A handful of anti-5G protesters picketed Spark's Auckland head office on Thursday. They claim the technology is not safe and is being rolled out without proper consultation.

Earlier in the week, the Prime Minister's chief science advisor, Professor Juliet Gerrard, set up a website to address some of the fears.

The introduction page to the 5G in Aotearoa New Zealand site makes it clear:

"The currently available scientific evidence makes it extremely unlikely that there will be any adverse effects on human or environmental health."

The site describes the characteristics of millimetre waves used for 5G. It points out they can cause heating, but not enough for this to be noticeable. It also covers the security fears of 5G which, because it is more dependent on cloud computing, may involve more risks.

Elsewhere the site covers fears that 5G may cause cancer: the risks are extremely low and there has been no evidence to date.

Many anti-5G campaigners complain of other ailments including headaches and sleep problems. The site says: "Neither short nor long term studies have shown conclusive evidence of any of these or other health effects."

Radio frequencies used for 5G are in the non-ionising part of the spectrum. This means they don't break molecular bonds, or more to the point damage human cell tissue.