raytaylor:This makes the decibel rating harder to use as an assessment tool.
Our council uses Db rating too, which is meaningless for low freq noise. Can be really annoying but the council may ignore because it is under their limit.
New Zealand have pretty poor noise control regulations as we recently found out. Took us 5 months to get the neighbours friday night parties stopped.
Part of our problem was that people can make as much 'vocal' noise as they like... including screaming, shouting, drinking games, and profanities into all hours of the night .... as long as they don't play music they can get away with it.
The RMA says people noise is not permitted, but there is not any enforcement action specified for 'people' noise. You can take away a stereo but you can't take away a person as such. Although, I suspect our council were just useless and didn't really have a clue.
Eventually our neighbours started playing music too, and we got an abatement notice slammed on them. After that they moved out and no more parties or fireworks woohoo.
As for the heat pump issue, I'd just call the council and ask to speak to their noise control manager and they can assist with info. You will not be the first.