Neighbors reported that smoke was coming from the back of a home in the 3500 block of Sylvan Lane around 11:30 a.m. Sunday, the department said.
The Cape Cod-style home was located on a one-lane road and conditions were snowy, so "access was challenging," the fire department reported, noting that crews had to walk three-quarters of a mile to get to the scene.
Firefighters said they found heavy fire on the first and second floors, and quickly located a resident who was unconscious in the stairwell, the report stated.
First responders provided aggressive medical care to the resident, who was stabilized and taken by ambulance to the R. Adams Cowley Shock Trauma Center with critical injuries, Howard County Department of Fire & Rescue Services spokesman Marc Fischer said.
Two other individuals were able to get out of the house without firefighter assistance, according to Fischer. A second family member was taken to a local hospital
with injuries not believed to be life-threatening, and a third person was not injured, the fire department reported.
In addition to the unconscious resident, firefighters rescued two family cats, according to Fischer.
Seventy first responders including some from Baltimore County were called to the scene to assist, according to the report, which stated the fire took one hour to control and was out by 1 p.m.
Howard County highway workers helped by salting the roads around the incident, the report stated.
The cause of the fire remained under investigation Sunday, the department said.
Howard County fire officials said the house would be posted as uninhabitable Sunday due to the damage.