Niwa device keeps tabs on indoor pollution
WEATHER, SCIENCE AND ENVIRONMENT REPORTER
Your home may contain 20 times as many pollutants as the air outside. The problem is that it's hard to get an accurate picture of how much damage all that burnt toast, woodsmoke, pet hair, paint, and mould is doing.
That's where Pacman comes in - not the classic 1980s video game, but a Particles, Activity and Context Monitoring Autonomous Node.
It's a small device, about 10cm by 10cm, that can sit discreetly in the home monitoring all the pollutant activity as the inhabitants go about their daily lives.
It has been created by the urban air quality and health unit of the National Institute of Water and Atmospheric Research. It has open-sourced the online blueprints in an effort to get people around the world to build their their own monitors while encouraging feedback and tweaking.
The instruments in the Pacman device continuously monitor air particles, carbon dioxide, temperature and movement, and can run for a year unattended. They also feature motion and distance sensors to pinpoint the human pursuits that shape indoor air quality.
Understanding air pollution in the home is tricky because everyone uses their home in a unique way, unit manager and air quality expert Guy Coulson says.
'People are living in different atmospheres that they are creating, and breathing in different mixtures of particles.
"Working out how those mixtures are created and how they interact with each other, and with the surfaces in your home, will eventually lead to healthier homes."
Touted as having the potential to be the "biggest indoor air quality experiment ever" it will focus on particles that get deep into the lungs.
Initial findings show some activities, especially cooking and using wood-burning stoves for heating, can lead to very high levels of indoor pollutants.
"The highest measured concentrations have come from the poor use of wood-burning stoves or solid wood-burners,' Dr Coulson says.
'We want to know if exposure to short-lived, high levels of pollution are bad for you. Can one five minute exposure to very high levels of pollution have an impact on health?'
In New Zealand, poor air quality is thought to cause 730 premature deaths and cost more than $1b in restricted activity days per year.
So far, the bulk of health research into air quality has been outdoors, on large urban populations, a "statistical approach that gives a very generalised result", Dr Coulson says.
"What we don't know is how that affects us individually. We don't all live where the average value is - we move around constantly in this field and in new jobs and different houses.
'Exposure to pollutants can be much higher indoors than outdoors. We spend about 80 per cent of our time indoors, so we need to know more about indoor air quality.'
Pacman is expected to help scientists understand how many small airborne particles are in Kiwi homes, where they come from, and what activities control their fate.
On top of indoor sources, outdoor pollution penetrates most homes, even when doors and windows are shut. The project will also look to separate and identify the origins of indoor air pollution from both exterior and interior sources
'We aim to be able to tell whether the pollution comes from inside or outside the house, and to see if neighbours' wood-burners are influencing your indoor air quality as well.'
Further work is required for the scientists to be able to use and interpret the data from Pacman so that sources of indoor pollutants can be identified.
The team has already built 12 of the monitors, two of which have been stationed in Auckland volunteers' houses.
And "just to see what happens", one of the devices is also on its way to Ulan Bator in Mongolia from London, inside a very small car with Wellington Niwa scientist Aimee Whitcroft, who is competing in the Mongol Rally.
Preliminary findings from the Pacman project are expected at the end of winter.
Niwa has contacted the Japanese owners of the Pac-Man game to ask if using the acronym is OK. There has been no response, so Niwa is assuming it has their blessing.
To build your own device, go to https://bitbucket.org/guolivar/pacman
- © Fairfax NZ News
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