A day after five people died of suspected carbon monoxide poisoning in Oxon Hill, firefighters are canvassing the neighborhood to check for working smoke alarms and answer questions about the deadly gas.
Fire Chief Marc Bashoor joined firefighters going door-to-door in the Southlawn community of Oxon Hill.
Firefighters also knocked on doors elsewhere in the county.
The department strongly recommends that residents install CO detectors in their home. There is no other way to detect the presence of the odorless, colorless gas.
Five adults inside an Oxon Hill home died due to carbon monoxide poisoning Tuesday, fire officials confirm to ABC 7 News.
Prince George's Fire spokesman Mark Brady says that the five people died inside a home in the 700 block of Shelby Drive in Oxon Hill.
The home owners, 56-year-old Oscar Chavez died along with his wife, 44-year-old Sonia. Sonia's sister, Nora Leiba, and two men who rented rooms in the house Nelson Landaverde and Javier Segovia, also perished.
All of these homes in the area are old, and so are many of their heating and air conditioning systems. Rheames Wooten has lived in his house since 1971. He's just across the street from where the tragedy occurred Tuesday. He says he became close to the victims, especially the homeowners Oscar and Sonia Chavez.
Authorities say an investigation is underway and autopsies are needed to confirm cause of death but it appears a detached and rusted out furnace exhaust system is to blame.
The home is in a residential area just east of Indian Head Highway, near the Capital Beltway. The victims are unrelated but attend the same church, officials say.
Authorities say carbon monoxide levels inside the home found were over 500 parts per million, a highly dangerous and likely lethal level of the colorless, odorless gas.
From the U.S. Consumer Product Safety Commission: "CO concentration is measured in parts per million (ppm). Most people will not experience any symptoms from prolonged exposure to CO levels of approximately 1 to 70 ppm but some heart patients might experience an increase in chest pain.
"As CO levels increase and remain above 70 ppm, symptoms become more noticeable and can include headache, fatigue and nausea. At sustained CO concentrations above 150 to 200 ppm, disorientation, unconsciousness, and death are possible."
At least some of the five were originally from El Salvador. Members of the victims' close-knit Spanish-speaking church hugged each other and Chavez's son as they stood behind yellow police tape.
One woman, who would not give her name, said she took comfort that the victims were with God.
Homicide detectives went to the scene, but there was no indication of foul play, said Cpl. Mike Rodriguez, a county police spokesman.
Ramon Nunoz, who lives across the street, said the married couple was originally from El Salvador and the man worked in construction.
"They were good people. I'm very sad that this happened," Nunoz said.
Fire officials could not find any carbon monoxide detector, a device that could have served as an early warning.
The Associated Press contributed to this story.
Here are safety tips from the U.S. Consumer Product Safety Commission to help prevent carbon monoxide poisoning.
* Make sure appliances are installed and operated according to the manufacturer's instructions and local building codes. Most appliances should be installed by qualified professionals. Have the heating system professionally inspected and serviced annually to ensure proper operation. The inspector should also check chimneys and flues for blockages, corrosion, partial and complete disconnections, and loose connections.
* Never service fuel-burning appliances without proper knowledge, skill and tools. Always refer to the owners manual when performing minor adjustments or servicing fuel-burning equipment.
* Never operate a portable generator or any other gasoline engine-powered tool either in or near an enclosed space such as a garage, house, or other building. Even with open doors and windows, these spaces can trap CO and allow it to quickly build to lethal levels.
* Install a CO alarm that meets the requirements of the current UL 2034 safety standard. A CO alarm can provide some added protection, but it is no substitute for proper use and upkeep of appliances that can produce CO. Install a CO alarm in the hallway near every separate sleeping area of the home. Make sure the alarm cannot be covered up by furniture or draperies.
* Never use portable fuel-burning camping equipment inside a home, garage, vehicle or tent unless it is specifically designed for use in an enclosed space and provides instructions for safe use in an enclosed area.
* Never burn charcoal inside a home, garage, vehicle, or tent.
* Never leave a car running in an attached garage, even with the garage door open.
* Never use gas appliances such as ranges, ovens, or clothes dryers to heat your home.
* Never operate unvented fuel-burning appliances in any room where people are sleeping.
* Do not cover the bottom of natural gas or propane ovens with aluminum foil. Doing so blocks the combustion air flow through the appliance and can produce CO.
* During home renovations, ensure that appliance vents and chimneys are not blocked by tarps or debris. Make sure appliances are in proper working order when renovations are complete.