The North Charleston Fire Department has been cited for two violations of workplace safety rules in the handling of a July house fire that left three firefighters injured.

Mayor Keith Summey's office on Wednesday released a copy of a report issued Sept. 9 by the state Occupational Safety and Health Administration.

The report cites the Fire Department for two serious violations of safety rules. The proposed penalty for each violation is $1,000.

The first citation is for the lack of an accountability system for tracking the movements and assignments of firefighters battling the blaze. The citation said the department "knew or should have known" that firefighters "were exposed to the hazards of being trapped in a burning residential building" and that one accepted way to deal with those hazards is to "establish and ensure the use of an initial personnel accountability system."

The second citation is for failing to adhere to the so-called "two in, two out" rule throughout the fire. The rule requires that at least two firefighters enter a burning building and remain in contact with each other, while at least two more firefighters remain outside, ready to help should an emergency arise.

On July 7, three firefighters required medical treatment after fighting a fast-moving fire that destroyed a two-story home on Purity Drive in the Hollow Oaks neighborhood. Neighbors reported hearing what sounded like a small explosion, followed by a second-story window being kicked or blown out. Photographs show two firefighters scrambling from a second-story window as smoke billows out.

Firefighter John Bolton required treatment at an Augusta burn center. He returned to light duty several weeks after the fire. Also injured were Capt. William Odum and Firefighter Antwon Green. Both have returned to full duty.

The department has 20 days to contest the OSHA citations.

Attempts to reach Fire Chief Greg Bulanow on Wednesday night were unsuccessful.

In a statement accompanying the OSHA report, Ryan Johnson of the mayor's office said the city and the Fire Department are still investigating the incident and will determine if the citations will be appealed after the investigation has concluded.