New York ? At Wal-Mart these days, snowy weather is no longer an excuse for lateness. It had better be a natural disaster like a hurricane or blizzard. And being 10 minutes or more tardy for work three times will earn you a demerit. Too many of those could get you fired.

It’s all part of a revised attendance policy implemented earlier this fall that makes Wal-Mart Stores Inc. hourly workers more accountable for excessive unexcused absences and formalizes such penalties.

The new rules already are drawing fire from critics who claim they are the latest attempt by the nation’s largest private employer to weed out unhealthy and costly long-term workers as it seeks to cut labor costs.

John Simley, spokesman for Wal-Mart, calls the charges by labor-backed groups “invalid” and said the changes are an enhancement of the company’s prior policy.

“We are formalizing and enforcing the policy to ensure greater consistency and to minimize subjectivity,” he said.

Documents furnished to The Associated Press by union-backed Wake Up Wal-Mart show that employees must call an 800 number to report all absences and tardiness by an hour before the scheduled start time. They also have to call their manager with the confirmation code they received when calling the hot line number. In the past, employees got permission directly from their store managers.

“After a year of adopting antifamily policy after antifamily policy, Wal-Mart adds further insult to injury by adopting a new restrictive attendance policy that treats hard-working associates like children while penalizing them if, God forbid, they face a child or friend with a medical emergency,” said Chris Kofinis, a spokesman at union-backed Wake Up Wal-Mart.