SCMP: Mobile app helps Hongkongers to plan out less-polluted route

SCMP article on 26 Jan 2017: Prof Alexis Lau introduced how PRAISE-HK protects public health from air pollution
Hong Kong scientists are developing a mobile app that will provide users with personalised information to identify and map out their own routes to avoid heavily polluted areas when navigating the city.
The first-of-its-kind modelling system and app powered by “big data” will give residents the ability to predict and assess real-time air quality and related health risks down to specific locations, from individual streets to rooms in a building.
The veteran air scientist behind the project said detailed and personalised analysis to such extents would enable people to make more informed decisions about minimising their risk of exposure to harmful air pollution.
“The objective is to show people what they should be most concerned about,” said Professor Alexis Lau Kai-hon of the University of Science and Technology, project coordinator of the “Personalised Real-Time Air Quality Informatics System for Exposure-Hong Kong”.
It will be a world first. Lau said such precise information was lacking in most air quality and pollution indices around the world, including Hong Kong’s own air quality health index, which he helped develop.
Hourly measurements of key air pollutants such as particulate matter, nitrogen dioxide and ozone will be analysed and the data plugged into a system. This data and other variables are then put through models to produce both real-time and near-future emissions readings and health risks.
Funded by an HSBC charity programme at an investment understood to be in the tens of millions, the first phase of the app is expected to launch next year and will be able to forecast air quality down to the street level or specific areas up to 72 hours in advance.
Lau compared the interface to the Google Traffic feature on Google Maps, which provides real-time information on road traffic conditions.
“[The system] shows what pollutant and at what concentration you are exposed to at a certain time or place,” he said.
“People can then decide for themselves – if I’m not in a hurry do I need to take this route? Should I go shopping in the morning or in the afternoon?”
The second phase will be able to conduct exposure assessment and predict pollutant exposure at a user’s current location.
Lau said users would ultimately be able to input specific data such as the type of ventilation system of a building or whether a window is left open to find out how outdoor air quality can affect indoor conditions.
The Environmental Protection Department’s air quality index, which replaced the original air pollution index in 2014, compiles data from 16 monitoring stations based on three-hour moving averages of four key pollutants, and is pegged to the increased risk of daily hospital admissions.