For much of the day Wednesday, the Canada Border Services Agency told commercial traffic to avoid the Ambassador Bridge in Windsor, Ont., due to a dispute over name tags that sparked a slowdown at North America's busiest border crossing.

The CBSA was encouraging trucks to cross into Canada at the Blue Water Bridge in Sarnia, Ont. Until early Wednesday morning, the Sarnia crossing was also affected by the job action, but the agency said work and traffic flow returned to normal before noon.

The CBSA said the disruptions were the result of refusals by several unionized officers to wear name tags — a new policy that went into effect Tuesday.

"Workers are allowed to exercise their right to refuse work that they consider dangerous," said Ron Moran, fourth vice-president of the Customs and Immigration Union.

The CBSA said border workers who took part in the job action questioned the health and safety implications of wearing a name tag.

Muhamed Bahor is a trucker who crosses the bridge on a daily basis. He said there were no delays heading into the U.S. early Wednesday.

"On the way back, it’s slow," he said.

Bahor said when he crossed back into Canada at about 11 a.m., the wait was 30 minutes.

At about the same time, the CBSA tweeted that commercial traffic delays were down to 20 minutes at the Windsor crossing and that there were no delays for travellers.

Moran said a health and safety officer was scheduled to file a report by noon. Calls CBC News made to the CBSA head office in Ottawa were not immediately returned.

In a memo to members dated Dec. 5, Customs and Immigration Union president Jean-Pierre Fortin said the union "vehemently opposes" a new name-tag policy.

He said wearing a name tag exposes members to "unnecessary risks" and he cautions members to "obey now, grieve later" to avoid any unnecessary discipline.

The agency said name tags are in line with similar policies in place in the Canadian Forces, Correctional Service of Canada and U.S. Customs and Border Protection, whose frontline uniformed officers all wear ID tags.

"It doesn’t matter if they have name tags or not. It doesn’t make a difference to me," Bahor said.

Policy 'compromises' safety of officers

Moran said the policy does nothing to improve service or the complaint process.

"It compromises the security and safety of the officers for no reason other than to project the illusion of transparency," Moran said. "Officers are already bound to provide you a badge number. The service will know immediately who you are talking about. It doesn’t change anything about the complaint process."

Moran said officers face "severe discipline" if they fail to provide a badge number.

Nathalie Des Rosiers, counsel for the Canadian Civil Liberties Association, said the name-tag policy is a good one.

"I think it’s a positive step in terms of allowing some form of accountability," she said.

Des Rosiers said the rights of CBSA employees need to be protected, too.

"It’s a question of assessment of risk. In many private enterprises you have the name of the employee as opposed to a number," she said. "I think you have to ask the question: How often are border guards the target of individualized threats?"

Des Rosiers' bigger concern is the complaint and investigation processes.

"It's nice you can identify the agent by name, but when you put your complaint forward, you are at the mercy of the internal guidelines," she said. "If you have a complaint, you must file the complaint within the department. That’s an issue we’ve been fighting for a while."

Des Rosiers wants complaints against all law enforcement agencies to be investigated by an independent third party or civilian agency.

Union seeking legal advice

Fortin writes that legal counsel is examining the name-tag requirement as the union continues to consider its options.

He also advised any member whose name is visible to the public to consider removing it in public forums such as social media and apartment building lobbies.

The CBSA said in a statement that management will closely monitor border traffic and try to resolve any unwarranted delays, adding that any illegal actions and inappropriate behaviour "will be dealt with accordingly."

The CBSA encourages travellers to consult border wait times on it website .