FAQs Health & Safety
- What about the health effects from transmission lines?
- Does Transpower have a fund to cover possible future health effects?
- What recent advice has Transpower considered on the health effects of living and working near transmission lines?
- How big an earthquake (ie on the Richter scale) can transmission towers handle?
What about the health effects from transmission lines?
Transpower relies on advice from independent experts and the Ministry of Health in relation to electric and magnetic fields from power lines and health effects.
In order to protect against established health effects, Transpower meets the guidelines set by the International Commission on Non-Ionising Radiation Protection (ICNIRP). These are endorsed by the World Health Organisation and recommended for use in New Zealand by the Ministry of Health.
Does Transpower have a fund to cover possible future health effects?
Transpower has no fund set aside to cover possible future health effects. Transpower meets the guidelines set by the International Commission on Non-Ionising Radiation Protection (ICNIRP). These are endorsed by the World Health Organisation and recommended for use in New Zealand by the National Radiation Laboratory, part of the Ministry of Health.
What recent advice has Transpower considered on the health effects of living and working near transmission lines?
Transpower closely monitors engineering, medical and scientific research regarding electric and magnetic fields. Transpower also participates in the New Zealand Interagency Committee on the Health Effects of Electromagnetic Fields which regularly reviews research. In relation to the health effects listed, Transpower relies on advice provided by internationally renowned experts and the NRL (a unit of the Ministry of Health).
There are studies undertaken all the time on a connection or the lack of a connection between electric fields/magnetic fields (EF/MF) and health effects. It is considered that available data has not provided a basis for setting exposure restrictions to protect against health effects such as those listed and this conclusion is consistent with international experience. Nevertheless, Transpower will follow the ‘precautionary principle’ which includes measures such as the reverse phasing of conductors.
How big an earthquake (ie on the Richter scale) can transmission towers handle?
Seismic loading is not a key design issue for transmission towers and consequently there is no easily quoted “Richter scale capability”.This is because damage in earthquakes is related to the mass that is being vibrated, and by comparison to buildings, transmission towers are very light. In addition, they are made of steel which is an extremely ductile material, in a bolted arrangement, providing structural flexibility. Finally, conductors (ie the wires) tend to act as dampers, further reducing any effect from the vibration.