DENVER - Air Care Colorado said it expects Friday to be the busiest day of the year.
"Stations are expected to be very busy," officials wrote on the Air Care Colorado website. "If possible, consider testing later in the month."
Officials said if you want to avoid the lines, test during the middle two weeks of the month or on Saturdays, arrive at the testing station before 9 a.m. and avoid any day after a holiday.
"Test volume increases every summer," said Brian Marsh, Envirotest General Manager.