Environment regulators have issued a high pollution advisory and ban on wood-burning fires for Tuesday in metropolitan Phoenix.
It marks the fifth straight day that Maricopa County people have been told not to burn wood.
Open burning and use of wood burning fireplaces are generally prohibited.
People with respiratory problems are advised to avoid heavy or prolonged outdoor exertion.
"This is a big weekend for the Valley with many recreational activities," Maricopa County Air Quality Department Director Bill Wiley said. "Woodburning restrictions are in place to protect our health. Please do your part to avoid adding more pollution to our air and do not light a woodburning fire over the holiday weekend."
Tips to help make the air healthier to breathe:
Eliminate fireplace and wood stove use.
Drive as little as possible: car pool, use public transit or telecommute.
Recreational off-highway vehicle (OHV) use is prohibited during the advisory period.
The use of leaf blowers on governmental properties is prohibited during the advisory period.
Avoid using gas-powered lawn and garden equipment.
Avoid activities that generate dust, such as driving on dirt roads.
Stabilize loose soil
"The reasons for no burn days are basically to help the public protect the people who have health issues, whether it be lung issues or asthma," said Bob Huhn of the Arizona Department of Environmental Quality.
Inspectors notified of burning activity will verify the violation and send a citation by mail.
Those who burn on "no burn days" can receive fines ranging from $50 up to $250 depending on the number of wood burning violations an individual receives per year.
The Associated Press contributed to this report.