Heat and stagnant air is reducing air quality in Edmonton.
Alberta Health Services issued an air quality advisory Friday warning that children, the elderly, and people with respiratory or heart problems may experience breathing problems.
Even healthy adults are at risk if they are exercising or working outdoors for long periods of time, said Dr. Marcia Johnson, acting medical officer of health.
"The quality of air at present is not a health hazard for those in good health. However, people with asthma, bronchitis or emphysema should monitor their reactions and take any preventative measures their physicians have previously recommended," Johnson said in a statement.
"People who experience difficulty breathing should consult their physicians."
Johnson recommended people with respiratory conditions remain indoors with their windows closed and limit outdoor physical activity.