Along with fancy dresses, tuxedos and manicures, breathalyzers have become a mainstay at high school proms and other big dances.

The handheld device, which tests blood alcohol content by scanning a person's breath, has been used at school events for years. This Saturday will be no different, when students from both Mountain View and Los Altos high schools attend their proms.

As always, administrators will have their breathalyzers handy, randomly testing the alcohol level of students as they wait in line for the dance. Boozy breath can result in a range of punishments, up to and including suspension.

"It is wonderful. It discourages kids from partying," Los Altos Assistant Principal Cristy Dawson said of the policy. "Kids engage in risky behavior, and we don't need that at a dance."

Administrators say the policy has been around as long as they can remember, and that it has helped set a good tone for the dances. Since the breathalyzers are a well-known part of many school events, few turn up intoxicated, Dawson said.

"All the kids know we do it," she said. "You have to be a lunatic" to think you can get away with drinking.

Even so, students said, some will try.

"I know people who go drunk and figure they can get away with it," said Los Altos High School junior Siena Witte.

Punishments at each school vary for students who are caught, depending on the circumstances, including blood alcohol level. Most students are suspended, and their parents are called, but Dawson says Los Altos High does not have an exact policy for dealing with intoxication.

Prom night is one of the biggest, and last, dances of the year. This Saturday, Los Altos High students will hold their prom at the DeCathlon Club in San Jose, while Mountain View High's big event will be held aboard a San Francisco Bay cruise ship.

At Los Altos High, the principal and all three assistant principals attend prom night and help enforce the alcohol policies. For Mountain View High, normally two administrators and a law enforcement officer are present at the dances.

Students seemed to have mixed feelings about the policy.

"It's not a big deal," said Witte, as she ate lunch near the Los Altos High campus on Monday. "It hasn't affected us."

"Some of the people who drink are more worried about it," added junior Dmitry Maslenitsyn.

The schools recently received new wands that can read blood alcohol content when waved in front of a student's mouth. Still, a few students said they felt the policy was intrusive and singled out certain students.

"They say it is random, but I will definitely be breathalyzed," sophomore Alex Bailey said. "You get pulled out and everyone is looking at you."

Los Altos Principal Keith Moody said most students are compliant with the rules. "There are some kids who are the politicians and see it as a violation," he said. However, "We don't normally get a lot of resistance about things that keep students safe."

Moody added that the community has other ways to discourage drinking. Parents enforce rules at home, and leadership students help educate their peers about the dangers of alcohol and drugs.

"The parents don't condone these things," he said. "It all depends on he connectedness between school and community."

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