Frequently asked questions

Describes how the Transport Agency manages construction and maintenance noise and vibration to avoid unreasonable effects on communities and individuals.

Describes the sources and impacts of road traffic noise, how noise is measured, the factors that influence noise levels, noise standards and criteria, and how road traffic noise is managed for both new and existing state highways.

Discusses measures for reducing (mitigating) road traffic noise, including barriers, low noise road surfaces, and building acoustic treatments, and how and when the Transport Agency implements these measures. Also described is noise monitoring and assessment, and the circumstances under which noise monitoring is undertaken.

Engine brakes are a type of supplementary braking system provided on heavy vehicles to assist the normal ‘service brakes’ in maintaining safe speeds travelling down hills. The regulation of engine braking and the management of its potential disturbance of nearby communities is described.

Vehicles entering the New Zealand fleet need to meet noise emission requirements at the time of their entry. Once vehicles are in service noise emissions and/or noise control devices may be checked during the warrant of fitness and certificate of fitness process. The NZ Police can enforce ‘excessive noise’ from vehicles on the road.

Reverse sensitivity is the vulnerability of an established land use (state highway) to complaint from a newly establishing, more sensitive land use (new houses and other activities which might be disturbed by noise from a road). Managing reverse sensitivity effects is the joint responsibility of Councils, property owners and the NZ Transport Agency.

The primary impact of road-traffic vibration is perception or ‘feeling’ vibration, which might cause concern or disturbance. Road-traffic vibration seldom reaches levels that could cause damage to buildings or structures.