology to improve the efficiency and profitability of operations;
— guide the evaluation and improvement of the operation level of the utility tunnel;
— ensure a consistent income to contribute to the daily operation and maintenance costs.
4.6 Maintenance providers
Application of this document helps maintenance providers to:
— identify the basic technical requirements and organizational requirements of operation and maintenance
to develop daily maintenance measures;
— identify safety management and emergency requirements to help operational safety and risk management;
— adopt new technology to improve maintenance efficiency and cost control;
— understand the requirements of the maintenance of utility tunnels;
— promote the adoption and advancement of smart operations and maintenance.
4.7 Pipeline operators
Application of this document helps pipeline operators to:
— understand the safety and operation level of the utility tunnels;
— achieve a cost-effective utility tunnel that is financially acceptable to pipeline operators;
— reduce the scheduling waste of pipeline operators, and save resources through data sharing, data
collection and data analysis.
4.8 Citizens
Application of this document improves the living environment for citizens by providing:
— more efficient and reliable infrastructure, resulting in a better quality of life;
— effective operation and maintenance of utility tunnels and the reduction of community carbon emissions.
5 Basic elements and overall requirements
5.1 General
The operation and maintenance of the utility tunnel body, the ancillary facilities, pipelines and the OMMP
are the basic elements of the operation and maintenance of a utility tunnel.
Before the operation and maintenance of the utility tunnel begins, the authority or the developer should
reach an agreement with the operation and maintenance provider. The authority or the developer shall issue
an operation license to the operation and maintenance provider, which includes, but is not limited to, the
operable and maintainable objects of the utility tunnel and the types of pipelines that can be accessed. The
organization, personnel and rules of the operation and maintenance provider shall meet the operation and
maintenance requirements. Relevant documents before the operation and maintenance stage, such as plan,
design and construction stages, including BIM and GIS documents, should be submitted to the operation and
maintenance provider.
5.2 Utility tunnel body
The utility tunnel body consists of ancillary facilities and pipelines, and the space where operation and
maintenance activities take place. The following basic requirements shall be met:
— The design requirements for safety, functionality and durability of the utility tunnel body can be met by
checking the construction acceptance documents of the utility tunnel body.
— The utility tunnel body shall take full advantage of the underground space considering the internal and
external conditions;
— Functional parts of the utility tunnel such as entrances, vents and pipeline intersections, shall
be constructed according to the design requirements and meet the operational and maintenance
requirements. The internal space of the utility tunnel shall be comprehensively determined by details of
pipelines, such as type specification, quantity, installation requirements;
— As a basic requirement of BIM, survey and mapping data of the utility tunnel body shall be obtained before
construction is approved. A BIM+GIS model that meets the requirements of city information modelling
(CIM) should be established. Individuals or organizations who survey and map the construction data
should be trained and authorized to carry out the work;
— When a defect or damage occurs in the utility tunnel body due to material degradation or use of excessive
loads during the service period, it should be recorded as defective and effectively disposed of according
to the predetermined disposal measures.
5.3 Ancillary facilities
The ancillary facilities of the utility tunnel ensure the stable operation of the main body, the internal
environment, pipelines and the safety of operations and maintenance personnel. The following basic
requirements shall be met:
— Facilities for firefighting, ventilation, illumination, monitoring and alarms, drainage, etc. shall be capable
of coordinated control;
— The lighting system shall meet requirements for operation, maintenance and emergency evacuation;
— The system composition, structure and configuration of the monitoring and alarm facilities should be
determined according to the construction scale, the types of pipelines, and the operation, maintenance
and management mode of the utility tunnel;
— Monitoring devices shall be installed for pipelines. For example, combustible gas detection and alarm
devices shall be installed in the cabins containing gas pipelines. Thermal detectors shall be installed
around the electricity cables for fire alarms.
5.4 Pipelines
The pipelines can obtain a stable environment through the operation and maintenance of utility tunnels.
The following basic requirements shall be met:
— During the plan and design stage of utility tunnels, the developer should consider the requirements of
the operation and maintenance of the pipelines.
— The pipeline operator should apply to the utility tunnel operator for access to the pipeline to the utility
tunnel, and provide relevant documents such as the pipeline installation, operation and maintenance
plan. The pipeline can be accessed to the utility tunnel with the permission of the utility tunnel operator.
The pipeline owner shall submit the operation and maintenance schedule and emergency plan of the
pipeline to the utility tunnel operator.
— After the installation of the pipelines into the utility tunnel, the operator shall ensure that the installation
meets the requirements for the operation and maintenance of the utility tunnel.

— The number and type of pipelines entering the utility tunnel should be consistent with the plan and
design specifications.
5.5 Operation and maintenance management platform (OMMP)
5.5.1 The OMMP is a comprehensive system. The system architecture and functions shall include at least,
the following aspects to ensure effective operations:
— the requirements for developing a local smart community;
— the scale of the utility tunnels;
— the specifications for hosted pipelines;
— the mode for operation and maintenance management.
5.5.2 The basic architecture from layer 1 to layer 4 is shown in Figure 2. The system shall include, at the
least, the functions listed below:
— asset management;
— mechanical and electrical equipment monitoring management;
— environmental monitoring management;
— data management;
— inspection and maintenance management;
— a security alarm;
— emergency coordinated control.
Figure 2 — Basic architecture of the OMMP

5.5.3 The platform should allow for safe information exchange among pipeline management units and
relevant information platforms, or reserve a standard information exchange interface. The OMMP should
reserve interfaces to ensure the platform connecting national infrastructure management and pipeline
information networks.
5.5.4 The OMMP’s security architecture shall be aware of local regulations regarding the protection of
information. Measures should be taken to prevent the OMMP and data from attacks, intrusion, interference,
damage, illegal use and accidents, in order to implement stable and reliable operation of the OMMP and data,
and ensure the integrity, confidentiality and availability of the information.
NOTE Local security and confidentiality regulations can apply to the collection, storage, transmission and
exchange of information.
5.5.5 The OMMP should meet the requirements for managing smart cities and integrate with the following
smart technologies to effectively improve the capability, security, reliability, technology advancement of
the system:
— IoT technology;
— big data, machine learning and artificial intelligence technology;
— cloud technology;
— BIM+GIS and visualization technology (see Annex B);
— smart equipment, virtual reality and augmented reality technology.
6 Operations and maintenance
6.1 General
The operation and maintenance of the utility tunnel refers to a series of activities, including planning,
organization, implementation and control, which are carried out during the life cycle of the utility tunnel
body, ancillary facilities and pipelines. These activities can be divided into operations, maintenance and
management. They ensure that the utility tunnel operates safely and provides services to stakeholders.
Operations and maintenance personnel shall have received pre-job training and a qualified certificate.
Personnel, equipment, instruments and operating procedures which are involved in the operations and
maintenance in the flammable and explosive zone shall be aware of the explosion-proof safety requirements.
6.2 Operations
6.2.1 General
In general, operations should include at least, duty, detection, monitoring, routine inspection, safety
operations and financial management.
6.2.2 Duty
Duty arrangements can be performed by the operation and maintenance provider and pipeline operator, and
shall meet the following requirements:
— appropriate duty systems shall be established for operation and maintenance management according to
operational requirements;
— the personnel involved in monitoring, firefighting, power supply and related professions shall be aware
of the related local regulations;

— the utility tunnel body and its ancillary facilities shall be centrally monitored for operational and
maintenance status;
— the image for key locations shall be monitored and recorded in real time, and should be analysed in real-time;
— any operation and maintenance anomaly shall be alerted to the operator, information about relevant
facility anomalies shall be displayed and the anomaly should be disposed in a timely manner.
6.2.3 Detection and monitoring
Detection and monitoring of the utility tunnel body and ancillary facilities shall meet the following
requirements:
— the utility tunnel body and ancillary facilities shall be detected on a regular frequency, and a related
detection report shall be issued;
— the technical indexes of the utility tunnel body shall be detected onsite based on the indexes of technical
information files;
— the detected anomalies of the utility tunnel body and ancillary facilities shall be recorded and analysed
and a repair plan shall be prepared and implemented;
— the monitoring plan of the utility tunnel body shall be prepared according to the geological conditions,
construction technology, structural form, external environmental conditions or safety assessment
results of the utility tunnel;
— the monitoring of the utility tunnel body should be implemented when there are significant changes
in hydrogeology, which can lead to cracks, leakage and other accidents affecting the stability of the
structure;
— the accidents, defects or serious damage of utility tunnels shall be recorded and analysed and a
maintenance plan shall be prepared and implemented;
— detection and monitoring of the utility tunnel body can be made by a third-party, detection and monitoring
of its ancillary facilities can be made by the operation and maintenance provider.
6.2.4 Routine inspection
6.2.4.1 General requirements
The routine inspection shall meet the following requirements:
— The inspection shall be conducted on the utility tunnel body, ancillary facilities, pipelines, the internal
environment and the external environment.
— The inspection personnel shall carry the necessary equipment and take appropriate protective measures.
— During the inspection, the operating status of facilities shall be checked, the inspection notes shall be
recorded and anomalies shall be reported, analysed and handled in a timely manner. Effective measures
shall be taken if an emergency occurs.
— Prohibited activities shall not be conducted within the safety protection zone and the safety control zone.
— The inspection shall adopt the use of manual or IT-based inspection or a combination of both.
— In high-risk zones (e.g. in the gas cabin), unmanned or remote inspection should be implemented to
protect inspectors from potential harm in case of hazards.
— Each inspection should be controlled and an online report submitted, recorded and stored.

6.2.4.2 Routine inspection of utility tunnel body
The inspection of the utility tunnel body can be taken by the operation and maintenance provider, and shall
meet the following requirements:
— The routine inspection shall be conducted on the utility tunnel body, personnel entrances and exits,
material hoisting entrances, emergency exit, ventilator shaft, pipeline branch outlet, inspection channel,
ventilation duct, supports and hangers of pipelines, drainage facilities, and other structures.
— The inspection plan, content and frequency shall be reasonably determined based on the operating
conditions and external environment, and the operation status of the utility tunnel body should be
checked accordingly.
— Inspection records of the utility tunnel body shall include, for example, inspection time, scope, personnel,
defect type, detect degree and defect location.
6.2.4.3 Routine inspection of ancillary facilities
The inspection of ancillary facilities can be taken by the operation and maintenance provider, and shall meet
the following requirements:
— The routine inspection shall be conducted on, for example, firefighting systems, ventilation systems,
power supply systems, illumination systems, monitoring and alarm systems, water supply and drainage
systems and identification systems.
— The inspection plan, content and frequency shall be reasonably determined based on the operating
conditions and external environment, and the operation status of the ancillary facilities should be
checked accordingly.
— Inspection records of the affiliated facilities shall include, for example, inspection time, scope, personnel,
defect type, defect degree and defect location.
6.2.4.4 Support of pipeline routine inspection
The inspection of pipelines in utility tunnels shall meet the following requirements:
— The routine inspection shall be conducted on, for example, pipelines, pipe fitting, supports and hangers
which accompany pipeline construction, and detection and monitoring devices in utility tunnel.
— The inspection and maintenance plan of the pipelines in a utility tunnel shall be developed. The pipelines
in utility tunnels should be inspected regularly and repaired, reconstructed or updated in time. Necessary
measures shall be taken for pipelines that have stopped operating and have been sealed up or scrapped.
— The operation provider should be responsible for the daily inspection of the pipeline in utility tunnels,
and should support each pipeline operator to carry out the professional inspection.
— The operation and maintenance provider shall provide a safe internal environment of the utility tunnel
for the daily inspection of pipelines which are taken by the pipeline operator.
6.2.5 Safety operations
6.2.5.1 General
Safety operations can be taken by the operation and maintenance provider and the pipeline operator, and
shall meet the following requirements:
— the internal environment of the utility tunnel shall meet the requirements of ventilation and lighting for
operation, and the environment shall be kept safe;
— the operation site shall be supervised by specialists, warning signs shall be set up, and the contact with
the monitoring centre should be maintained unimpeded;

— protective measures shall be taken in accordance with requirements for special operations;
— the safety protection zone should be set up within the specific area surrounding the utility tunnel body
in order to protect the safety of the community utility tunnel body. it is prohibited to implement activities
such as stacking, unloading, construction, and pouring of corrosive liquids in the safety protection zone;
— the safety control zone should be set up within the specific area which is in the surrounding of the
utility tunnel body in order to protect the safety of the community utility tunnel body. any construction
activities in the safety control zone shall take into consideration the relevant approval procedures.
6.2.5.2 Personnel security
Personnel entering or exiting the utility tunnel shall be aware of the following provisions:
— All work in the utility tunnel shall be detailed and approved.
— Personnel shall take safety training before being qualified for working in the utility tunnel.
— Entering the utility tunnel alone is forbidden.
— Personnel should check the environment and ventilate the tunnel, and confirm that the environmental
indexes meet the safety requirements before entering the tunnel.
— The personnel entering the utility tunnel shall be equipped with necessary protective equipment,
detection instruments and emergency equipment.
— Except for authorized work with flames or flammable equipment, personnel are not allowed to carry
any flammable and explosive equipment during routine inspection in the gas cabin, and the equipment
...