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Frequently Asked Questions

What is utility location?

Utility location is a general term used to describe the process of finding and marking underground services and objects. It is often also called cable location, or service location.

Buried services include utilities such as phone, power, water, gas, sewer and stormwater as well as less commonly known services like fuel supply lines, cable TV, and underground storage tanks.

How the services are traced depends on the type of service to be found and the environment in which the service is buried.

Also, how the location of a service is communicated depends on the requirements of the client. 
In its simplest form, the service position and depth is marked on the ground with temporary marking paint. If the client needs something more formal, the location of services can be surveyed and provided in the form of a plan or drawing.

Can all services be located?

How easily a service can be located is dependent on a variety of factors. Some of the things that determine whether a service can be traced are:

  • the type of service and what it is made of - Services that have a metal component such as power cables, older copper phone lines, iron manhole covers, cast iron gas or water mains can often be more easily located. Non-metallic services such as plastic or PVC pipes, old clay or asbestos cement pipes, and fibre optics can limit the methods of location,
  • what other services are close by - When services are bundled together, or there is a large number of services in close proximity then it can sometimes be difficult to differentiate between individual services without actual digging, and
  • underground service depth - Common services, such as power, gas, and telephone were often buried at a consistent depth, although this cannot be relied on when locating. Depth below 1.5 metres used to be uncommon for these services. Some services, such as sewers and stormwater, will be buried at a much greater depth and are much hard to find. Special techniques will be required to locate and identify deep services.

What is Ground Penetrating Radar?

Ground penetrating radar (GPR) is a technology that uses radio waves to identify objects underground. Different frequency radio waves can be directed into the ground so that objects underground reflect back signals to the receiver at ground level. Objects underground such as cables or pipes have a specific appearance that a trained operator will recognise. GPR can help locate and identify underground services that can't be found by other means such as electromagnetic (EM) detection.

Many factors influence the quality of GPR output, and its use may not be appropriate in every situation. Certain soil types, high water tables, and the characteristics of the underground service all affect how successful GPR will be.

How will services be shown on the ground?

Generally, services will be marked on the ground to show where they have been traced using temporary marker paint.

Specific colours and symbols are used to indicate the different types of services. 

The Department of Labour (OSH) published the accepted colours and symbols in the Guide for Safety with Underground Services in 2002.

ULS follows this convention for marking underground services. You can find a copy of the guide here.

What is AS5488?

AS5488 or Australian Standards AS 5488 - 2019 Classification of Subsurface Utility Information is a standard that establishes a framework for describing the information relating to underground services and the different levels of quality that are possible with the different methods that a service might be located and marked.

The standard defines levels of quality that range from a low or less accurate service location (Quality Level D) through to the best or most accurate level (Quality Level A).

In general, ULS works to a Quality Level B which involves an active method of locations unsing electromagnetic (EM) detection. Ground Penetrating Radar can be used for locating but under AS5488 it cannot be used to achieve a Quality Level B classification.

Each Quality Level has a degree of accuracy that defines the margin of error that can be expected in the horizontal and vertical position of a recorded underground service.

Do you have terms and conditions?

Yes, terms and conditions cover all of the work we complete. All professional locating companies should have Public Liability and Professional Indemnity insurance. To meet the requirements of these policies, ULS has a set of conditions that apply to each job.  

Our terms also cover fundamental business terms such as payment terms, penalties, invoicing, etc.

You can read more about the current terms and conditions here

When you book a job with ULS, you will receive a confirmation email that contains our current terms and conditions agreement.