Calgarians are beginning to breathe a little easier as acrid smoke from B.C. wildfires dissipates.
But health and wildfire experts are warning the health risk level of that smoke could increase again as blazes in B.C. forests continue to rage.
"The conditions seem to be such that we'll be seeing more of this," said Dr. Jason Cabaj, medical officer of health for the Calgary Zone.
Early Monday morning, Environment Canada's air quality index in Calgary rated a 7, at the bottom of the high risk level.
By mid-afternoon it had fallen to a 5 in the moderate category and was expected to fall to the low hazard level of 3 on Tuesday.
The heavier smoke, accompanied by small amounts of ash, blew into the Calgary area early Sunday evening, carried on a cold front's gusty winds.
Cabaj said it's likely patient loads at city hospitals and clinics increased due to the smoke, which most impacts those with cardio-vascular and respiratory problems, the youngest and oldest.
"I'd expect there'll be more calls to health link and emergency visits," he said.
He said a study on the effects of wildfire smoke that severely blanketed Calgary in August, 2015 should bear results by year's end and will likely show health impacts.
Fifty sensors set up by a Calgary tech startup monitoring the level of particulates in the air shows the amount of fine debris earlier Monday in Calgary was at least 10 times the norm.
The sensors picked up readings of 111, before they began falling back, said Coral Bliss Taylor of SensorUp.
"We normally see readings of zero to 10, so it's not good, it's the worst I've seen since last October," said Taylor, referring to when the sensors were first set up in Calgary.
"We've been receiving lots of calls from the public today."
But contrast, a typical day in smoggy Beijing rates about a 73, she said.
On Monday, city officials suspended their Park N Play program for the day, with hopes of resuming the children's park activities sessions Tuesday.
University of Alberta wildfire expert Michael Flannigan said the smoke in the Calgary are was coming from fires in both B.C.'s Kootenay National Park and those deeper in the province's interior.
"It's a kind of smoke soup," he said.
Alberta Health Service's Cabaj said Calgarians should gauge the level of eye and throat irritation when deciding what kinds of outdoor activities to pursue.
"When people are noticing irritation or other symptoms, that's when they need to be cautious," he said.
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