Butler and surrounding counties were once again placed under a Code Orange Air Quality Action Day on Wednesday, July 5.

According to the Pennsylvania Department of Environmental Protection, factors such as high temperatures, light winds and lingering smoke from Canadian wildfires contribute to the Code Orange designation.

Sensitive groups are advised to limit outdoor activities during Code Orange Air Quality Action Days. Effected groups include young children, the elderly and those suffering from respiratory diseases like bronchitis or asthma.

Airnow.com also advises healthy groups to limit strenuous outdoor activity Wednesday.

Surrounding counties like Allegheny, Armstrong, Beaver, Fayette, Washington and Westmoreland were also placed in the Code Orange zone, according to the DEP.

Residents and businesses within the Air Quality Action Day areas are encouraged to voluntarily help reduce ozone air pollution by driving less, reducing vehicle trips, limiting engine idling, refueling cars and trucks after dusk, setting air conditioning to a higher temperature, and turning off lights that are not in use.