A strong chemical smell forced the evacuation of the Four Seasons Pool Wednesday afternoon.

The alarm was sounded after a member of the maintenance staff noted the odour, said city recreation facilities manager Andy Beesley. Twenty-one patrons and five staff members were immediately evacuated next door to the Civic Centre.

"We do this automatically in a public facility such as a swimming pool just to be conservative and cautious," Beesley said.

No one suffered any health issues or injuries after being checked out by BC Ambulance Service personnel, but Beesely said they were transported to University Hospital of Northern BC by public transit bus as an extra precaution.

The pool remained closed Wednesday night while staff investigated the cause of the smell.

Beesley said he couldn't comment on what the cause was, but that they had ruled out chlorine.

"We don't use gas chlorine anymore in the swimming pools. We use liquid chlorine and it's in sealed containers," he said, also ruling out gas. "It's quite likely some other chemical mixture that's escaped."

The pool is scheduled to open as normal this morning at 9. "We'll take our time tonight to make sure we've thoroughly investigated and we're 100 per cent confident in everybody's safety before we reopen it," Beesley said.