Categories of Information

The FHWA has identified 14 categories of information regarding the

NTIS. The FHWA seeks comments from our partners and interested parties

on the following questions.

1\. Definition of \`\`Tunnel\'\'

The NTIS would apply to structures receiving Federal-aid highway

funds that meet the NTIS definition of a \`\`tunnel.\'\' What
requirements

should the FHWA incorporate into the definition of a \`\`tunnel\'\'? The
AASHTO T-20 definition of a tunnel is adequate.

A. Should the definition of a \`\`tunnel\'\' contain a minimum length

requirement? Yes, or there should be different requirements based on
length. A relatively short tunnel should not have as stringent
requirements as a much longer tunnel. Tunnels that do not require
ventilation should be excluded from the requirements of the NTIS.

B. Should the definition of a \`\`tunnel\'\' contain requirements other

than tunnel length? No.

C. The National Fire Protection Association defines a tunnel as an

\`\`enclosed roadway for motor vehicle traffic with vehicle access that

is limited to portals.\'\' \\2\\ The American Association of State
Highway

and Transportation Officials (AASHTO) Technical Committee for Tunnels

(T-20) defines tunnels as \`\`enclosed roadways with vehicle access that

is restricted to portals regardless of type of structure or method of

construction. Tunnels do not include highway bridges, railroad bridges

or other bridges over a roadway. Tunnels are structures that require

special design considerations that may include lighting, ventilation,

fire protection systems, and emergency egress capacity based on the

owner\'s determination.\'\' Should the FHWA adopt one of these
definitions

or another definition of tunnel? AASHTO T-20 definition, with possibly
some modifications.

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

\\2\\ NFPA 502: Standard for Road Tunnels, Bridges, and Other

Limited Access Highways Sec. 3.3.38 (National Fire Protection

Association 2007).

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

2\. Inspection Procedures

Inspections should assess the condition of all structural elements

of a tunnel and assess the condition and performance of a tunnel\'s

structural, mechanical, electrical, hydraulic and ventilation systems,

including operational procedures.

A. Should the NTIS adopt the inspection techniques and standards in

the Highway and Rail Transit Tunnel Inspection Manual? Yes, at least as
a starting point.

B. What additional sources of inspection standards should the FHWA

consider? None.

C. Should inspections include evaluation of emergency response and

non-emergency operational procedures? No, however there should be a
requirement for the owner to periodically evaluate these.

D. Are there any special inspection procedures for new tunnels that

should be included in inspection manuals for all new tunnels? None.

3\. Frequency and Types of Inspections

The inspection of highway tunnels likely would include collecting

information on the condition of all structural elements and systems.

A. What tunnel elements and systems should be inspected routinely?
Mechanical, Electrical, Ventilation, Safety and Structural systems.

B. What inspection frequency should be established for these

elements and systems? 2 to 4 year frequency seems reasonable.

C. Should a minimum frequency for tunnel inspection be established? Yes.

D. Is there a need to identify various types of inspections? If so,

what types of inspections should be defined? Yes, in depth -all phases,
interim - a partial more frequent inspection possibly on only some
systems, and special or accident -a response to specific events.

E. Should the frequency of each type of inspection vary according

to the type of inspection? Yes.

F. Should we establish a risk-based frequency to account for the

complexity of each tunnel? Yes.

G. What factors (e.g., age, traffic, length, ventilation, urban or

rural location) should be included in a risk-based frequency inspection

system? The above except for location and include type of construction
and vulnerablility.

4\. Equipment and System Inspection

The NTIS likely would include requirements for inspection

procedures for structural, mechanical, electrical, hydraulic and

ventilation systems, and other major tunnel elements. For several

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of these elements and systems, the inspections could include the

following provisions:

A. The mechanical inspection could consist of verifying the

condition and operation of tunnel mechanical equipment and systems.

Examples of mechanical equipment and systems include, but are not

limited to, ventilation fans, control room air conditioning and

heating, plumbing systems and tunnel drainage and waterproofing

systems.

B. The structural inspection could include suspended ceilings,

structural attachments, lining, exposed rock, roadway slabs, and tunnel

finishes.

C. The safety inspection could consist of verifying the condition

and operation of various safety equipment and systems, such as variable

message signs, overhead warning systems, carbon monoxide detection

systems, fire protection systems, signage, geometry, traffic signals,

and normal operations and emergency response procedures.

D. The security inspection could consist of verifying the condition

and operation of security equipment and systems that are used to detect

and coordinate responses to natural or man-made emergencies. These

systems include video cameras, monitors, alarms, telephones, security

gates, and portal flood gates.

E. The electrical inspection could consist of verifying the

condition and operation of electrical equipment and systems used for

power distribution, emergency power, and lighting.

5\. Qualifications and Required Training of Inspectors

A. Should the qualification requirements for transit tunnel

inspectors contained in the Highway and Rail Transit Tunnel Inspection

Manual be adopted as the qualifications required for Federal-aid

highway tunnel inspectors? Are the qualifications in the Highway and

Rail Transit Tunnel Inspection Manual sufficiently specific for all

tunnel elements and systems? These are probably good starting points.
Certification should be done at a national level. Since these
inspections will probably be contracted, for states with a few tunnels
it would be impractical to certify the inspectors for all consultants
interested in performing this work.

B. What education and training should be required for tunnel

inspectors? Should the NTIS incorporate a requirement for periodic

training for tunnel inspectors? A comprehensive tunnel inspection course
should be developed dealing with all aspects of tunnels. This would be
required for all inspection team leaders, and then additional
requirements should exist for the various disciplines required. For
example, someone inspecting the electrical system might be required to
have a degree in electrical engineering or be a licensed electrician.
There should be some type of continuing education requirement for the
tunnel inspectors.

C. What experience should be required for tunnel inspectors? Should

there be multiple levels of qualifications depending upon the role of

the team member (i.e., leader, inspector) and the type of inspection?
The type of inspection should definitely be a factor, as well as the
leader versus inspector.

6\. Recordkeeping

A. Should States be required to keep records of all highway tunnel

inspections performed within the State? If not, where and with whom

should the inspection records reside? The tunnel owner should be
required to maintain the inspection records.

B. Are inspection record requirements such as those contained in

the Highway and Rail Transit Tunnel Inspection Manual sufficient for

the NTIS? Yes.

C. For how long should tunnel inspection records be maintained? For the
life of the structure.

7\. Rating

A. Should the NTIS incorporate a condition-based rating system for

Federal-aid highway tunnels, under which the tunnels in the best

condition receive a high rating and the tunnels in the poorest

condition receive a low rating? Yes.

B. Should a tunnel rating system be the basis for possible funding

decisions? Yes.

8\. National Tunnel Inventory Database

A. What tunnel data elements should be collected for all Federal-

aid highway tunnels (e.g., tunnel name, age, length, finishes, width,

height, number of lanes, ventilation, truck traffic, automobile

traffic)? Should be similar to the NBI requirements. Florida has one
highway tunnel which we currently report as part of the NBI. This should
meet the requirements for reporting.

B. How often should data be collected and reported? Data should be
collected based on the inspection cycle. It could be reported annually.

C. Should this data be reported to the FHWA? Yes.

D. Should a tunnel be identified using a tunnel inventory number

(TIN) in a manner similar to how bridges are identified under the NBIS?
Yes.

E. What criteria should be used to assign a TIN? State determined.

9\. Organization of Inspection Teams

A. How should the inspection teams be organized?

B. Should inspection teams be established with differing levels of

responsibility? Yes, there could be separate teams for
mechanical,structural, electrical and ventilation.

C. Should one person on the team have overall responsibility for

the program? Not necessarily, there could be a single person (ideally a
professional engineer) responsible for the overall inspection effort who
would sign and seal the inspection report.

10\. Technical References

What technical publications, if any, should be incorporated by

reference? The "Highway and Rail Transit Tunnel Inspection Manual"

11\. Quality Control/Quality Assurance (QC/QA)

Should QC/QA procedures similar to the procedures required under

the NBIS be implemented for the NTIS? Yes.

12\. Cost of Inspections

The FHWA requests information regarding the costs associated with

tunnel inspections, particularly the typical inspection costs per

linear foot of tunnel. Florida has one tunnel (a single divided barrel
864 foot long), carrying 4 lanes of traffic. The inspection costs
(mechanical, electrical and structural) are approximately \$10 per
linear feet per barrel.

13\. Tunnel Repairs

The FHWA requests information associated with tunnel rehabilitation

projects (e.g., costs of repairs, dates of work, scope of work). None
readily available.

14\. Research

The FHWA and others have conducted extensive research related to

tunnel design, construction, rehabilitation, and inspection. The

following is a list of research projects related to tunnel safety that

either have been conducted or are ongoing.

A. The Memorial Tunnel Fire Ventilation Test Program

The FHWA and the Massachusetts Highway Department sponsored the

Memorial Tunnel Fire Ventilation Test Program (MTFVTP) in 1993. This

research project consisted of a series of full-scale fire tests

conducted in an abandoned road tunnel. As part of this project, a total

of 98 tests were conducted considering various smoke management

strategies. Various tunnel ventilation systems and configurations of

such systems were operated to evaluate their respective smoke and

temperature management capabilities. These tests generated a

significant database relevant to the design and operation of road

tunnel ventilation systems under fire emergency conditions.

Proper ventilation of highway tunnels is necessary to provide a

safe and secure environment for the traveling public during normal and

emergency situations in tunnels. The NTIS would set standards for the

inspection of tunnels, including ventilation systems, to assure safe,

reliable and efficient operation.

B. Prevention and Control of Highway Tunnel Fires

The FHWA sponsored a study related to tunnel fires in 1984. This

study investigated: (1) Steps that can be taken to reduce the risk,

damage, and number of fatalities from fires in existing and future

highway tunnels; and (2) effects of unrestricted transport of hazardous

materials through tunnels. This study examined the history of highway

tunnel fires to determine the design and operating features that

influenced ignition and spread of fire; detection, alarm transmission,

and notification of appropriate authorities; response; control,

extinguishment, and suppression; and resultant fatalities and damage.

Operators in major domestic highway tunnels were interviewed about

tunnel fires, and their responses were tabulated and compared. The

study examined the procedures used in, and results of, several tunnel

fire tests and evaluated their recommendations in light of historical

evidence and operating experience concerning tunnel fires. This study

led to the development of comprehensive design and operating

recommendations for prevention, detection, alarm, notification,

control, extinguishment, suppression, and survival. The report is

available at
[[http://ntl.bts.gov/lib/2000/2400/2416/708.pdf]{.underline}](http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://ntl.bts.gov/lib/2000/2400/2416/708.pdf).

Tunnel components that relate to the prevention, detection, alarm,

notification, control, extinguishment,

\[\[Page 68368\]\]

suppression, and survival systems need to be maintained and inspected

to ensure these critical systems are working properly at all times. The

NTIS could set the standards for inspection of these key components.

C. Underground Transportation Systems in Europe: Safety, Operations,

and Emergency Response

In 2005, the FHWA, AASHTO, and the National Cooperative Highway

Research Program (NCHRP) sponsored a scanning study of equipment,

systems, and procedures used in tunnels in several countries (Austria,

Denmark, France, Germany, Italy, Norway, the Netherlands, Sweden, and

Switzerland).

The scan team learned that Europeans are conducting research to

develop innovative design and emergency management plans that consider

how people react in tunnel emergencies. Because motorist behavior is

unpredictable in tunnel incidents, Europeans make instructions for

drivers, passengers, and tunnel operators as straightforward as

possible.

The team\'s recommendations for U.S. implementation include

conducting research on tunnel emergency management that includes human

factors; developing tunnel design criteria that promote optimal driver

performance during incidents; developing more effective visual,

audible, and tactile signs for escape routes; and using a risk-

management approach to tunnel safety inspection and maintenance.

The report states that \`\`only limited national guidelines,

standards, or specifications are available for tunnel design,

construction, safety inspection, traffic and incident management,

maintenance, security, and protection against natural or manmade

disasters.\'\' The report also notes that, \`\`\[t\]hrough knowledge of
the

systems and the structure gained from intelligent monitoring and

analysis of the collected data, the owner can use a risk-based approach

to schedule the time and frequency of inspections and establish

priorities.\'\' The final scan report is available on at
[[http://]{.underline}](http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://international.fhwa.dot.gov/uts/uts.pdf)

[[international.fhwa.dot.gov/uts/uts.pdf]{.underline}](http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://international.fhwa.dot.gov/uts/uts.pdf).

The NTIS could assist owners in establishing priorities for the

management of their tunnel inventories.

D. NCHRP Project 04-37, Long-Term Performance of Epoxy Adhesive Anchors

The FHWA and AASHTO have initiated a NCHRP project to investigate

the long-term behavior of epoxy adhesive anchors. Common transportation

applications for epoxy bonded anchors include bridge widening, concrete

repair and rehabilitation, barrier retrofitting, utility installation

on existing structures, and tunneling. Despite widespread use, the

suppliers of these systems provide little guidance on how the adhesives

perform under sustained, long-term loading.

The NTIS could set standards for inspection of adhesive anchors, as

well as all other structural components in tunnels.

E. NCHRP Project 20-07/Task 261, Best Practices for Implementing

Quality Control and Quality Assurance for Tunnel Inspection

In response to the NTSB\'s preliminary safety recommendations

resulting from the Central Artery tunnel ceiling collapse in Boston,

the FHWA and AASHTO initiated this NCHRP project. The objective of this

project is to develop guidelines for owners to use in selecting quality

control and quality assurance practices for tunnel inspection,

operational safety and emergency response systems testing, and

inventory procedures to improve the safety of highway tunnels.

F. FHWA Control of Highway Tunnel Fire Workshop

In response to OIG\'s August 2007 report on the CAT Project\'s Stem

to Stern Safety Review, FHWA conducted a workshop on \`\`Control and

Modeling of Fires in Highway Tunnels.\'\' The workshop was held on July

22-23, 2008, and was attended by national and international experts in

tunnel design, tunnel operation, emergency response, and fire modeling.

The objectives of the workshop were to: Share information about gaps in

the current standards for design of tunnels; share best practices for

response to incidents; identify the parameters needed to start a pilot

program to model fires of 60 Megawatts and higher in highway tunnels;

and identify other research needs. The results of the pilot program

could be used to update the current national tunnel standards. The

proposed NTIS could ensure that all systems needed for highway tunnel

fire protection are maintained, inspected and repaired on a timely

basis.

We welcome information regarding other existing or ongoing research

related to tunnel inspections. What additional research should be

undertaken? Many tunnel structural elements are not visible and the
condition of these elements such as tunnel liners have traditionally
been deduced by water leakage, efflorescence, etc. Therefore, research
is needed to develop, evaluate and recommend specific non-destructive
inspection evaluation methods and practices.