ALBUQUERQUE, N.M. -- The Navajo Nation Council has voted to ban smoking and chewing tobacco in public places on the vast reservation, including such outdoor venues as rodeos and fairs.

The council approved the ban on a vote of 42-27 Friday evening at the end of its weeklong summer session in the Navajo capital of Window Rock, Ariz. Navajo Nation President Joe Shirley Jr. has 10 days to decide whether to sign or veto the law once it reaches his desk.

The measure prohibits smoking and chewing tobacco in public buildings and shared public air space, but does not affect tobacco used in ceremonies for traditional or religious purposes on the reservation, an area about the size of West Virginia that encompasses parts of Arizona, New Mexico and Utah.

"I think the council made a wise decision that puts the health and well-being of the people first," the legislation's sponsor, Navajo Health and Social Services committee member Thomas Walker Jr., said Saturday.

Dr. Patricia Nez Henderson, one of those who testified for the measure, called its passage a landmark. She said it will decrease the number of young tribal members starting to smoke, help those who want to quit and protect others from secondhand smoke.

"I'm still pinching myself," said Henderson, a native of the Navajo Nation who is vice president of the Blackhill Center for American Indian Health.

Walker said the legislation stemmed from his interest in the anti-tobacco work of the Southwest Navajo Tobacco Education Prevention Project, organized by Henderson and her brother, Peter Nez. The education project, backed by the tribe's Division of Health and a group of medicine men, the Hataalii Association Inc., pushed for the ban.

Walker said Shirley made no direct commitment to sign it, but noted that about two years ago, Shirley issued his own tobacco-free proclamation and has endorsed the tobacco education group's educational efforts across the reservation.

The Division of Health would oversee compliance. Violators could be fined $100 for a first offense, $200 for a second offense and $500 for the third offense, or ordered to do increasing numbers of hours of community service.

A few other tribes have similar tobacco bans. Henderson said those include Montana's Blackfeet Nation and Fort Peck Tribe.

The Navajo Nation Gaming Enterprise opposed the measure, fearing it would put the tribe's first casino -- scheduled to open later this year on Interstate 40 near Gallup -- at a disadvantage against other Native American casinos in the area.

"All of our competitors allow smoking. If Navajo is the only facility to ban smoking, we would expect to lose at least 18 percent of our gross income," Bob Winter, the tribe's gaming czar, said last week.

Walker said that argument arose during council debate, but health concerns prevailed.

The American Cancer Society backed the measure.

Such sweeping reform strengthens and inspires people "who are trying to find their voice in the fight against big tobacco and all commercial interests who deal with tribal jurisdictions without proper regard for health and safety," said Dr. John R. Seffrin, national chief executive officer for the American Cancer Society, whose Great West Division helped fund development of the legislation and related educational outreach efforts.