WINSTON-SALEM, N.C. (WGHP) — Winston-Salem officials held a news conference on Tuesday afternoon to provide an update on air quality and when they will be satisfied there is no risk of explosion at the Weaver Fertilizer Plant.

Anyone who has respiratory issues is urged to stay inside. The Forsyth County Office of Environmental Assistance and Protection (FCEAP) is asking people, especially children, to avoid outdoor activity if they can see or smell the smoke or fumes from the fire.

The FCEAP will provide updates if conditions change and until local impacts to air quality subside.

The plume of smoke is vertical, but the wind direction into Tuesday evening will blow northwest. Anyone northwest of the plant should expect to see haze in the air and smell an odor similar to spent fireworks, sulfur and ammonia. The haze is not particularly toxic but should still be avoided.

Officials are likely going to maintain the one-mile evacuation distance for 48 hours or until 7 p.m. on Wednesday.

NC Commissioner of Insurance Mike Causey said the fire is smaller now than it was at 9 a.m. on Tuesday.

Experts say we shouldn’t get too comfortable with not having an explosion for at least 36 hours or 7 a.m. on Wednesday. That’s an estimation and not something completely certain, according to Causey.

Forsyth County Emergency Services Director August Vernon said it might be a week or ten days before crews can enter the plant.

“Ammonium nitrate is somewhat unpredictable — it has a history of kind of initiating a runaway exothermic reaction. We are not out of the woods. The fire is behaving as we would like for it to, but we cannot write off the chance that there’s a collapse in the pile, it gets a fresh breath of air, and we have flaming combustion on the scale that we did last night,” Vernon said.

Winston-Salem Fire Chief Trey Mayo said fire officials currently do not know the rate of consumption, and they need the fire to burn out of fuel. There are 500 tons of product on-site.

Three Winston-Salem Fire Department teams are in the area and ready to respond in the case of an emergency.

Officials with the Environmental Protection Agency are on-site and will be broadcasting air quality data back to the command post. They will then release a hazmat team from Greensboro.