New Zealand has some of the sweetest, purest, clearest clean air anywhere in the world.
Most of the time.
In most places.
This is the continuing story of those other times and places.
New Zealand is harbouring four guilty secrets about its air – four situations where our current way of life is putting our health at risk unnecessarily. The good news is that they can all be dealt with using a little science and a little will.
I recently blogged about how even a few winter wood heaters blanket whole neighbourhoods in choking smoke right across NZ. I also blogged about how concentrating people and buildings in dense urban centres risks exposing ever more people to toxic traffic pollution.
But even more common than either of these risks arises from the way we seal ourselves in homes, workplaces and vehicles as the air gradually gets more stale, more polluted and more likely to make us ill. Poor indoor air quality might be New Zealand’s guiltiest air quality secret of all – all around us, barely noticed but very difficult to escape.
I’ve spent years measuring air quality in the homes of people worried about fumes from roads or nearby industry. In almost every case they were stunned to find out that air quality was worse inside their home than outside, and often the cause was something they hadn’t even thought about. It might be the new furniture and toys they’ve bought for the new baby seeping organic compounds into a room deliberately under-ventilated with the laudable intention of keeping baby warm. It might be a few seconds of “blowback” when they open the door to the woodburner to top it up filling the room with smoke that lingers for hours. It might be an under-ventilated kitchen or bathroom that never dries out, letting an ugly mould fester and grow just out of sight. And sometimes it is pollution from that road outside, not only penetrating into the home but also being endlessly recirculated through the home by the HRV system. 
Lots of people may have a vague sense that their office, or classroom, or other workplace gets stuffy in the afternoons, but are too busy to deal with it, or assume someone else will be on to it. Maybe they’ve raised it with management, but nothing seems to have happened. Well, a lot of people do seem to be off sick at the moment.
And if that person sat next to me on the bus morning was coughing – well it’s not an air quality problem as such, is it?
Yes it is! Just recall 2020. Although at the start of the pandemic we were all focused on masking and “the 2-metre-rule” (primarily designed to stop the transmission of viral “droplets”) gradually the message got through to most people that just sharing the same air meant a risk of getting infected. And we suddenly became very aware of what a social species we are and what that means: a deep-seated need to be with other people. And increasingly we do that indoors – where we share the air as well as the space. In any home or workplace where air quality isn’t actively managed, somewhere between 1 and 5 % of the air we inhale has been recently exhaled by someone else.
The impacts on our health during “normal” conditions are very difficult to track because the risk – being indoors – happens nearly all the time, and most often doesn’t look like a risk at all. Carefully constructed research studies have successfully extracted the impact of some specific exposures to some specific health outcomes from the noise of the multiple exposures we experience every day. But as yet we have been unable to construct a comprehensive assessment of the total impact.
During the COVID-19 pandemic, however, clearer patterns began to emerge. In NZ one study found that teachers to be the profession most likely to get infected at work. Being near lots of children was not enough – it was the exchange of breathed air between them over extended periods of time that was crucial.
As a result, there were numerous efforts to improve ventilation in indoor spaces, or otherwise reduce the risk of sharing air with the infectious, especially those unaware of their infectious status. Now that the pandemic is “over” (which it is not, it’s just the emergency phase that is over) those improvements have largely been rolled back, and we have reverted to old habits.
But the pandemic is far from over for those with long COVID. And these people are just the latest additions to a group we refer to as the vulnerable – the immunocompromised, the chronically ill, infants, pregnant mothers and their children-to-be, asthmatics, and the frail. For those of us outside of this group it is very easy to forget how numerous they are. But think of your family/whanau – it is highly likely there will be one or more vulnerable members. They may be sensitive to infection, or to particulates in the air (like smoke, dust or pollen), or to chemical gasses. Our failure to really get to grips with the widespread existence of indoor air quality problems directly impacts the lives of the vulnerable, effectively acting as a barrier to access (just like stairs for a wheelchair user), and barriers to access of buildings means barriers to access to the full range of amenities, opportunities and pleasures of the human experience.
But, like each of the air quality issues I’ve previously blogged about, the solutions are available, mostly simple, and affordable if we deliver them correctly. In the vast majority of cases, it is better ventilation, and that ranges from sophisticated systems to better window-opening habits. Other solutions, like filtration, have their place. The third and fourth major components are a trigger to action, and a feedback loop (did the action work?), which is where monitoring comes in. These are really important but relatively simple actions that I will blog about more in the near future.
The paradox for indoor air quality management is that we have enough data to know that the problem exists, but not enough to know exactly how big it is, and exactly which buildings (and which rooms) are most affected. This seems to be hindering action being taken on a large scale, partly through inhibiting the adoption of mandatory indoor air quality standards. But it needn’t. Keep following our blogs to find out how the barriers can be overcome, and we can get on with tackling our most subtle but far-reaching air quality issue right now.
Because in most cases, someone isn’t on to it. But you can be.
