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Trials of ARMs or ATs may be carried under an approval trial agreement between the undertaker and the authority.
This section outlines a scheme under which trials of ARMs and ATs must be carried out. A9.5.5 gives general guidance relating to the organisation of an approval trial. A9.5.6 describes special conditions relating to the scale of an approval trial and its effect on organisational and reporting matters. A9.5.7 outlines the intended duties of each party within the approval trial. A9.5.9 to A9.5.11 provides a list of headings that describe the key requirements and stages of an approval trial. The headings are considered to represent the minimum essential information required to ensure that the approval trials are carried out in a controlled and agreed manner. The additional information under each heading is for guidance only. The parties to an approval trial (normally an undertaker (who would generally initiate or request the trial) and an authority) may, by agreement with the other party, add, amend or omit any details that do not affect the legal standing of the agreement.
When an ARM or AT has been approved by an authority following a successful trial, the undertaker can provide another authority with the trial data and ask permission to use the ARM or AT in its area. An ARM or AT trialled and approved by one authority must be accepted in different authority areas unless there is a reasonable engineering concern that requires local validation (for example, difference in type of road, pavement construction, position of the trench, etc.). Authorities can, within reason, request additional information if they have valid engineering concerns. If the undertaker is unable to satisfy the request for additional information, additional trials may be necessary.
ARMs and ATs can be used without trials if an authority agrees. However, where no trials have taken place, there is no requirement for another authority to accept the use of those ARMs or ATs.