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2 Introduction
2.3 Planning a Survey
Surveys will vary greatly depending on the type of terrain, accessibility, condition of the pipeline, type of pipeline and coating
type.
The first step of undertaking any survey should be to obtain information about the pipeline stretch to be surveyed. More work
at this stage may well save time and effort later. Obtaining maps showing route information, CP stations, sacrificial anodes and
cross bonding points will significantly help.
The transmitter should be capable of transmitting from one CP station to another, so although not necessary, plan to have
the previous and after CP stations disconnected from the pipeline's stretch to be surveyed. Remember that the pipeline is not
protected while the survey is being undertaken so CP stations' unnecessary downtime should be avoided.
Choose the survey interval to match the condition of the pipeline. In areas where the coating is inferior a survey interval of as
little as 10m may be desirable. However, if the coating is in excellent condition and the distance between CP stations is many
km, it may be better to choose a survey interval of as much as 200m. Taking measurements at large intervals will enable the
surveyor to assess the pipeline's condition quickly and subsequently identify areas requiring further inspection at closer survey
intervals or detailed analyses using the A-frame Fault Finder accessory.
