On the eve of Halloween, office workers have scary decisions to make — whether or not to dress up for the year's spookiest holiday.

Mark Christensen, who works as an advancement records analyst at the University of Alberta, knows firsthand how terribly wrong things can go.

Halloween costumes in his office were essentially banned a few years ago, after one of his colleagues took things a little too far with a "pretty intense" getup.

A demonic clown

"There's sort of been a kibosh on dressing up since we had someone a few years ago dress up as a demonic clown," Christensen said in an impromptu interview with CBC Radio's Edmonton AM.

"The costume just really scared some people, and [the employee] were forced to go home and change.

"Things then had to be approved, there got to be a lot of red tape and it was more hassle than it was worth."

Tread lightly before putting on your witch mask or Justin Trudeau wig, advises Margot Ross-Graham, a workplace consultant and founder of Sandbar Coaching and Consulting.

She said it all comes down to context.

Common sense costumes

"As I've said before, common sense usually trumps common practice," Ross-Graham said in an interview Tuesday.

If you're unsure, ask a manager if other people will be dressing up for the day.

She used an infamous anecdote from CBC Edmonton as a cautionary tale, referring to the Halloween 2016 when videojournalist Travis McEwan, decked out in his fuzzy red Elmo suit, was the only person in the entire newsroom to dress up.

Video journalist Travis McEwan was a little disappointed to find he was the only one in the CBC Edmonton newsroom who showed up in costume on Halloween. 0:17

If your office is having a Halloween-themed day, go for it, Ross-Graham said. But that doesn't mean you can wear any old costume.

Anything too revealing, politically incorrect or even remotely offensive should never be seen in the office.

"Think about, 'Is what I'm wearing today going to be offensive to somebody?' " she said.

"There are thousands of costumes that you could wear. It wouldn't be hard to pick one that's appropriate."

Seriously consider the repercussions of a certain costume, she said. People who deal with customers and clients should be especially careful about going overboard. Workers hidden away in a back cubicle can likely get away with a little bit more.

Ross-Graham won't be dressing up at the office. She doesn't really enjoy the costume kitsch.

"I met my husband at a Halloween party, so it's strange that I don't like dressing up," she said. "But I do have a fondness for Halloween.

"I was a green bean, a very attractive green bean, and he was a caveman. That is the story of how we met and it's amazing that we've lasted 28 years."