Any notion that mobile phone cell sites are simple and quick to construct, just masts with a few antennas stuck on top, is dispelled when riggers from Downer appear in safety harnesses which look like something mountaineers wear.
We're at the Western Springs stadium where Downer is upgrading an existing Vodafone 4G LTE cell site with 5G equipment from Nokia ahead of the December launch of the next-generation mobile technology.
Everyone has to wear appropriate protective equipment on the site, including Vodafone's Thaigan Govender, lead engineer in charge of the telco's 5G radio upgrades around the country.
South Africa-born Govender's official title is Radio Access Network Manager. He leads a diverse, multinational team of engineers at Vodafone who work with Nokia techies in Australia, China and Europe to ensure the 5G upgrade goes smoothly.
The Western Springs cell site is sizeable and safety is paramount. It has had 10m scaffolding erected around it. There's a safety briefing to make everyone aware of the multiple hazards on site, with a particular warning to stay out of the exclusion zone around the mast– to protect the team.
"We are going to add the 5G antennas to the tower and redirect the 4G ones to make space for the new gear," Govender explains.
There's much more to it than that, of course, including connecting new data transmission circuits to the systems base of the tower to handle the much quicker wireless broadband speeds 5G is capable of. While they're at it, 4G equipment at the site will get a refresh with newer (and smaller) 4.5G gear, providing better performance.
New control systems to manage 5G aerials have already been slotted into the racks at the foot of the tower, with small high-speed fans whirring as an engineer (who has upgraded the software in them via his laptop) reboots the gear.
Thanks to power-saving advances for both 4G and 5G, the cell site can be cooled with fans and doesn't require air conditioning to prevent electronics from overheating.
Daniel Kruger from Downer says his crew has roughly one week to complete the upgrade but, this being New Zealand, there's always a risk that the weather puts a spanner in the works. Rain means work has to be halted, ditto winds over 12m per second. Luckily,
today's a sunny day and, although the southerly is nippy, it's not strong enough to halt work complex enough when undertaken indoors – and here we are at the mercy of the elements.
Asked how long the ruggedised Nokia equipment is expected to last, Govender says at least 10 years: "We'll probably upgrade it sooner, as new technology becomes available," he adds.
The first roll-out of Vodafone's 5G network uses the first-generation Non Standalone mode or NSA. That uses the existing 4G Long Term Evolution (LTE) network as a control layer, able to tell devices that 5G is available and switch them over if they're compatible with the newer technology.
Over the next couple of years, fully standalone 5G that doesn't require 4G will be rolled out across mobile networks and devices, once the government sorts out the radio spectrum auction and optimising current allocations among providers.
Western Springs is home to many a large event and Govender says the site can currently handle up to 3000 users simultaneously attached to it, pushing some 1000 gigabytes of data per hour. The 5G upgrade will bump up those numbers by two to three times.
He won't say how much the new equipment costs beyond "lots" – and that the cost and complexity of installation and managing cell sites is one reason why Vodafone spaces them 1-2km kilometres apart.
"We don't need to build 5G sites every 200m like some people have wrongly suggested or cut down trees," Govender says.
Some of the opposition to 5G involves wild claims that the radio signals it uses are harmful. This despite thousands of studies over the past two decades that have found no ill effects from the relatively weak non-ionising electromagnetic radiation used by mobile networks – not to mention wi-fi adapters and TV/radio stations.
One irony lost on those opposed to the 5G roll-out is that the new technology is specifically designed to do more with less power: "5G uses a technology called active antennas and beamforming; that enables a lot less radio energy and power per gigabyte of traffic than current 2G, 3G and 4G technologies," Govender says.
The shaped 5G beams from the active antennas track individual devices and follow them around as people move; 4G transmission tech doesn't have the smarts to do that.
As a result, 5G is more efficient and less wasteful while providing higher performance and allowing many more users to be connected to each site than before – all of which reduce the amount of radio-frequency energy being used, Govender explains.
In other words, if "wireless radiation" is such a worry (and there's no reason for it to be), those concerned about it should push for the network to be upgraded to 5G sooner rather than later – and not fight it.