A recent overdose case is highlighting the precautions Chattanooga firefighters have to take when they respond.

Hazmat crews were called to a home on Royal Fern Trail on Tuesday when first responders suspected fentanyl was present.

They are erring on the side of safety to protect themselves. Inhaling or touching a small dose of fentanyl can be deadly, which is why they're not taking any chances.

Brad Potter took a picture of his neighborhood full of first responders and a home roped off. Firefighters used hazmat suits to answer a call.

"Enter somebody's house needing medical attention and not knowing what you're dealing with and it's pretty scary," Potter said.

Officials said someone inside overdosed and died. Fentanyl was possibly the cause.

It's scenes like this that have firefighters taking more precautions when responding.

"In the past, what could be determined to be a routine call has now potentially expanded to a hazardous materials call or a life threatening call, not just for the patient, but also the people that take care of the patients," Special Operations Chief Daniel Hague of the Chattanooga Fire Department said.

Hague said procedures are constantly reviewed and updated to keep firefighters safe. He said hazmat crews have responded to a couple of fentanyl cases so far this year.

The nationwide problem has caused first responders to be more aware.

"It can affect us just like anyone else or affect law enforcement or emergency medical services," Hague said.

The Chattanooga Police Department's Violent Crimes Bureau is also investigating the case.

They said the hazmat substance has been sent off to a TBI lab to find out what it was and it doesn't appear that any first responders were exposed to it.

"It makes you wonder. It goes to show you that you don't know who is doing what anymore," Potter said.

An autopsy will give a better idea of how the person died.

Nearly two years ago, city code inspectors condemned a new home less than half a mile away on Will Kelley Road.

Police said a male nurse was found dead outside. They found evidence of fentanyl.