TOWARDS A STANDARD SPECIFICATION FOR TERRESTRIAL LASER 
SCANNING IN CULTURAL HERITAGE —- ONE YEAR ON 
P. G. Bryan ! D. M. Barber ? and J. P. Mills? 
! English Heritage Metric Survey Team, English Heritage, UK 
paul.bryan@uenglish-heritage.org.uk 
? School of Civil Engineering and Geosciences, University of Newcastle upon Tyne, UK 
d.m.barber@ncl.ac.uk, j.p.mills@ncl.ac.uk 
KEYWORDS: Cultural Heritage, Specification, Terrestrial, Laser scanning, Standards, Archaeology, Architecture 
ABSTRACT 
The development of a specification to standardise the capture, presentation and delivery of point clouds for cultural heritage 
applications is a necessary step in the acceptance of laser scanning as an every day survey technique. For a number of years 
English Heritage, England’s national body for the conservation of cultural heritage, has maintained a specification stating the 
requirements for the capture of metric survey data by photogrammetric, rectified and orthorectified photography, REDM and 
hand methods. The development of laser scanning and its obvious potential in cultural heritage has led to the development of 
a similar set of standards for this new technology. 
This project, through consultation with English Heritage, users and manufacturers, sought to develop standards that were 
relevant and applicable to the instruments currently available for laser scanning. The project also aimed to steer the 
development of laser scanning by outlining to manufacturers and developers the particular requirements of cultural heritage 
survey. Due, however, to the rapidly evolving nature of new technologies it is anticipated that the specification will continue 
to be adapted over the next few years. This paper reports on the document’s development one year on from the project’s end. 
It will provide an example of the use of the specification on a terrestrial laser scanning project in the UK, in addition to 
discussing and summarising the benefits and issues that have arisen. This will include a summary of the economic benefits 
of the specification. It is hoped that the work will lead to an increased use of laser scanning for cultural heritage in the UK, 
in addition to ensuring the expectations of end users are managed. 
1. INTRODUCTION subsequently increase the value of such survey work to 
the end user. Nevertheless, throughout the project the 
This paper describes the development of an addendum to steering committee strived to make the addendum as 
the Metric Survey Specification of English Heritage flexible as possible while still placing firm requirements 
(Bryan and Blake, 2000) covering the collection of on the provision of data. This was a key factor addressed 
survey data by terrestrial laser scanning. It details the by presenting the addendum in two parts. 
work that has taken place since the outline provided by 
Barber et al. (2003) and describes the final draft The scope of the specification was defined before work 
presented to English Heritage in December 2003. began. The term laser scanning covers a broad range of 
Throughout the project the addendum was reviewed by a measurement techniques including airborne LiDAR and 
steering committee of users and providers. It was drafted close range systems. Both of these techniques have been 
in two parts. Part One provides a user guide that gives shown to have applications in recording cultural heritage 
examples of use and provides general guidelines and (Beraldin et al. 1998; Beraldin et al. 2002; Bewley 2003). 
discussion. It is intended that this user guide supports the However, as the project was originally seen as an 
standards provided in Part Two that forms the specific extension of the current metric survey specification, 
contractual requirements placed on the surveyor. For which specifically deals with buildings and small sites 
generic requirements, that is those that relate to any type rather than regions or small artefacts, the addendum was 
of survey, the reader is referred to the existing Metric defined for terrestrial scanners that are most applicable to 
Survey Specification. these scales. This means that data from, for example, a 
close range laser scanner may not be efficiently collected 
One of the most challenging decisions in defining a using the addendum in its current form. Also whilst the 
standard survey specification for a new technology is addendum relates to the scale of survey addressed in the 
deciding the appropriate time at which to undertake such current document it does not attempt to replicate 
a task. Until maturity, new technologies, such as laser traditional products which tend to record the position of 
scanning, often experience rapid development that makes edges, instead concentrating on the recording of surfaces, 
the development of standards difficult. This could result to which laser scanning is more suited. 
in wasted effort or, even worse, lead to a stifling of the 
technology by restricting its application. Nevertheless, it Indeed, the project restricted itself to specifying for the 
was decided that sufficient work had been previously most appropriate methodologies for collecting data and 
undertaken to warrant the definition of a standard survey providing that information in a universal and wel 
specification. Indeed, far from restricting application of documented manner. It did not attempt to specify the 
the technique, it was believed that a specification would processes required to implement data from terrestrial 
actually encourage the use of laser scanning and laser scanning into everyday use. The implementation of 
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