A giant fireball is visible as a wildfire rips through the forest by Highway 63, 16 kilometres south of Fort McMurray, Alta on Saturday, May 7, 2016. Alberta Premier Rachel Notley says the air quality in Fort McMurray almost two weeks after a vicious wildfire hit the city is a significant issue.

Image Credit: THE CANADIAN PRESS/Jonathan Hayward

EDMONTON - Alberta Premier Rachel Notley says the air quality in sooty, hazy, fire-damaged Fort McMurray is at dangerous levels, and is hampering efforts to get residents back to their homes.

The air quality heath index — a measure of smoke, ozone, and nitrogen dioxide — is so saturated with contaminants that it is off the charts, Notley told a news conference in Edmonton.

Notley said the scale is normally one to 10, with 10 being the worst, but the reading on Monday morning was at 38.

"Alberta Health Services has recommended that members of the public who had been previously arranging to return to the area under various requests not return until those conditions improve," Notley said.

"The re-entry of additional response personnel has been delayed, as has the (abandoned) vehicle retrieval efforts.

"This is something that could potentially delay recovery work and a return to the community."

Karen Grimsrud, Alberta's chief medical officer of health, said they expect the air quality readings to remain in the extreme range for the next couple of days.

She said workers in the area should be wearing respirators.

The entire population of Fort McMurray, more than 80,000 residents, are now entering their third week away from home.

Wildfires threatening the western and southern edges of the city broke through on the afternoon of May 3, destroying entire neighbourhoods and sending residents fleeing to safety.

About 2,400 structures were destroyed, but essential infrastructure, including the hospital, water treatment plant and the airport, remain intact.

Fire officials say the blaze, now at 2,850 square kilometres, remains out of control and a threat as crews deal with hotspots.

Notley said the work of making the city ready for residents continues faster than expected, and said she hopes to have timelines on the return by the end of the week.

Electricity has been restored to most of the city and municipal buildings in nearby Anzac, she said.

Gas service has been restored to about half the city, but Notley said this is a long, labour-intensive process given that lines to damaged homes must be sealed off.

The airport is ready for commercial traffic when the word is given for residents' return.

Schools are intact but Notley said regardless of when residents return they will not reopen until the new school year begins in September.

The health system remains in flux.

An urgent care centre is now operating in tents in a parking lot southeast of the hospital, providing diagnostics such as X-rays.

"Think of it like a high-tech MASH unit," said Notley.

The hospital, the Northern Lights Regional Health Centre, will be reopened in stages, starting with the emergency department by the end of the month.

Notley said staffers are working around the clock, cleaning medical equipment and ductwork hit by high levels of smoke.

The province has ordered up 32 kilometres of fencing in 100 truckloads to secure damaged and unsafe areas.

The fencing will be up this week.

Evacuees are staying in hotels, campgrounds, with friends or in reception centres south of Fort McMurray.

To help them, the province has distributed close to 28,000 pre-loaded debit cards at a cost of more than $60 million.

News from © The Canadian Press , 2016