The sky above Langley was covered with a yellow-grey cloud of smoke starting Sunday night, as wildfires burning across B.C. blotted out the sun.
Metro Vancouver issued an Air Quality Advisory for the region because of high concentrations of fine particulate matter, starting Sunday.
On Monday, the smoke left the sun as a yellowish-orange ball in the sky for much of the day, and local air quality was well outside normal levels.
Metro Vancouver warned that people with chronic underlying medical conditions should postpone strenuous exercise until the advisory is lifted.
Staying indoors in air conditioned spaces helps to reduce exposure.
Fraser Health recommends seeking medical attention if, over the next 24-36 hours, you experience difficulty breathing or wheezing.
People most at risk are those with heart or lung conditions, the elderly, and infants.
â€œWe have seen an increase in respiratory issues coming into emergency departments across the region,â€ said Tasleem Juma, a Fraser Health spokesperson.
However, it canâ€™t be said definitively if thatâ€™s linked to the smoke hanging in the air, Juma said.
According to airmap.ca, on Monday, fine particulate matter, known as PM 2.5, was at 68.4 micrograms per cubic meter, up from less than 10 on Sunday, July 5.
However, levels dropped sharply by Tuesday morning, as the haze of smoke thinned out. By 9:30 a.m., the PM 2.5 reading in Langley was down to 11.7, barely above the typical levels seen over the last week.
Larger particles, PM 10, were at 75.8 micrograms Monday, up from less than 15 a day previously. They also dropped, to 24.3, by Tuesday morning.
Fine particulate matter, PM 2.5, easily penetrate indoors because of their small size, according to Metro Vancouver.
Fraser Health and Metro Vancouver both recommend staying cool and drinking lots of water, managing conditions such as asthma or chronic respiratory disease.
For those with medical conditions, staying in a cool, air-conditioned environment and reducing indoor sources of pollution such as smoking and vacuuming was recommended. Using HEPA air filters could also help.
For those without their own filters or air conditioning, going to an air conditioned building was recommended.