We base our recommendations on the WHO annual, daily, and hourly exposure guidelines, along with other global institutions, including the European Commission, the Chinese Air Quality Standards, and the United States EPA.
Each of the categories of the Plume AQI indicates something specific about the length of time that you can be exposed to such pollutant rates without an adverse impact on your health, so it ensures that you can get actionable information to take real steps towards improving your wellbeing.
0-20 Low Pollution
The air is clear—perfect for outdoor activities! Pollution levels are under the recommended exposure thresholds set by the World Health Organisation (WHO) for one year of pollution exposure. Nothing to worry about if your lights are green!
21-50 Moderate Pollution
Air quality is considered acceptable, though over the recommended WHO threshold for one year. This means that, unless you have these kinds of conditions all year round, you shouldn't be experiencing adverse health effects. However, there may be certain health concerns for people with specific sensitivities. Always consult your physician!
51-100 High Pollution
The air is highly polluted—above twenty-four hour exposure recommendations from the World Health Organisation. Everyone may start to feel adverse health effects, and those with sensitivities should take care when performing outdoor activities.
101+ Very High Pollution and above
Everyone may start to experience more serious health effects at these levels, and long term exposure constitutes a real health risk. Levels have exceeded the recommended WHO exposure threshold for one hour.
In certain regions, or during exceptional pollution peaks, you may experience higher levels of pollution over 200 or even 300. These warnings constitute emergency conditions. There can be harmful impacts on the general public, even in the case of short-term exposure. All individuals should avoid physical activities until pollution subsides, regardless of sensitivities.