Residents in the area should take precautions to avoid unnecessary exposure to smoke.
DARBY TWP., Pa. (WPVI) -- Plumes of heavy smoke rose over Delaware County on Wednesday as firefighters battled a blaze at a scrap metal recycling facility, prompting air quality concerns across parts of the region.
The fire broke out just before 10 a.m. at EMR Metal Recycling on Industrial Drive in Darby Township, drawing crews from more than a dozen fire departments.

Residents reported a strong odor throughout the area as thick smoke billowed from piles of recyclable materials.
"It smelled like burnt plastic, and it's really concerning because those particles, us breathing it in, that's dangerous," said Crystal Walker of Philadelphia's Eastwick neighborhood.
The piles of debris and refuse were too difficult to navigate for firefighters pulling water hoses on the ground. As a result, crews relied heavily on ladder trucks and other aerial equipment to pour water onto the burning materials.
EMR Recycling revealed in a statement, "The fire that ignited this morning is believed to have originated at the top of a pile of inbound materials exposed to the extreme heat affecting the Philadelphia region today. "

The facility recycles metals, such as AC radiators, car batteries, aluminum, brass and copper.
The response effort unfolded in temperatures approaching 95 degrees. Officials said two first responders were hospitalized with heat exhaustion, while other crews rotated frequently to stay hydrated and cool.
It took just over four hours to fully extinguish the fire at EMR Metal Recycling, a company that has been plagued by issues.
Officials said air quality has returned to acceptable levels.
"Residents can safely resume normal activities at this time. However, sometimes air quality incidents can have health effects even after the air quality returns to normal, so if you experience symptoms including trouble breathing, heart palpitations, nausea, or dizziness, seek immediate medical attention," the Philadelphia Health Department said in a statement Wednesday night.
The air quality concerns come as the Northeast is already expecting millions to be exposed to dangerous smoke amid several large wildfires blazing in Canada and Minnesota.

The Pennsylvania Department of Environmental Protection has declared a statewide Code Red Air Quality Action Day for Thursday because of wildfire smoke from Canada and Minnesota that is expected to spread into the state. It has already created hazy conditions across parts of New England and New York.
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EMR is the same company that is currently under scrutiny for fires at their Camden facility, just over the Delaware River in New Jersey.
The Camden location has had 12 fires in the last five years, and has cited lithium-ion batteries as being an issue, and has described improper disposal of such batteries as a broader crisis. However, it is not clear if that is what caused Wednesday's fire in Darby Township.
Just last week, lawmakers signed into law that there needs to be stricter regulations and safety measures when it comes to putting out the fires in Camden.
This comes after EMR's license was temporarily suspended after a two-alarm fire on May 29.
The company recently installed a new fire suppression system at the Camden location, but officials said one unit malfunctioned during the May incident.
They were then allowed to resume operations on July 13 after making some changes to their fire response.