Americans in parts of Arizona and Colorado are being urged to stay indoors as blowing dust and wildfire smoke combine to create hazardous breathing conditions.Emergency air quality advisories are in effect across Arizona and Colorado. (Representative image/ Getty Images via AFP)Why have air quality alerts been issued?Emergency air quality advisories have been issued in Arizona and Colorado, with hazardous breathing conditions expected to last through Saturday.Authorities are advising residents to limit time outdoors, avoid strenuous physical activity and keep windows closed where possible until conditions improve. The advisories remain in effect through Friday evening in parts of Arizona and until Saturday morning in portions of Colorado.The warnings are especially urgent for older adults, young children and anyone with asthma, heart disease or other respiratory conditions, who face the greatest risk of serious health effects, as per Daily Mail.In Arizona, the state's Department of Environmental Quality warned that PM-10, or coarse particulate matter could reach unhealthy levels as strong winds blow dust into the air. According to the Daily Mail, these particles can enter the lungs and worsen heart and lung disease, especially in vulnerable groups.In Colorado, several counties are under Air Quality Health Advisories because wildfire smoke from active fires in Colorado and neighboring Utah is affecting the air. The report said wildfire smoke contains harmful gases, toxic organic compounds and fine particles known as PM2.5, which can travel deep into the lungs and enter the bloodstream, causing serious heart and breathing problems.Officials said the poor air quality is being caused by strong winds raising dust in Arizona while wildfire smoke continues to cover large parts of Colorado.Also Read: What caused Spain's deadly wildfire? Experts explain the blaze that killed 12Which areas are affected?The following areas are under air quality advisories:ArizonaPM-10 High Pollution Advisories have been issued for the Phoenix metropolitan area, Pinal County and Yuma where strong winds are expected to create widespread blowing dust.The advisory for Maricopa County (Phoenix metro area) remains in effect through Friday.Advisories for Pinal County continue through Saturday, while the Yuma advisory remains in effect through Friday evening.ColoradoAir Quality Health Advisories are in effect for Montrose, Ouray, San Miguel, Dolores, San Juan and Hinsdale counties where moderate to heavy wildfire smoke is expected through at least Saturday morning.A separate advisory has also been issued for Pueblo and Custer counties, where smoke from the Aspen Acres wildfire is expected to continue affecting air quality.Officials are asking residents to combine trips when possible, slow down or avoid driving on dirt roads, keep loose soil around homes and businesses under control, reduce or avoid using fireplaces and avoid using gas-powered lawn equipment.Also Read: Is Netflix buying Letterboxd? Sony and Paramount also eyeing $250M deal: ReportsWhat should residents do to stay safe?Colorado health officials said that if smoke gets thick in neighborhoods, residents should stay indoors, especially those with heart disease, respiratory illness, older adults and young children.People are also advised to limit outdoor activity when smoke is moderate to heavy, and to consider relocating temporarily if smoke enters their homes and causes illness.Officials said one warning sign is visibility, if it drops below five miles due to smoke, pollution has likely reached unhealthy levels, as per Daily Mail.