Outdoor Air Quality

The Air Quality Health Index (AQHI) is a scale designed to help you understand what the quality of the air around you means to your health. It’s a tool developed by health and environmental professionals to communicate the health risk posed by air pollution. There are many different types of air pollutants from a wide range of sources. Some of these pollutants have been found to contribute to cardiovascular and respiratory disease. The pollutants are often lumped together under the term smog.

The scale is designed to help you make decisions to protect your health and the environment by:

• Limiting exposure to air pollution
• Adjusting your activity during episodes of increased air pollution and encouraging physical activity on days when the index is lower
• Reducing your personal contribution to air pollution

The AQHI provides a number from 1 to 10+ to indicate the level of health risk associated with local air quality. The higher the number, the greater the health risks and precautions should be taken. The index provides specific advice for people who are especially vulnerable to the effects of air pollution as well as the general public.

The following table provides the health messages for at-risk individuals and the general public for each of the AQHI health risk categories:
 

 
People most at-risk

Some people are at a higher risk of health problems when exposed to air pollution, including:

• seniors
• pregnant individuals
• infants and young children
• people who work outdoors
• people involved in strenuous outdoor exercise
• people with an existing illness or chronic health conditions, such as:
  • cancer
  • diabetes
  • mental illness
  • lung or heart conditions

Exposure to air pollutants

Exposure to air pollutants can cause a range of symptoms. People with lung or heart disease may experience increased frequency and/or severity of symptoms, and increased medication requirements.
People who are otherwise healthy may have the following symptoms:

• irritated eyes
• increased mucus production in the nose or throat
• coughing
• difficulty breathing especially during exercise

Some people may be unaware that they have lung or heart disease. Consult your doctor if you have any: chest pain or tightness, sweating, difficulty breathing without exertion, consistent cough or shortness of breath, fluttering in the chest or feeling lightheaded.

Air Quality Events

Ontario’s Ministry of the Environment, Conservation and Parks (MECP) and Environment and Climate Change Canada (ECCC) will jointly issue a Special Air Quality Statement (SAQS) or an Air Quality Advisory (AQA) when air quality in the area deteriorates.

Special Air Quality Statement (SAQS)

An SAQS will be issued when the Air Quality Health Index (AQHI) is forecast to reach the high-risk category (AQHI of 7 to 10). The purpose of a SAQS is to be precautionary and to be vigilant of your health. An SAQS may also be issued for areas where wildfire smoke is expected to cause worsening air quality from a few hours to a few days.

Air Quality Advisory (AQA)

The Ministry will issue an AQA when the AQHI is forecast to reach, or has already reached, the very high-risk category (AQHI of 10 and over) due to wildfire smoke.

The EOHU will amplify the messaging from partners at the provincial and federal levels when the duration of the event calls for it, but encourages the public to sign up for the Ministry of the Environment, Conservation and Parks’ subscription service to be notified of every Special Air Quality Statement or Air Quality Advisory issued. Members of the public can also keep an eye on air quality in their area by regularly consulting the Ministry of the Environment, Conservation and Parks’ Air Quality Health Index (AQHI) webpage or the AQHI page on Environment and Climate Change Canada’s website.

Measures to Take When the Air Quality Health Index (AQHI) is Forecast to Reach the High-Risk Category (SAQS is Issued)

• Check your local weather forecasts and alerts for the latest air quality conditions so you know when to take precautionary measures.
• Pay attention to any medical symptoms, especially if you or individuals in your care are taking medication or have a health condition. Take a break from outdoor activities if necessary.
• Take additional precautions if you or any individuals in your care are living with cardiovascular disease or lung diseases such as asthma and chronic obstructive pulmonary disease (COPD), as air pollution at lower levels can still trigger serious health effects.
• Children and teenagers may also be at higher risk from outdoor air pollution as they tend to be more active outdoors. Young people are also at higher risk as their lungs are still developing and they have higher rates of asthma.
• Older adults are also more affected by air pollution as they tend to have pre-existing lung and cardiovascular diseases.
• If you or people in your care plan on exercising or working outdoors when air pollution levels are high, pay close attention to the weather forecasts and AQHI levels and plan your day’s activities according to when air pollution levels will be lower.
• When possible, limit your exposure to air pollution sources such as busy roads or heavy traffic areas.
• Reduce indoor air pollution by replacing your furnace and central air system’s HEPA filters every three months and eliminating pollution sources like tobacco smoke.
• Avoid using chemicals such as cleaning products, paints, finishes, and glues that can negatively affect indoor air quality.

Measures to Take When the Air Quality Health Index (AQHI) is Forecast to Reach the Very High-Risk Category (AQA is Issued) Due to Wildfire Smoke

• Reduce exposure to wildfire smoke as much as possible.
• Keep an eye on the Air Quality Health Index (AQHI) and limit outdoor activity and strenuous physical activities if necessary. Stop activities immediately if you or individuals in your care feel unwell or have difficulty breathing.
• Stay indoors and keep windows and doors closed. Turn on the air conditioning if it is too warm. If you don’t have air conditioning and it’s too warm inside, head to a local cooling centre or cleaner air space.
• Use the best quality air filter that your Heating, Ventilation, and Cooling (HVAC) system can handle. Run the system in fan mode and set it to recirculate.
• Use a portable air purifier to filter particles from wildfire smoke. Check out Health Canada’s factsheet for more information on selecting an air purifier that will best meet your needs.
• Reduce sources of indoor air pollutants and prevent wildfire smoke from infiltrating your indoor air.
• Take precautions if you need to work outdoors.
• Look for supports offered in your community during a wildfire event, such as local cooling centres or cleaner air spaces. Community centres, libraries and shopping malls could also provide some relief from wildfire smoke.
• Pay special attention to your mental health, and that of those in your care. Anyone dealing with symptoms of stress, anxiety and depression during a wildfire smoke event should consult a health professional. The resources below are offered free of charge to anyone who needs support:
  • Health 811
  • Mental Health Support
  • Kids Help Phone
  • Hope for Wellness Helpline for Indigenous peoples
• If you must spend time outdoors when an AQA is issued, a well-fitted respirator mask such as an N95 or equivalent respirator can help reduce your exposure to the fine particles in wildfire smoke, which pose the greatest risk to health. Respirator masks, however, will not protect you from the gases in wildfire smoke. If you begin to experience symptoms, it is important to listen to your body and to reduce or stop outdoor activities altogether. If possible, move to an area with cleaner air before removing your respirator. And keep in mind that respirators should not be used by:
  • children under 2 years of age
  • individuals who have trouble breathing while wearing the respirator
  • individuals who have difficulty removing the respirator

For more information on the impact of wildfire smoke on air quality, visit Health Canada’s Wildfire smoke, air quality and your health webpage.

Outdoor events

Organizers of outdoor activities and sporting events should consider:

• Consulting the AQHI before and during an event, as AQHI levels may change quickly.
• Reducing the intensity of the activity or rescheduling the event when the health risk is moderate (between 4 and 6 on the AQHI), especially if participants start experiencing symptoms.
• Rescheduling the event when the health risk is high (7 or more on the AQHI).