Transactions on the Built Environment vol 34, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509
Use of computer databases to manipulate safety
information
Keith J Watson
e-mail: http://www. railtrack. co. uk
Abstract
Spread sheets and simple manipulative software tools have been developed to
monitor particular elements of the Railtrack Safety Management System (SMS),
including for example hazard management, accident investigations, accident data,
track quality, compliance to standards.
By careful definition of the data, the format in which it is to be collected, and
adherence to robust management systems, the applications described in this paper
demonstrate that simple computer based tools can be effective elements of a
company's safety management system.
1
Introduction
Railtrack pic is the owner and operator of the principal UK railway
network and sells access to the Passenger and Freight Train Operating
Companies. It maintains and renews the network through contracts
with suppliers. There is a central HQ with seven outbased Railtrack
Zone Directors who have prime responsibility for the day to day
management of the company, including the operation of the Safety
Management System (SMS) and the management of the contractors
who maintain or renew the railway.
Transactions on the Built Environment vol 34, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509
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Railtrack's Railway Safety Case (RSC) contains a description of its safety
management system (SMS), which is used to control the safety risks
associated with its undertaking. There are 19 components of the SMS,
each one of which details the policy that the particular component is
intended to achieve, the arrangements to achieve it including linkage into
individual managers' safety responsibilities, and how it will be
monitored.
Railtrack's legal responsibilities with respect to its RSC are governed by
the Railway (Safety Case) Regulations 1994. The Regulations require the
systems by which Railtrack manages its safety responsibilities, including
the interfaces between itself, Train Operating Companies and its
contractors to be described in an RSC. Once accepted by the Her
Majesty's Railway Inspectorate, compliance with the RSC is a legal duty
upon Railtrack and is an important component of Railtrack's operating
licence issued by the Office of the Rail Regulator.
The paper describes some of the computer based tools that have been
developed to produce relevant safety information and enable Railtrack to
discharge its SMS responsibilities.
2
Zone Hazard Directories
A hazard is a state or condition at a particular location of a permanent or
semi-permanent nature which could give rise to an accident. A risk is the
product of likelihood and magnitude of an accident arising from a
particular hazard. Zone Directors are required by way of a mandatory
Railtrack Line Standard to collect and maintain a list of Zone Hazards
and to ensure that this information is made available to Railtrack
employees, and implement appropriate controls to ensure that the
associated risks are minimised to as low as reasonably practical.
(ALARP). By virtue of the Health and Safety at Work Act 1974 and the
Construction Design and Management Regulations 1994, hazard
information must also be passed onto Contractors so that can they take it
into account in devising safe systems of work.
Initially Zone Directors collected and published this information in paper
format in the 'Zone Hazard Directory'. Each document is sizeable, for
example the Directory covering one Contract area in Scotland contains 77
Transactions on the Built Environment vol 34, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509
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95
pages and over 38,000 pieces of safety information. This led to problems
of:• handling massive amounts of data and manipulating it to
extract useful information,
• updating data in real time,
• distribution of the Directory in a controlled manner to those
who required an up to date version at all times.
It was therefore decided to create a Microsoft Access database for each
Zone to contain the hazard data and to access it using a programme
written in Visual Basic. The system, which is called HAZARD, is
designed to run on the local area network (LAN) and also on personal
computers as a complete application. Neither Microsoft Access, nor
Visual Basic need to be installed for the application to work remotely,
therefore making it easy to distribute and use by organisations such as
contractors who do not have access to the LAN. In the latter case an
export facility enables a contractor to be given a diskette containing a
current copy of the HAZARD system which will also permit
manipulation of the data. To ensure accurate recording, the standard
features of Windows are used, with in many cases built in validation rules
to prevent the entering of erroneous data within a text box, menus and
drop down lists. In addition a comprehensive Help System using the
standard Windows help interface application is provided. Within each
Zone a HAZARD directory editor has been appointed with the
responsibility for managing the system, entering hazard details, providing
outputs etc.
To increase the versatility of the HAZARD system, it contains not only
hazards, but also related information such as authorised walking routes
and access points (both foot and vehicular) pipelines and buried or
overhead utilities, Green Zone availability (when train movement can be
stopped at certain times for personal track safety protection) and Red
Zone prohibitions (locations where personnel are never allowed on the
track whilst trains are moving).
3
EAZIAL
HAZARD has been linked electronically to a front end system called
Transactions on the Built Environment vol 34, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509
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Computers in Railways
EAZIAL (Easy Access Infrastructure Asset Log) which provides a
graphical presentation and access to the databases of the infrastructure
engineers. Much of the detail has however been converted into 'plain'
English for ease of understanding and extensive use is made of the
display of information on track diagrams or maps. This feature assists
both the engineers in their maintenance and renewal programming, and
the planners who are responsible for granting access to the rail network
by the Train Operating Companies and the maintenance and renewal
contractors. EAZIAL operates as a front end tool to gain access to
supporting databases without the operator needing to know how or where
these databases are stored. To operate EAZIAL a diagram of the railway
is displayed. Access to a supporting database is achieved by selecting a
specific geographical location, either by zooming in on the map, or by
selection of a station name, junction name or selection of the track
mileage. Once an appropriate area has been selected, choosing from a
menu will display a range of track side features, with an accuracy on a
scaled map to one yard (0.914m).
Databases accessed contain
information on signals, points, level crossings, bridges, stations,
electricity supply equipment, telecommunications equipment and hazards.
The output from the system is illustrated by the two examples below,
which show the main line within East Anglia Zone and an expanded view
of the circled area.
File
Zoom
Options
Seek
Show
Utilities
Reports Help
I
ShowJELR
EAZIAL - Example showing a route diagram for East Anglia Zone
Transactions on the Built Environment vol 34, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509
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Display
Seek
Utilities
Zoom
Selected mash
1013.0000
97
Reports Help
|ois.oooo
Cheshunt
M196T
C7
EAZIAL - Example showing circled area in greater detail
Note: The icons on the tool bar give access to various databases
4
Monitoring of Indicators for the SMS
Railtrack's SMS requires the use of both pro- active and reactive
indicators to monitor safety performance. Pro-active indicators measure
the achievement of objectives and the extent of compliance with
standards. Reactive indicators monitor accidents, ill health, incidents and
other evidence of deficient health and safety performance such as hazard
reports.
Pro-active indicators have been used by Railtrack for a number of years.
Examples which are currently in use include numbers of safety tours
undertaken by management, amount and timing of induction training
compared to standards, numbers of planned inspections compared to plan,
number of contractor monitoring checks etc. These produced large
amounts of data within each Zone and therefore it became essential to
develop suitable spread sheets and appropriate software to show trends
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and provide useful management information. Below is an example of the
output from the system for planned inspections.
ACHIEVEMENT BY DIRECTORATES FOR 3rd QUARTER
NATIONAL THEM)
§3000
• No. Taken Pbce
-% Compared to Ha
Action
When
Planned Inspections
No. of planned inspections done and % of total planned
By ensuring that information from each Zone to HQ is reported
electronically in exactly the same format on a suitable linked spread
sheet, the quadrant report above can be generated which shows each
Zone's performance in the upper left hand quadrant, and that for Railtrack
as a whole, for the year to date, in the upper right hand quadrant. In the
lower quadrants are shown any commentary and key action points.
Presentation of the information in this way enables Directors and
managers to visualise progress made, how they are doing compared to
others, and facilitates the determination of what else needs to be done. It
is a simple matter, if desired, to also set targets and show these
graphically on the quadrant.
The system is sufficiently flexible to allow for organisational changes.
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Thus at Zone level, up to 10 different Zone managerial organisations can
be selected, the results of which for the period concerned can be
displayed in the upper left hand quadrant. The overall Zone performance
for the year to date is shown in the upper right hand quadrant.
The key to success with the process was to first of all agree within
Railtrack which components of the SMS were to be monitored using an
indicator, and then to agree robust definitions for each one which could
not be interpreted in different ways by each Zone. Finally it was essential
to brief in the new system to ensure that management were properly
aware of what the indicator was showing and how to use the tool. It is
true to say that there is a lot of safety data available, but not necessarily
sufficient safety information. Use of this linked spread sheet reporting
system minimises clerical input by avoidance of data re-keying and
presents managerial information effectively.
5
Tracking Progress of Formal Inquiries
A Formal Inquiry is held for the more serious accidents or near misses
and involves a panel of representatives from the parties involved in the
accident undertaking the investigation, often under an independent
chairman. It is important that the process of Inquiries is monitored by
Railtrack HQ, and that lessons learnt in the form of recommendations are
promulgated once approved. This is achieved by a Microsoft Excel
spreadsheet which enables information to be readily extracted to show
whether the Inquiry is complete, which departments are considering
recommendations, whether they have been accepted or rejected etc.
Use of the system has enabled greater focus on improving the quality and
speed of production of the reports and tracking progress of the
recommendations.
6
Monitoring of Track Quality
Railtrack uses specially equipped track recording vehicles (TRY) to
monitor how effectively its contractors maintain the track to standards
laid down in the contract. The TRY monitors a number of different
parameters concerning the track which would affect the safety of rail
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vehicles, such as the alignment, gauge, twist and the vertical profile of the
rail surface. These are compared to the threshold values specified in a
Railtrack Line Standard. In respect of vertical profile and alignment the
Standard states target values of standard deviation for every eighth of
quarter mile for each speed band, below which 50%, 90%, and 100% of
the recorded standard deviations should fall. Maximum values, known as
'super-red eighths', are those which, if exceeded are subject to remedial
action or a speed restriction. Exceedances at particular locations to the
Standard's requirements (e.g. a gauge fault ) are known as L2 faults.
Much of the 12,000 miles of track are traversed at least once every 6
months by the TRY, and in consequence a lot of data is collected.
After each run of the TRV the information is down loaded onto a
mainframe computer, from which data is extracted and processed into the
format shown below using a simple computer programme.
Track Quality Histograms from a typical Contract Area
This chart shows a contract sub area where there has been some changes
in track quality. The 3 charts show at a glance how the track quality
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standards for worse top (wt), alignment (al) and mean top (mt) have
changed since April 1994 using either a 35m filter for eighth mile track
sections or a 70m filter for quarter mile track sections. The latter is used
for track with a line speed over 70mph.
It can be seen from the upper chart that generally the contractor is
achieving a higher standard than is required for 50% of the track in all
categories. However the targets for 100% have not been met, nor have
those for 90% in all categories except for a!35. The bottom left hand
chart shows the number of L2 exceedances per mile, and the bottom right
hand chart the percentage of failures for which action had to be taken by
the contractor.
These charts enable Railtrack contract managers to monitor the
effectiveness of the contractor over time, it being a very simple matter to
change the computer programme to show the change since the last run of
the TRY.
7
Local initiatives
There is extensive use of databases at Zone level to hold safety data and
to manipulate it to extract useful information for managerial action.
Establishing such systems is facilitated by zonally based IS technology
personnel.
An example is the access database developed on the Great Western Zone
to monitor contractor performance. Links within the spread sheets allow
pre-determined criteria to be traced by contractor, contract, date, type or
any combination of these. The system has improved the dialogue
between project managers and their contractors, through the provision of
an additional tool to manage the contracting relationship.
Where local initiatives are seen to offer national benefits they will be
adopted across the organisation following development by IS personnel,
user consultation and trials. Both HAZARD and EAZIAL had their
origin in a zone system.
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Conclusion
Railtrack is making extensive use of spread sheets and readily available
simple programming tools to present complex data in a way that
facilitates the management decision making process. The examples
illustrated in this paper have been selected from a wide range currently in
use within Railtrack. The keys to success lie in ensuring that the end
users are fully consulted to establish their needs, defining precisely what
data is to be collected and in what format.
At all times it must be remembered that information produced by the
system is only as good as the quality of data input. Errors are reduced by
keeping definitions straightforward, minimising data input as far as
possible and building in error trapping regimes. Experience with a large
devolved organisation such as Railtrack has shown that people will
interpret instructions or definitions in unexpected ways unless this is done
and properly explained to those who have to collect the data. Finally it is
important that systems are designed to be flexible and allow for
modifications to be readily built in. There is a trade off between the time
taken to develop the perfect system and the early introduction of simple,
but fit for purpose systems.
In this manner Railtrack uses simple computer based tools to assist in
monitoring both pro-actively and reactively the effectiveness of the
processes and systems to achieve compliance to its SMS.