Spend more than 6 minutes a day in the bathroom at Chicago's WaterSaver Faucet company and you'll face disciplinary measures.

That's what a union contends the manufacturer is pulling: timing bathroom breaks and warning employees when they can't beat the clock.

The union, Teamsters local 743, filed a complaint with the National Labor Relations Board claiming WaterSaver unfairly disciplined 19 workers in June for "excessive use" of washrooms.

The company's human resources department described "excessive use of the bathroom as... 60 minutes or more over the last 10 working days," according to the affidavit. Do the math and it works out to 6 minutes a day.

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The controversy goes back to last winter when WaterSaver installed swipe card systems on bathrooms located off the factory floor.

The company said it had little choice because some employees were spending way too much time in there, and not enough time on the manufacturing line.

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WaterSaver's CEO, Steve Kersten, said 120 hours of production were lost in May because of bathroom visits outside of allotted break times.

To recoup lost hours, WaterSaver has adopted a rewards system where workers can earn a gift card of up to $20 each month ($1 a day) if they don't use the bathroom at all during work time. CEO Kersten said a few workers have already earned them.

He said that so far no one has been suspended or terminated, although warnings were issued. The company has a three step disciplinary process that starts with a verbal or written warning, which can then lead to a suspension, and finally a termination.

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The union said monitoring bathroom time is an invasion of privacy.

"The company has spreadsheets on every union employee on how long they were in the bathroom," said Nick Kreitman, the union representative at WaterSavers. "There have been meetings with workers and human resources where the workers had to explain what they were doing in the bathroom," he said.

It's unreasonable given that the human body can't always perform on cue, Kreitman said. Besides, he pointed out that the company's 140 workers don't have paid sick days. Workers who can't afford to lose a day's pay come into work sick, and may end up using bathrooms more, he said.

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Kersten said workers should be able to take care of most personal needs during the breaks the company gives them each day that total one hour. That's when workers have unlimited access to bathrooms without the electronic systems.

He said he understands people may have to use the bathroom outside of those breaks.

"No one is stopped from going to the bathroom," he said. But he believes workers might be spending time on their phones in the bathrooms.

"Our supposition is that some of the behavior is related to cell phones and texting... although I have no hard evidence," he said, pointing out that cell phones are banned on the factory floor.

Both sides gather around the bargaining table Thursday to discuss pay and paid sick days, among other things. Bathroom time will likely come up as a discussion topic.

Asked if he had to swipe into his bathroom at work, Kersten hesitated for a second and said: "No."